Federal Register Vol. 82, No.181,

Under standard practice, the effective date of final special conditions would be 30 days after the date of publication in the Federal Register. However, as the certification date for the SAE, Silvercrest-2 SC-2D engine model is imminent; the FAA finds that good cause exists to make these special conditions effective upon publication.

On April 19, 2011, SNECMA, now known as SAE, applied for a type certificate for the Silvercrest-2 SC-2D engine model. On April 30, 2014, SAE requested an extension to their original type certificate application, which the FAA granted through June 30, 2015. On May 26, 2015, SAE requested another extension to their type certificate application, which the FAA granted through September 30, 2018.

SAE proposed an additional takeoff rating that maintains takeoff thrust in certain high ambient temperature conditions with all engines operating (AEO) for the Silvercrest-2 SC-2D engine model. Therefore, the Silvercrest-2 SC-2D engine model would have two different takeoff ratings. The first rating corresponds with the rated takeoff thrust of the engine. The second rating maintains the takeoff thrust in certain high ambient temperature conditions. This additional takeoff rating is named “Rated Takeoff Thrust at High Ambient Temperature” (Rated TOTHAT). The “Rated TOTHAT” is an approved engine thrust developed under specified altitudes and temperatures within the operating limitations established for the engine during takeoff operation for a maximum usage of 20 minutes in any one flight.

Under the provisions of Title 14, Code of Federal Regulations (14 CFR) 21.17, SAE must show that the Silvercrest-2 SC-2D engine model meets the applicable provisions of 14 CFR part 33, amendments 33-1 through 33-34 in effect on the date of application. The FAA has determined that the applicable airworthiness regulations in part 33 do not contain adequate or appropriate safety standards for the Silvercrest-2 SC-2D engine model because of their novel and unusual design feature referred to as “Rated TOTHAT”. Therefore, these special conditions are prescribed under the provisions of 14 CFR 11.19 and 14 CFR 21.16, and will become part of the type certification basis for Silvercrest-2 SC-2D engine models in accordance with § 21.17(a)(2).

If the Administrator finds that the applicable airworthiness regulations do not contain adequate or appropriate safety standards for the SAE, Silvercrest-2 SC-2D engine model because of a novel or unusual design feature, special conditions are prescribed under the provisions of § 21.16.

Special conditions are initially applicable to the engine model for which they are issued. Should the type certificate for that engine model be amended later to include any other engine model(s) that incorporates the same novel or unusual design feature, the special conditions would also apply to the other engine models under § 21.101.

In addition to complying with the applicable product airworthiness regulations and special conditions, the Silvercrest-2 SC-2D engine model must comply with the fuel venting and exhaust emission requirements of 14 CFR part 34.

The Silvercrest-2 SC-2D engine model will incorporate a novel or unusual design feature, referred to as “Rated TOTHAT”. This additional takeoff rating increases the exhaust gas temperature (EGT) limit that maintains takeoff thrust in certain high ambient temperature conditions for a maximum of 20 minutes in any one flight.

The “Rated TOTHAT” is designed for use during takeoff in specified high altitudes and high ambient temperature conditions. It maintains thrust during takeoff for a maximum of 20 minutes in any one flight. These special conditions contain additional mandatory post-flight inspection and maintenance action requirements associated with any use of the “Rated TOTHAT”. These requirements add a rating definition in paragraph 1.1 below and mandate required inspections in the instructions for continued airworthiness (ICA); instructions for installing and operating the engine; engine rating and operating limitations; instrument connection; and endurance testing.

The current requirements of the endurance test under 14 CFR 33.87 represent a typical airplane flight profile and the severity of the takeoff rating. Therefore, the endurance test under § 33.87 covers normal, AEO takeoff conditions for which the engine control system limits the engine to the takeoff thrust rating. It is intended to represent the airplane flight profile during takeoff under specified ambient temperatures for a time until the mandatory inspection and maintenance actions can be performed.

These special conditions require additional test cycles that include at least a 150 hours of engine operation as specified in § 33.87(a), to demonstrate the engine is capable of performing the “Rated TOTHAT” rating during AEO conditions without disassembly or modification.

The associated engine deterioration, after use of the “Rated TOTHAT”, is not known without the intervening mandatory inspections in these special conditions. These mandatory inspections ensure the engine will continue to comply with its certification basis, which includes these special conditions, after any use of the “Rated TOTHAT”. The applicant is expected to assess the deterioration from use of the “Rated TOTHAT”. The airworthiness limitations section (ALS) must prescribe the mandatory post-flight inspections and maintenance actions associated with any use of the “Rated TOTHAT”.

These requirements maintain a level of safety equivalent to the level intended by the applicable airworthiness standards in effect on the date of application.

Notice of proposed special conditions No. 33-17-01-SC for the SAE, Silvercrest-2 SC-2D; Rated Takeoff Thrust at High Ambient Temperature engine model was published in the Federal Register on July 03, 2017 (82 FR 30800). No comments were received, and the special conditions are adopted as proposed.

As discussed above, these special conditions are applicable to the Silvercrest-2 SC-2D engine model. Should SAE apply at a later date for a change to the type certificate to include another model on the same type certificate incorporating the same novel or unusual design feature, these special conditions would apply to that model as well.

This action affects only the “Rated TOTHAT” features on Silvercrest-2 SC-2D engine models. It is not a rule of general applicability and applies only to SAE who requested FAA approval of this engine feature.

The authority citation for these special conditions is as follows:

Accordingly, pursuant to the authority delegated to me by the Administrator, the following special conditions are issued as part of the type certification basis for SAE, Silvercrest-2 SC-2D engine model.

“Rated Take-off Thrust at High Ambient Temperature” (Rated TOTHAT) means the approved engine thrust developed under specified altitudes and temperatures within the operating limitations established for the engine during takeoff operation. Use is limited to two periods, no longer than 10 minutes each under one engine inoperative (OEI) conditions or 5 minutes each under all engines operating (AEO) conditions in any one flight for a maximum accumulated usage of 20 minutes in any one flight. Each flight where the “Rated TOTHAT” is used must be followed by mandatory inspection and maintenance actions.

In addition to the airworthiness standards in 14 CFR part 33, effective February 1, 1965, which are applicable to the engine and the “Rated TOTHAT”, the following special conditions apply:

(a) Section 33.4, Instructions for Continued Airworthiness.

(1) The ALS must prescribe the mandatory post-flight inspections and maintenance actions associated with any use of the “Rated TOTHAT”.

(2) The applicant must validate the adequacy of the inspections and maintenance actions required under paragraph 2(a)(1) of these special conditions.

(3) The applicant must establish an in-service engine evaluation program to ensure the continued adequacy of the instructions for mandatory post-flight inspections and maintenance actions prescribed under paragraph 2(a)(1) of these special conditions, and of the data for thrust assurance procedures required by paragraph 2(b)(2) of these special conditions. The program must include service engine tests or equivalent service engine test experience on engines of similar design and evaluations of service usage of the “Rated TOTHAT”.

(b) Section 33.5, Instruction manual for installing and operating the engine.

(1) Installation Instructions:

(i) The applicant must identify the means, or provisions for means, provided in compliance with the requirements of paragraph 2(e) of these special conditions.

(ii) The applicant must specify that the engine thrust control system automatically resets the thrust on the operating engine to the “Rated TOTHAT” level when one engine fails during takeoff at specified altitudes and temperatures.

(iii) The applicant must specify that the “Rated TOTHAT” is available by manual crew selection at specified altitudes and temperatures in AEO conditions.

(2) Operating Instructions: The applicant must provide data on engine performance characteristics and variability to enable the airplane manufacturer to establish airplane thrust assurance procedures.

(c) Section 33.7, Engine ratings and operating limitations.

(1) “Rated TOTHAT” and the associated operating limitations are established as follows:

(i) The thrust is the same as the engine takeoff rated thrust with extended flat rating corner point.

(ii) The rotational speed limits are the same as those associated with the engine takeoff rated thrust.

(iii) The applicant must establish a gas temperature steady-state limit and, if necessary, a transient gas over temperature limit for which the duration is no longer than 30 seconds.

(iv) The use is limited to two periods of no longer than 10 minutes each under OEI conditions or 5 minutes each under AEO conditions in any one flight, for a maximum accumulated usage of 20 minutes in any one flight. Each flight where the “Rated TOTHAT” is used must be followed by mandatory inspections and maintenance actions prescribed by paragraph 2(a)(1) of these special conditions.

(2) The applicant must propose language to include in the type certificate data sheet specified in 14 CFR 21.41 for the following:

(i) “Rated TOTHAT” and associated limitations.

(ii) As required by 14 CFR 33.5(b), Operating instructions, include a note stating that “Rated Takeoff Thrust at High Ambient Temperature (Rated TOTHAT) means the approved engine thrust developed under specified altitudes and temperatures within the operating limitations established for the engine. Use is limited to two periods, no longer than 10 minutes each under OEI conditions or 5 minutes each under AEO conditions in any one flight, for a maximum accumulated usage of 20 minutes in any one flight. Each flight where the “Rated TOTHAT” is used must be followed by mandatory inspection and maintenance actions.”

(iii) As required by § 33.5(b), Operating instructions, include a note stating that “the engine thrust control system automatically resets the thrust on the operating engine to the “Rated TOTHAT” level when one engine fails during takeoff at specified altitudes and temperatures, and the “Rated TOTHAT” is available by manual selection when all engines are operational during takeoff at specified altitudes and temperatures.”

(d) Section 33.28, Engine Control Systems.

The engine must incorporate a means, or a provision for a means, for automatic availability and automatic control of the “Rated TOTHAT” under OEI conditions and must permit manual activation of the “Rated TOTHAT” under AEO conditions.

(e) Section 33.29, Instrument connection.

The engine must:

(1) Have means, or provisions for means, to alert the pilot when the “Rated TOTHAT” is in use, when the event begins and when the time interval expires.

(2) Have means, or provision for means, which cannot be reset in flight, to:

(i) Automatically record each use and duration of the “Rated TOTHAT”, and

(ii) Alert maintenance personnel that the engine has been operated at the “Rated TOTHAT” and permit retrieval of recorded data.

(3) Have means, or provision for means, to enable routine verification of the proper operation of the means in paragraph 2(e)(1) and (e)(2) of these special conditions.

(f) Section 33.85(b), Calibration tests.

The applicant must base the calibration test on the thrust check at the end of the endurance test required by § 33.87 of these special conditions.

(g) Section 33.87, Endurance test.

(1) In addition to the applicable requirements of § 33.87(a):

(i) The § 33.87 endurance test must be modified as follows:

(A) Modify the 30 minute test cycle at the rated takeoff thrust in § 33.87(b)(2)(ii) to run one minute at rated takeoff thrust, followed by five minutes at the “Rated TOTHAT”, followed by the rated takeoff thrust for the remaining twenty-four minutes.

(B) The modified 30 minute period described above in paragraph 2(g)(1)(i)(A) must be repeated ten times in cycles 16 through 25 of the § 33.87 endurance test.

(2) After completion of the tests required by § 33.87(b), as modified in paragraph 2(g)(1)(i) above, and without intervening disassembly, except as needed to replace those parts described as consumables in the ICA, the applicant must conduct the following test sequence for a total time of not less than 120 minutes:

(i) Ten minutes at “Rated TOTHAT”.

(ii) Eighty-eight minutes at rated maximum continuous thrust.

(iii) One minute at 50 percent of rated takeoff thrust.

(iv) Ten minutes at “Rated TOTHAT”.

(v) Ten minutes at rated maximum continuous thrust.

(vi) One minute at flight idle.

(3) The test sequence of §§ 33.87(b)(1) through (b)(6) of these special conditions must be run continuously. If a stop occurs during these tests, the interrupted sequence must be repeated unless the applicant shows that the severity of the test would not be reduced if the current tests were continued.

(4) Where the engine characteristics are such that acceleration to the “Rated TOTHAT” results in a transient over temperature in excess of the steady-state temperature limit identified in paragraph 2(c)(1)(iii) of these special conditions, the transient gas over temperature must be applied to each acceleration to the “Rated TOTHAT” of the test sequence in paragraph 2(g)(2) of these special conditions.

(h) Section 33.93, Teardown inspection.

The applicant must perform the teardown inspection required by § 33.93(a), after completing the endurance test prescribed by § 33.87 of these special conditions.

(i) Section 33.201, Design and test requirements for Early ETOPS eligibility.

In addition to the requirements of § 33.201(c)(1), the simulated ETOPS mission cyclic endurance test must include two cycles of 10 minute duration, each at the “Rated TOTHAT”; one before the last diversion cycle and one at the end of the ETOPS test.

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2014-25-01, Amendment 39-18042 (79 FR 73808, December 12, 2014) (“AD 2014-25-01”). AD 2014-25-01 applied to certain Bombardier, Inc., Model DHC-8-400 series airplanes. The NPRM published in the Federal Register on May 9, 2017 (82 FR 21484). The NPRM was prompted by reports of discrepancies of a certain bolt at the pivot pin link, resulting in corrosion of the bolt. The NPRM proposed to require modifying the NLG shock strut assembly. We are issuing this AD to prevent failure of the pivot pin retention bolt, which could result in a loss of directional control or loss of an NLG tire during takeoff or landing.

Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued Canadian Airworthiness Directive CF-2009-29R2, dated December 21, 2016 (referred to after this as the Mandatory Continuing Airworthiness Information, or “the MCAI”), to correct an unsafe condition for certain Bombardier, Inc., Model DHC-8-400 series airplanes. The MCAI states:

You may examine the MCAI in the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-0334.

We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the NPRM and the FAA's response to each comment.

The Air Line Pilots Association, International concurred with the intent of the NPRM.

Horizon Air asked that we revise paragraph (g) of the proposed AD to exclude the “Job Set-up” and “Close Out” sections of Bombardier Service Bulletin 84-32-145, Revision A, dated October 18, 2016. Horizon Air stated that incorporating those sections as a requirement of the AD restricts an operator's ability to perform other maintenance in conjunction with incorporation of the referenced service information.

We agree with the commenter's request for the reason provided. We have revised paragraph (g) of this AD to require accomplishment of only paragraph 3.B., “Procedure” of the Accomplishment Instructions of Bombardier Service Bulletin 84-32-145, Revision A, dated October 18, 2016.

We reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this AD with the change described previously and minor editorial changes. We have determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM.

We also determined that these changes will not increase the economic burden on any operator or increase the scope of this AD.

Bombardier, Inc., has issued Bombardier Service Bulletin 84-32-145, Revision A, dated October 18, 2016. The service information describes procedures for modifying the NLG shock strut assembly by installing a new, improved pivot pin retention mechanism and a new retention bolt. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

We estimate that this AD affects 52 airplanes of U.S. registry.

We also estimate that it takes about 2 work-hours per product to comply with the basic requirements of this AD. The average labor rate is $85 per work-hour. Required parts will cost about $0 per product. Based on these figures, we estimate the cost of this AD on U.S. operators to be $8,840, or $170 per product.

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. “Subtitle VII: Aviation Programs,” describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in “Subtitle VII, Part A, Subpart III, Section 44701: General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to transport category airplanes to the Director of the System Oversight Division.

We determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that this AD:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);

3. Will not affect intrastate aviation in Alaska; and

4. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2013-02-12, Amendment 39-17333 (78 FR 7262, February 1, 2013) (“AD 2013-02-12”). AD 2013-02-12 applied to all EADS CASA (now Airbus Defense and Space S.A.) Model CN-235, CN-235-100, CN-235-200, and CN-235-300 airplanes. The NPRM published in the Federal Register on June 16, 2017 (82 FR 27631). The NPRM was prompted by reports of incorrect electrical polarity connections on engine fire extinguishing discharge cartridges. The NPRM proposed to continue to require identifying the correct polarity of each pair of electrical connectors of the affected engine fire extinguisher cartridge, and doing a repair if necessary. The NPRM also proposed to require modifying the installation of the fire extinguisher circuit harnesses. We are issuing this AD to detect and correct incorrect polarity connections, which could prevent the actuation of the discharge cartridge in case of automatic fire detection or manual initiation during a potential engine fire, and could result in damage to the airplane and injury to passengers.

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2016-0201, dated October 11, 2016 (referred to after this as the Mandatory Continuing Airworthiness Information, or “the MCAI”), to correct an unsafe condition for all Airbus Defense and Space S.A. Model CN-235, CN-235-100, CN-235-200, and CN-235-300 airplanes. The MCAI states:

You may examine the MCAI in the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-0555.

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public.

We reviewed the available data and determined that air safety and the public interest require adopting this AD as proposed except for minor editorial changes. We have determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM.

We reviewed EADS CASA Service Bulletin SB-235-26-0005, dated July 9, 2014. This service information describes procedures for modifying the installation of the fire extinguisher circuit harnesses.

We have also reviewed Airbus Military All Operator Letter 235-020, Revision 01, dated November 12, 2013. This service information describes procedures for identifying the correct polarity of each pair of electrical connectors of the affected engine fire extinguisher cartridge, and repairing the erroneous wiring polarity if necessary.

This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

We estimate that this AD affects 12 airplanes of U.S. registry.

We estimate the following costs to comply with this AD:

We estimate the following costs to do any necessary repair that will be required based on the results of the inspection. We have no way of determining the number of aircraft that might need this repair:

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. “Subtitle VII: Aviation Programs,” describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in “Subtitle VII, Part A, Subpart III, Section 44701: General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to transport category airplanes to the Director of the System Oversight Division.

We determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that this AD:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);

3. Will not affect intrastate aviation in Alaska; and

4. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all Airbus Defense and Space S.A. Model C-212-CB, C-212-CC, C-212-CD, C-212-CE, and C-212-DF airplanes. The NPRM published in the Federal Register on June 27, 2017 (82 FR 29019) (“the NPRM”).

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, has issued EASA Airworthiness Directive 2017-0036, dated February 21, 2017 (referred to after this as the Mandatory Continuing Airworthiness Information, or “the MCAI”), to correct an unsafe condition for all Airbus Defense and Space S.A. Model C-212-CB, C-212-CC, C-212-CD, C-212-CE, and C-212-DF airplanes. The MCAI states:

You may examine the MCAI in the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-0623.

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public.

We reviewed the relevant data and determined that air safety and the public interest require adopting this AD as proposed except for minor editorial changes. We have determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM.

Airbus Defense and Space S.A. has issued EADS CASA Service Bulletin SB-212-27-0057, dated May 21, 2014. This service information describes procedures for modifying the rudder pedal adjustment system. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

We estimate that this AD affects 42 airplanes of U.S. registry.

We estimate the following costs to comply with this AD:

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. “Subtitle VII: Aviation Programs,” describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in “Subtitle VII, Part A, Subpart III, Section 44701: General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to transport category airplanes to the Director of the System Oversight Division.

We determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that this AD:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);

3. Will not affect intrastate aviation in Alaska; and

4. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2001-16-01, Amendment 39-12369 (66 FR 40874, August 6, 2001) (“AD 2001-16-01”), which applied to certain Airbus Model A330-301, -321, -322, -341, and -342 airplanes, and certain Model A340 series airplane; and AD 2014-17-06, Amendment 39-17959 (79 FR 52181, September 3, 2014) (“AD 2014-17-06”), which applied to all Airbus Model A330-200 series airplanes, Model A330-200 Freighter series airplanes, and Model A330-300 series airplanes. AD 2014-17-06 superseded AD 2011-17-08, Amendment 39-16772 (76 FR 53303, August 26, 2011). The NPRM published in the Federal Register on June 20, 2017 (82 FR 28020). The NPRM was prompted by a determination that more restrictive maintenance instructions and airworthiness limitations are necessary. The NPRM proposed to require revising the maintenance or inspection program, as applicable, to incorporate new or revised airworthiness limitation requirements; and to remove airplanes from the applicability. We are issuing this AD to detect and correct fatigue cracking, damage, and corrosion in a certain structure, which could result in reduced structural integrity of the airplane.

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, has issued EASA Airworthiness Directive 2016-0152, dated July 27, 2016 (referred to after this as the Mandatory Continuing Airworthiness Information, or “the MCAI”), to correct an unsafe condition for all Airbus Model A330-200 Freighter, -200, and -300 series airplanes; and Model A340-200, -300, -500, and -600 series airplanes. The MCAI states:

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public.

We reviewed the available data and determined that air safety and the public interest require adopting this AD as proposed except for minor editorial changes. We have determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM.

Airbus has issued the following service information, which describes airworthiness limitation requirements for damage-tolerant airworthiness limitation items. These documents are distinct since they provide different limitation requirements.

• Airbus A330 ALS Part 2, DT-ALI, Revision 01, issue 02, dated November 30, 2015.

• Airbus A330 ALS Part 2, DT-ALI, Variation 1.1, dated December 15, 2015.

• Airbus A330 ALS Part 2, DT-ALI, Variation 1.2, dated May 27, 2016.

This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

We estimate that this AD affects 101 airplanes of U.S. registry.

The actions required by AD 2014-17-06, and retained in this AD, take about 1 work-hour per product, at an average labor rate of $85 per work-hour. Required parts cost about $0 per product. Based on these figures, the estimated cost of the actions that were required by AD 2014-17-06 is $85 per product.

We also estimate that it would take about 1 work-hour per product to comply with the basic requirements of this AD. The average labor rate is $85 per work-hour. Required parts would cost about $0 per product. Based on these figures, we estimate the cost of this AD on U.S. operators to be $8,585, or $85 per product.

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. “Subtitle VII: Aviation Programs,” describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in “Subtitle VII, Part A, Subpart III, Section 44701: General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to transport category airplanes to the Director of the System Oversight Division.

We determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that this AD:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);

3. Will not affect intrastate aviation in Alaska; and

4. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

This amendment to part 95 of the Federal Aviation Regulations (14 CFR part 95) amends, suspends, or revokes IFR altitudes governing the operation of all aircraft in flight over a specified route or any portion of that route, as well as the changeover points (COPs) for Federal airways, jet routes, or direct routes as prescribed in part 95.

The specified IFR altitudes, when used in conjunction with the prescribed changeover points for those routes, ensure navigation aid coverage that is adequate for safe flight operations and free of frequency interference. The reasons and circumstances that create the need for this amendment involve matters of flight safety and operational efficiency in the National Airspace System, are related to published aeronautical charts that are essential to the user, and provide for the safe and efficient use of the navigable airspace. In addition, those various reasons or circumstances require making this amendment effective before the next scheduled charting and publication date of the flight information to assure its timely availability to the user. The effective date of this amendment reflects those considerations. In view of the close and immediate relationship between these regulatory changes and safety in air commerce, I find that notice and public procedure before adopting this amendment are impracticable and contrary to the public interest and that good cause exists for making the amendment effective in less than 30 days.

The FAA has determined that this regulation only involves an established body of technical regulations for which frequent and routine amendments are necessary to keep them operationally current. It, therefore—(1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under DOT Regulatory Policies and Procedures (44 FR 11034; February 26, 1979); and (3) does not warrant preparation of a regulatory evaluation as the anticipated impact is so minimal. For the same reason, the FAA certifies that this amendment will not have a significant economic impact on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

Accordingly, pursuant to the authority delegated to me by the Administrator, part 95 of the Federal Aviation Regulations (14 CFR part 95) is amended as follows effective at 0901 UTC, October 12, 2017.

The Census Bureau is responsible for collecting, compiling, and publishing trade statistics for the United States under the provisions of Title 13 of the United States Code (U.S.C.), Chapter 9, Section 301. The Census Bureau published a Final Rule in the Federal Register (82 FR 18383, April 19, 2017) that revised the Foreign Trade Regulations (FTR) to reflect new export reporting requirements. In the Final Rule the Census Bureau amended the appendices section. Appendices B, C, E, and F were removed and appendix D was revised and redesignated as the new appendix B. With the revisions to the appendices section, there are a few sections of the FTR that were inadvertently not updated to reflect the changes to the appendices.

To comply with the requirements of the Foreign Relations Act, Public Law 107-228, the Census Bureau is amending relevant sections of the FTR to revise or clarify export reporting requirements. Therefore, the Census Bureau is correcting 15 CFR part 30 by making the following correcting amendments:

• Revise § 30.1(c) to replace the reference to appendix D with appendix B in the definition of “Exemption legend” because appendix D is redesignated as appendix B.

• Revise § 30.1(c) to replace the reference to appendix D with appendix B in the definition of “Postdeparture filing citation” because appendix D is redesignated as appendix B.

• Revise § 30.3(e)(2)(xi) to replace “Foreign port of unloading” with “Foreign port of unlading.”

• Revise § 30.4(b)(3) to replace “Foreign port of unloading” with “Foreign port of unlading.”

• Revise § 30.4(b)(4)(ii)(A) to replace the reference to appendix D with appendix B because appendix D is redesignated as appendix B.

• Revise § 30.6(a)(18) to remove the reference to appendix B because this appendix is removed from the FTR.

• Revise § 30.7(b) to replace the reference to appendix D with appendix B because appendix D is redesignated as appendix B.

• Revise § 30.8 introductory text to replace the reference to appendix D with appendix B because appendix D is redesignated as appendix B.

• Revise § 30.8(b) to replace the reference to § 30.46 with § 30.4(c)(2) for requirements for the filing of export information by pipeline carriers.

• Revise § 30.35 to replace the reference to appendix D with appendix B because appendix D is redesignated as appendix B.

• Revise appendix B, IX to replace the reference to § 30.40(d) with § 30.40(c).

Accordingly, 15 CFR part 30 is corrected by making the following correcting amendments:

The PTFP was a competitive grant program that supports the planning and construction of public telecommunications facilities.1 The program helped public broadcasting stations, state and local governments, Indian Tribes, and nonprofit organizations to construct public television and radio stations. On November 8, 1996, NTIA issued a final rule entitled, “Public Telecommunications Facilities Program,” to carry out its statutory responsibility to administer the PTFP.2 The regulations outlined the PTFP grant application requirements, the evaluation and selection process, post-award requirements, and the completion of PTFP grant projects. Between Fiscal Years 1994 and 2010, NTIA awarded between $14 and $42 million each year in PTFP grant awards to assist radio, television, digital television including digital conversion projects, and distance learning.

For the past seven years, no funds have been available for PTFP grants. In 2010, the Department of Commerce found that the majority of PTFP grants had assisted digital television conversion projects which had concluded, and that support for public broadcasters was available from other sources.3 For these reasons, the Department of Commerce identified the PTFP as “outdated, ineffective, or duplicative.” 4 Accordingly, Congress appropriated no funds for PTFP in Fiscal Year 2011.5

In the Federal Register of July 3, 2017 (82 FR 30731), we amended the color additive regulations in § 73.530 Spirulina extract (21 CFR 73.530) to provide for the expanded safe use of spirulina extract to seasonally color the shells of hard-boiled eggs.

We gave interested persons until August 2, 2017, to file objections or requests for a hearing. We received no objections or requests for a hearing on the final rule. Therefore, we find that the effective date of the final rule that published in the Federal Register of July 3, 2017, should be confirmed.

Throughout this document “we,” “us,” and “our” refer to EPA. This section provides additional information by addressing the following:

EPA is approving elements of the 2010 NO2 NAAQS infrastructure SIP submission from the State of Iowa received on July 29, 2013, and an amended SIP submission received on March 9, 2017. Specifically, EPA is approving the following elements of section 110(a)(2): (A), (B), (C), (D)(i)(I)—significant contribution to nonattainment (prong 1), interfering with maintenance of the NAAQS (prong 2) and (D)(i)(II)—prevent of significant deterioration of air quality (prong 3), and (D)(ii), (E) through (H), and (J) through (M). EPA is not acting on the elements of section 110(a)(2)(D)(i)(II)—protection of visibility (prong 4), and 110(a)(2)(I).

A Technical Support Document (TSD) is included as part of this docket to discuss the details of this action, including analysis of how the SIP meets the applicable 110 requirements for infrastructure SIPs.

The state submission has met the public notice requirements for SIP submissions in accordance with 40 CFR 51.102. The state initiated public comment from April 6, 2013, to May 8, 2013. One comment was received and adequately addressed in the final SIP submission. The amended submission was placed on public comment January 12, 2017, to February 15, 2017. No comments were received. These submissions also satisfied the completeness criteria of 40 CFR part 51, appendix V. In addition, as explained above and in more detail in the technical support document which is part of this docket, the revisions meets the substantive SIP requirements of the CAA, including section 110 and implementing regulations.

EPA is approving elements of the July 23, 2013, (received July 29, 2013) infrastructure SIP submission from the State of Iowa, which addresses the requirements of CAA sections 110(a)(1) and (2) as applicable to the 2010 NO2 NAAQS. As stated above, EPA is approving the following elements of section 110(a)(2): (A), (B), (C), (D)(i)(I)—significant contribution to nonattainment (prong 1), interfering with maintenance of the NAAQS (prong 2) and (D)(i)(II)—prevent significant deterioration of air quality (prong 3), and (D)(ii), (E) through (H), and (J) through (M). The March 1, 2017, SIP amendment, revised 110(a)(2)(D)(i)(I). Details of the submission are addressed in the TSD, included as part of the docket, to discuss this approval action.

EPA is not taking action on section 110(a)(2)(I). Section 110(a)(2)(I) requires that in the case of a plan or plan revision for areas designated as nonattainment areas, states must meet applicable requirements of part D of the CAA, relating to SIP requirements for designated nonattainment areas. EPA does not expect infrastructure SIP submissions to address element (I). The specific SIP submissions for designated nonattainment areas, as required under CAA title I, part D, are subject to different submission schedules than those for section 110 infrastructure elements. EPA will take action on part D attainment plan SIP submissions through a separate rulemaking governed by the requirements for nonattainment areas, as described in part D.

EPA is not taking action on section 110(a)(2)(D)(i)(II), prong 4.

We are publishing this direct final rule without a prior proposed rule because we view this as a noncontroversial action and anticipate no adverse comment. However, in the “Proposed Rules” section of this Federal Register, we are publishing a separate document that will serve as the proposed rule to approve the SIP revision if adverse comments are received on this direct final rule. We will not institute a second comment period on this action. Any parties interested in commenting must do so at this time. For further information about commenting on this rule, see the ADDRESSES section of this document. If EPA receives adverse comment, we will publish a timely withdrawal in the Federal Register informing the public that this direct final rule will not take effect. We will address all public comments in any subsequent final rule based on the proposed rule.

Under the CAA, the Administrator is required to approve a SIP submission that complies with the provisions of the Act and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, EPA's role is to approve state choices, provided that they meet the criteria of the CAA. Accordingly, this action merely approves state law as meeting Federal requirements and does not impose additional requirements beyond those imposed by state law. For that reason, this action:

• Is not a significant regulatory action subject to review by the Office of Management and Budget under Executive Orders 12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011);

• Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);

• Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.);

• Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);

• Does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999);

• Is not an economically significant regulatory action based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997);

• Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001);

• Is not subject to requirements of Section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application of those requirements would be inconsistent with the CAA; and

• Does not provide EPA with the discretionary authority to address, as appropriate, disproportionate human health or environmental effects, using practicable and legally permissible methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).

The SIP is not approved to apply on any Indian reservation land or in any other area where EPA or an Indian tribe has demonstrated that a tribe has jurisdiction. In those areas of Indian country, the rule does not have tribal implications and will not impose substantial direct costs on tribal governments or preempt tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the Small Business Regulatory Enforcement Fairness Act of 1996, generally provides that before a rule may take effect, the agency promulgating the rule must submit a rule report, which includes a copy of the rule, to each House of the Congress and to the Comptroller General of the United States. EPA will submit a report containing this action and other required information to the U.S. Senate, the U.S. House of Representatives, and the Comptroller General of the United States prior to publication of the rule in the Federal Register. A major rule cannot take effect until 60 days after it is published in the Federal Register. This action is not a “major rule” as defined by 5 U.S.C. 804(2).

Under section 307(b)(1) of the CAA, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by November 20, 2017. Filing a petition for reconsideration by the Administrator of this final rule does not affect the finality of this action for the purposes of judicial review nor does it extend the time within which a petition for judicial review may be filed, and shall not postpone the effectiveness of such rule or action. This action may not be challenged later in proceedings to enforce its requirements. (See section 307(b)(2).)

For the reasons stated in the preamble, EPA amending 40 CFR part 52 as set forth below:

Throughout this document “we,” “us,” and “our” refer to EPA. This section provides additional information by addressing the following:

EPA is taking direct final action to approve the infrastructure submissions as meeting the submittal requirement section 110(a)(1). EPA is approving elements of the 2010 NO2 and SO2 infrastructure SIP submissions from the State of Nebraska received on February 7, 2013, and August 22, 2013, respectively. EPA is also taking action to approve the 2012 PM2.5 infrastructure submittal received on February 22, 2016. Specifically, EPA is approving, in regard to the 2010 NO2 NAAQS, the following elements of section 110(a)(2): (A) through (C), (D)(i)(I)—Prongs 1 and 2, (D)(i)(II)—prong 3, (D)(ii), (E) through (H), and (J) through (M).

In regard to the 2010 SO2 and 2012 PM2.5 NAAQS, EPA is approving the following infrastructure elements of 110(a)(2): (A) through (C), (D)(i)(II)—Prong 3, (D)(ii), (E) through (H), and (J) through (M). As discussed in the TSD, EPA is not acting, at this time, on section 110(a)(2)(D)(i)(I)—prongs 1 and 2, as it relates to the 2010 SO2 and 2012 PM2.5 NAAQS.

In regard to the 2010 NO2 and SO2 and the 2012 PM2.5 infrastructure submittals and as explained in the TSD, EPA is not acting, at this time, on section (D)(i)(II)—prong 4. Finally, EPA is not acting on section 110(a)(2)(I) as it does not expect infrastructure SIP submissions to address element (I).

As noted, a Technical Support Document (TSD) is included as part of the docket to discuss the details of this action.

The state submissions have met the public notification requirements for SIP submissions in accordance with 40 CFR 51.102. A public comment period was held for the NO2 infrastructure SIP from December 27, 2012 to January 28, 2013.

The only comments were from the EPA, and the infrastructure SIP submission was revised to address the comments. A public hearing was held on January 28, 2013.

The state held a public comment period for the SO2 infrastructure SIP from April 25, 2013, to May 28, 2013. NDEQ received comments from the Sierra Club on May 28, 2013. The state addressed the Sierra Clubs comments with no revisions to its proposed SIP. A public hearing was held on May 27, 2013.

A public comment period was held for the PM2.5 infrastructure SIP from November 23, 2015, to December 29, 2015. A public hearing was held on December 29, 2015. No comments were received.

All three submissions satisfied the completeness criteria of 40 CFR part 51, appendix V. As explained in more detail in the TSD, which is part of this docket, the revisions meet the substantive SIP requirements of the CAA, including section 110 and implementing regulations.

EPA is approving the infrastructure SIP submissions from Nebraska, which address the requirements of CAA sections 110(a)(1) and (2) as applicable to the 2010 NO2 and SO2 and 2012 PM2.5 NAAQS. As stated in the above preamble, EPA is approving elements of the state's submission as meeting requirements of section 110(a)(1) for all three submittals.

With regard to the 2010 NO2 NAAQS, EPA is approving the following infrastructure elements of 110(a)(2): (A) through (C), (D)(i)(I)—Prongs 1 and 2, (D)(i)(II)—prong 3, (D)(ii), (E) through (H), and (J) through (M). As explained in the TSD, EPA intends to act on section (D)(i)(II)—prong 4, in a subsequent rulemaking.

EPA is approving the following infrastructure elements of 110(a)(2) as it relates to the 2010 SO2 and the 2012 PM2.5 NAAQS: (A) through (C), (D)(i)(II)—Prong 3, (D) (ii), (E) through (H), and (J) through (M). As discussed in the TSD, EPA intends to act on section (D)(i)(II)—prong 4, in a subsequent rulemaking and is not acting, at this time, on section 110(a)(2)(D)(i)(I)—prongs 1 and 2, for both the 2010 SO2 and 2012 PM2.5 NAAQS.

Finally, EPA is taking no action with respect to section 110(a)(2)(I) for the 2010 NO2 and SO2 NAAQS, and the 2012 PM2.5 NAAQS. Section 110(a)(2)(I) requires that in the case of a plan or plan revision for areas designated as nonattainment areas, states must meet applicable requirements of part D of the CAA, relating to SIP requirements for designated nonattainment areas. EPA does not expect infrastructure SIP submissions to address element (I). The specific SIP submissions for designated nonattainment areas, as required under CAA title I, part D, are subject to different submission schedules than those for section 110 infrastructure elements. EPA takes action on part D attainment plan SIP submissions through separate rulemaking governed by the requirements for nonattainment areas, as described in part D. EPA has not designated any area in the U.S. as nonattainment for the 2010 NO2 NAAQS; EPA has designated all areas of Nebraska as “attainment/unclassified” with regards to the 2012 PM2.5 NAAQS. Additionally, EPA has designated Lincoln and Otoe Counties as “attainment/unclassified” for the 2010 1-hr SO2 NAAQS, but has not yet made a final determination for the rest of the Nebraska as it relates to the 2010 SO2 NAAQS. Nebraska has no current CAA requirement to submit a plan to address section 110(a)(2)(I).

Based upon review of the state's infrastructure SIP submissions for the 2010 NO2 and SO2 NAAQS as well as the 2012 PM2.5 NAAQS, and relevant statutory and regulatory authorities and provisions referenced in the submissions or referenced in Nebraska's SIP, EPA believes that Nebraska has the infrastructure to address all applicable required elements of sections 110(a)(1) and (2) (except otherwise noted) to ensure that the 2010 NO2 and SO2 NAAQS and the 2012 PM2.5 NAAQS are implemented in the state.

We are publishing this direct final rule without a prior proposed rule because we view this as a noncontroversial action and anticipate no adverse comment. However, in the “Proposed Rules” section of this Federal Register, we are publishing a separate document that will serve as the proposed rule to this action partionally approving elements of section 110(a)(2) for the 2010 NO2 and SO2 NAAQS and the 2012 PM2.5 NAAQS, if adverse comments are received on this direct final rule. We will not institute a second comment period on this action. Any parties interested in commenting must do so at this time. For further information about commenting on this rule, see the ADDRESSES section of this document. If EPA receives adverse comment, we will publish a timely withdrawal in the Federal Register informing the public that this direct final rule will not take effect. We will address all public comments in any subsequent final rule based on the proposed rule.

Under the CAA, the Administrator is required to approve a SIP submission that complies with the provisions of the Act and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, EPA's role is to approve state choices, provided that they meet the criteria of the CAA. Accordingly, this action merely approves state law as meeting Federal requirements and does not impose additional requirements beyond those imposed by state law. For that reason, this action:

• Is not a significant regulatory action subject to review by the Office of Management and Budget under Executive Orders 12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011);

• Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);

• Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.);

• Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);

• Does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999);

• Is not an economically significant regulatory action based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997);

• Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001);

• Is not subject to requirements of Section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application of those requirements would be inconsistent with the CAA; and

• Does not provide EPA with the discretionary authority to address, as appropriate, disproportionate human health or environmental effects, using practicable and legally permissible methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).

The SIP is not approved to apply on any Indian reservation land or in any other area where EPA or an Indian tribe has demonstrated that a tribe has jurisdiction. In those areas of Indian country, the rule does not have tribal implications and will not impose substantial direct costs on tribal governments or preempt tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the Small Business Regulatory Enforcement Fairness Act of 1996, generally provides that before a rule may take effect, the agency promulgating the rule must submit a rule report, which includes a copy of the rule, to each House of the Congress and to the Comptroller General of the United States. EPA will submit a report containing this action and other required information to the U.S. Senate, the U.S. House of Representatives, and the Comptroller General of the United States prior to publication of the rule in the Federal Register. A major rule cannot take effect until 60 days after it is published in the Federal Register. This action is not a “major rule” as defined by 5 U.S.C. 804(2).

Under section 307(b)(1) of the CAA, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by November 20, 2017. Filing a petition for reconsideration by the Administrator of this final rule does not affect the finality of this action for the purposes of judicial review nor does it extend the time within which a petition for judicial review may be filed, and shall not postpone the effectiveness of such rule or action. This action may not be challenged later in proceedings to enforce its requirements. (See section 307(b)(2).)

For the reasons stated in the preamble, EPA amends 40 CFR part 52 as set forth below:

Throughout this document, “we,” “us” and “our” refer to the EPA.

On June 15, 2017 (82 FR 27451), under section 110(k)(3) of the Clean Air Act (CAA or “Act”), the EPA proposed to approve the “2016 AQMP Reasonably Available Control Technology (RACT) Demonstration” (“2016 AQMP RACT SIP”), submitted to the EPA by the California Air Resources Board (CARB) on July 18, 2014 1 for approval as a revision to the California SIP, as supplemented by the public draft versions of the “Supplemental RACM/RACT Analysis for the NOX RECLAIM Program” (“2017 RACT Supplement”) and two negative declarations submitted by CARB on May 22, 2017.2 We had previously proposed a partial approval and partial disapproval of the 2016 Air Quality Management Plan (AQMP) RACT SIP,3 but withdrew that proposal because we found that the 2017 RACT Supplement and recent amendments to certain District rules adequately addressed the deficiency that had been the basis for the earlier proposed partial disapproval. References herein to the “proposed rule” or “proposed action” refer to our proposed action published on June 15, 2017, unless otherwise stated.

Our proposed rule was based on our evaluation of the public draft versions of the 2017 RACT Supplement and negative declarations, and we indicated that we would not take final action until CARB submitted the final adopted versions to the EPA as a SIP revision. On July 7, 2017, the SCAQMD held a public hearing and approved the 2017 RACT Supplement and two negative declarations and submitted the approval package to CARB for adoption and submittal to the EPA. On July 26, 2017, the CARB Executive Officer adopted the 2017 RACT Supplement and negative declarations as a revision to the California SIP and, on July 27, 2017, submitted them to the EPA for approval, thereby satisfying the condition 4 for final EPA action.

The District prepared the 2017 RACT Supplement to address a deficiency that the EPA had identified in the 2016 AQMP RACT SIP and that was the basis for the EPA's proposed partial disapproval published on November 3, 2016 (81 FR 76547).5 The final versions of the 2017 RACT Supplement (which includes additional analyses and certain permit conditions for two specific stationary sources in Coachella Valley) and negative declarations include non-substantive changes from the public draft versions that were the basis for our June 15, 2017 proposed rule. Lastly, CARB's July 27, 2017 SIP revision submittal includes documentation of the public process followed by the SCAQMD to approve the 2017 RACT Supplement and related negative declarations and documentation of the adoption by CARB of the 2017 RACT Supplement and negative declarations as revisions to the California SIP.

On August 7, 2017, we found the 2017 RACT Supplement including certain conditions from permits for two specific stationary sources located in Coachella Valley, and two negative declarations met the completeness criteria in 40 CFR part 51, appendix V.6 Today, we take final action on the 2016 AQMP RACT SIP submitted on July 18, 2014 as supplemented by the 2017 RACT Supplement and negative declarations submitted on July 27, 2017.

In our proposed rule, we explained that CAA sections 182(b)(2) and (f) require that SIPs for ozone nonattainment areas classified as Moderate or above implement RACT for any source covered by a Control Techniques Guidelines 7 (CTG) document and for any major source of volatile organic compounds (VOC) or nitrogen oxides (NOX).8 The EPA's implementing regulations for the 2008 ozone NAAQS explain how these RACT requirements will be applied in areas classified as Moderate or above for the 2008 ozone NAAQS. See 40 CFR 51.1112.

We further explained that the areas under discussion here are subject to the RACT requirement as the South Coast Air Basin (“South Coast”) is classified as an Extreme nonattainment area and the Coachella Valley portion of Riverside County (“Coachella Valley”) is classified as a Severe-15 nonattainment area for the 2008 8-hour ozone NAAQS (40 CFR 81.305); 77 FR 30088 at 30101 and 30103 (May 21, 2012). SCAQMD implements the RACT requirements for South Coast and Coachella Valley because it is authorized under state law to regulate stationary sources in those areas. Therefore, the SCAQMD must, at a minimum, adopt requirements to achieve emissions reductions equivalent to RACT-level controls for all sources covered by a CTG document and for all major non-CTG sources of VOC or NOX within the two nonattainment areas. Any stationary source that emits or has the potential to emit at least 10 tons per year of VOC or NOX is a major stationary source in an extreme ozone nonattainment area (CAA section 182(e) and (f)), and any stationary source that emits or has the potential to emit at least 25 tons per year of VOC or NOX is a major stationary source in a severe ozone nonattainment area (CAA section 182(d) and (f)).

In our proposed rule, we evaluated the 2016 AQMP RACT Demonstration, 2017 RACT Supplement and negative declarations in light of the above requirements and concluded that, collectively, they meet the RACT requirements of CAA sections 182(b)(2) and (f) and 40 CFR 51.1112 for the South Coast and Coachella Valley nonattainment areas for the 2008 ozone standard. In this document, we provide a summary of our evaluation. For a more detailed discussion, please see the proposed rule at 82 FR 27451, pages 27453 through 27455.

First, based on our review of the documentation provided by the SCAQMD in the 2016 AQMP RACT SIP and the negative declarations, we agreed that existing District rules approved in the SIP meet or are more stringent than the corresponding CTG limits and applicability thresholds for each category of VOC sources covered by a CTG document or are covered by negative declarations for which we were proposing approval. In this action, we affirm the finding we made in the proposed rule with respect to the CTG portion of the RACT requirement and approve the two negative declarations as a revision to the California SIP.

Next, with respect to major stationary sources of VOC or NOX emissions, we divided the evaluation into three parts: major non-CTG VOC and NOX stationary sources that are subject to District's command-and-control VOC and NOX rules, major sources located in the South Coast that are subject to the District's cap-and-trade program referred to as the Regional Clean Air Incentives Market (“RECLAIM”) program, and major sources located in Coachella Valley that are subject to RECLAIM.

With respect to the first part of the evaluation of RACT for major sources, we reviewed the information provided by the District regarding new major Title V sources receiving permits since the District's previous RACT SIP approval and agreed with the District that the District's command-and-control VOC and NOX rules approved in the SIP require implementation of RACT for all major non-CTG VOC and NOX sources in the South Coast and Coachella Valley to which those rules apply. We affirm that finding in this final action.

In connection with the second part of the evaluation, we described RECLAIM as a program adopted by the District to reduce emissions from the largest stationary sources of NOX and sulfur oxides (SOX) emissions through a market-based trading program that establishes annual declining NOX and SOX allocations (also called “facility caps”) and allows covered facilities to comply with their facility caps by installing pollution control equipment, changing operations, or purchasing RECLAIM trading credits (RTCs) from the RECLAIM market. We noted that section 40440 of the California Health and Safety Code (CH&SC) requires the District to monitor advances in best available retrofit control technology (BARCT) and periodically to reassess the overall facility caps to ensure that the facility caps are equivalent, in the aggregate, to BARCT emission levels imposed on affected sources; 9 that facilities subject to RECLAIM are exempted from a number of District command-and-control (also referred to as “prohibitory”) rules that otherwise apply to sources of NOX and SOX emissions in the South Coast; 10 and that, with certain exceptions, facilities located outside of the South Coast but within SCAQMD jurisdiction (e.g., facilities in Coachella Valley) are not included in the RECLAIM program.

Under longstanding EPA interpretation of the CAA, a market-based cap and trade program may satisfy RACT requirements by ensuring that the level of emission reductions resulting from implementation of the program will be equal, in the aggregate, to those reductions expected from the direct application of RACT on all affected sources within the nonattainment area,11 and, consistent with our longstanding interpretation of the CAA, we approved the RECLAIM program in 1998 and then, as amended, in 2006 and 2011, based in part on the conclusion that RECLAIM continued to satisfy RACT requirements.12 More recently, in the Agency's 2008 Ozone SIP Requirements Rule, 80 FR 12264, at 12278-12283 (March 6, 2015), the EPA re-affirmed its longstanding interpretation that a market-based cap and trade program may satisfy RACT requirements by ensuring equal aggregate reductions; and in this action, we are approving SIP revisions that rely in part on such a program to meet the RACT requirement because we find the program consistent with our 2008 Ozone SIP Requirements Rule.

As noted above, state law requires the District to monitor advances in BARCT and to periodically reassess the overall facility caps to ensure that RECLAIM facilities achieve the same or greater emission reductions that would have occurred under a command-and-control approach. In 2005, the District examined the RECLAIM program, found that additional reduction opportunities existed due to the advancement of control technology, and amended the RECLAIM rules (i.e., District Regulation XX) to reduce the facility annual allocations (in the aggregate) for NOX from 34.2 tons per day (tpd) to 26.5 tpd. In 2015, the District conducted another reevaluation and amended the RECLAIM rules to further reduce the NOX allocations (in the aggregate) from 26.5 tpd to 14.5 tpd to be achieved through downward incremental adjustments from 2017 through 2022. At the time of our proposed rule, the EPA had only proposed to approve the RECLAIM rules that reflect the 2015 amendments reducing the aggregate facility allocations to 14.5 tpd of NOX, but the Agency has since taken final action, and the RECLAIM rules, as amended in 2015, are now approved into the California SIP.13

In the 2017 RACT Supplement, the District provided a demonstration of how the RECLAIM program, as amended in 2015, meets the RACT requirement in the aggregate. To do so, the District re-examined the BARCT reevaluation that it conducted in 2015 and determined that, for certain source categories, the BARCT allocation level was essentially equivalent to RACT, but that, for certain other source categories, the BARCT allocation level was beyond RACT because there were no other rules in the District itself or any other California air district for these specific categories that were more stringent than the limits established under the RECLAIM program in effect prior to the 2015 amendments. The District then re-calculated hypothetical facility annual allocations (in the aggregate) reflecting RACT implementation (rather than BARCT) of 14.8 tpd. Because the facility annual allocations (in the aggregate) for NOX adopted by the District in 2015 (implementing BARCT) of 14.5 tpd is less than (i.e., more stringent than) the hypothetical allocations (implementing RACT) of 14.8 tpd, the District concluded that the program as amended in 2015 meets the RACT requirement.

In our proposed rule, based on our review of the District's approach, assumptions, and methods to the updated RECLAIM program, we agreed that, as amended in 2015, the RECLAIM program provides for emissions reductions greater, in the aggregate, to those reductions expected from the direct application of RACT on all major NOX sources in the South Coast and thereby meets the RACT requirement for such sources for the purposes of the 2008 ozone standard.14 We affirm that finding in this final action and approve the 2016 AQMP RACT SIP, as supplemented in the 2017 RACT Supplement.

Lastly, with respect to the two major NOX sources in Coachella Valley that are not otherwise subject to District RACT-level command-and-control regulations, we proposed approval of certain permit conditions that were included in appendices A and B to the 2017 RACT Supplement. As described in the proposed rule, the permit conditions submitted by the District for these facilities (both of which are electric generating facilities) pertain to specified NOX emission limits ranging from 2.5 to 5 parts per million (ppm) for the gas turbines, control technology (selective catalytic reduction (SCR)), and monitoring, among other elements. The District's analysis indicated that SCR is generally identified as an emission control technology to achieve “best available control technology” emission limits in the range of 2 to 5 ppm for gas turbines, and thus the controls meet or exceed the requirements for RACT. We reviewed the permit conditions (and SCAQMD's analysis) and found that they provide for RACT level of control (or better) at the two subject facilities in Coachella Valley. In this action, we affirm that finding and are approving into the SIP the submitted permit conditions for the two specific major NOX sources in Coachella Valley.

For more background information and a more extensive discussion of the 2016 AQMP RACT Demonstration, the 2017 RACT Supplement, and negative declarations and our evaluation of them for compliance with CAA RACT requirements, please see our proposed rule and related technical support document (TSD).

The EPA's proposed action provided a 30-day public comment period which ended on July 17, 2017. During this period, we received comments from Earthjustice, which submitted comments on behalf of the Sierra Club.15 In the following paragraphs, we summarize the comments and provide our responses.

Comment #1: Earthjustice contends that a cap-and-trade program, such as RECLAIM, can never provide the basis for compliance with the RACT requirement in CAA sections 182(b)(2) and 182(f) based on the plain language of the CAA that, according to Earthjustice, requires all major sources to implement RACT, i.e., RACT must be met by each individual major source and cannot be met by achieving equivalent levels of emission reductions across the nonattainment area. In support of this contention, Earthjustice highlights the word “all” in CAA section 182(b)(2) in connection with implementation of RACT at major sources and cites legislative history for the CAA Amendments of 1990 that purports to emphasize the applicability of the RACT requirement to all major sources of NOX in an ozone nonattainment area.

Earthjustice also views the EPA's longstanding definition of RACT as supporting an interpretation of the RACT requirement as applicable to each and every major NOX source, not a collective emission limitation for an entire class of sources located across a nonattainment area or an entire state or region. Earthjustice also claims that reliance on emissions trading to meet the RACT requirement for major NOX sources is tantamount to creating a NOX exemption that is inconsistent with the explicit NOX exemptions found at CAA section 182(f). Lastly, Earthjustice cites the EPA's November 3, 2016 proposed rule as further support that emissions averaging in the South Coast does not actually provide RACT-level reductions.

Response #1: We disagree that a cap-and-trade program can never be approved as meeting the RACT requirement of CAA sections 182(b)(2) and 182(f). First, we note that our action today is consistent with our past approval actions on the RECLAIM rules and amendments as meeting the RACT requirement and, more recently, with our SIP requirements rule for the 2008 ozone standard (“2008 Ozone SIP Requirements Rule”) that indicates that a cap-and-trade approach remains a viable option to comply with the RACT requirement. More specifically, in our final 2008 Ozone SIP Requirements Rule, we indicated that states have the option of conducting a technical analysis for a nonattainment area considering the emissions controls required by a regional cap-and-trade program, and demonstrating that compliance by certain sources participating in the cap-and-trade program results in actual emission reductions in the particular nonattainment area that are equal to or greater than the emission reductions that would result if RACT were applied to an individual source or source category within the nonattainment area. See 80 FR 12264, at 12279 (March 6, 2015). For additional discussion of this option, please see our proposed 2008 Ozone SIP Requirements Rule at 78 FR 34178, at 34192-34193 (June 6, 2013).16

Second, CAA section 182(b)(2), in relevant part, provides that the state shall submit a revision to the SIP to include provisions to require the implementation of RACT under section 172(c)(1) of this title with respect to, among other categories, all other major stationary sources of VOC that are located in the area, and Section 182(f) extends the requirements for major stationary sources of VOC to major stationary sources of NOX, unless exempted under the terms of section 182(f). As such, CAA section 172(c)(1) is explicitly brought into section 182(b)(2) and affects how it is interpreted. Specifically, section 172(c)(1), in relevant part, requires SIP revisions for nonattainment areas to “provide for the implementation of all reasonably available control measures as expeditiously as practicable (including such reductions in emissions from existing sources in the area as may be obtained through the adoption, at a minimum, of reasonably available control technology).”

The plain language of section 172(c)(1)—“such reductions . . . as may be obtained through the adoption, at a minimum, of reasonably available control technology”—does not require reductions from each individual source but rather only requires areas to achieve the same level of emissions reductions from stationary sources that installing reasonably available control technology would yield. In other words, as long as the level of emissions reductions obtained in the area from stationary sources equals or exceeds the level of emissions reductions that would be achieved through implementation of RACT at existing sources, then the RACT requirement of section 172(c)(1) are met. See NRDC v. EPA, 571 F.3d 1245, 1256-58 (D.C. Cir. 2009).

Section 182(b)(2) simply prescribes a more specific bar for the required level of emissions reductions that must be obtained. With respect to major stationary sources of NOX, the bar for the required level of emissions reductions that must be obtained is calculated based on the emissions reductions that can be achieved through implementation of RACT at major stationary sources of NOX. Consistent with section 172(c)(1), the emissions reductions need not come from the major NOX sources themselves so long as an equal or greater level of emissions reductions are obtained within the area. As such, the plain language of sections 172(c)(1) and 182(b)(2) allows a cap-and-trade program to meet the RACT requirements of those sections for major NOX sources so long as the overall emissions reductions that are obtained equal or exceed that level of emissions reductions that would have been obtained through implementation of RACT at the major NOX sources themselves. The plain language of the CAA supporting the EPA's interpretation negates the need to consult the legislative history cited by Earthjustice in its comment.

The area-wide—rather than individual, source-specific—nature of the RACT requirement is reinforced by CAA section 182(b)(2), which requires states to revise their SIPs to adopt RACT “with respect to” specified categories of VOC sources. The plain language of that provision does not mandate emission reductions from each individual source. In contrast, the next subsection of that same provision imposes individual, source-specific requirements by mandating that State Implementation Plans “require all owners or operators of gasoline dispensing systems to install and operate . . . a system for gasoline vapor recovery. . . .” See CAA section 182(b)(3).

Third, Earthjustice cites the EPA's longstanding definition of RACT as support for its position, however, the definition cited in the comment does not require an individual, source-specific application of control technology. Instead, it is used solely as the beginning point for the extrapolation of the total reductions that each nonattainment area must achieve to satisfy the section 172(c)(1) RACT requirement.

Fourth, we also disagree with the claim that reliance on emissions trading to meet the RACT requirement for major NOX sources is tantamount to creating a NOX exemption and that such an exemption is inconsistent with the explicit NOX exemptions found at CAA section 182(f). The RECLAIM program in the South Coast provides no exemption per se for major NOX sources. Each such source must install controls or purchase credits sufficient to meet their annual allocation.

Lastly, we acknowledge Earthjustice's comment that our November 3, 2016 rulemaking proposed to partially disapprove the 2016 AQMP RACT SIP because of deficiencies in the RECLAIM rules. However, our proposed partial disapproval was not based on the fact that RECLAIM is an emissions averaging program but rather on the evidence at hand that suggested that the then-current SIP RECLAIM program did not actually provide for the emissions reductions necessary to achieve RACT-level reductions. Since then, the District has amended, and the EPA has approved, the RECLAIM rules to achieve greater aggregate emissions reductions from the sources in the program, and based on the District's evaluation of the amended program as set forth in the 2017 RACT Supplement, we have concluded that the RECLAIM rules, as amended, meet the RACT requirement in sections 182(b)(2) and 182(f) with respect to major stationary sources of NOX in the South Coast.

Comment #2: Earthjustice contends that approval of the South Coast RACT demonstration would be arbitrary and capricious because the RECLAIM rules, as amended in 2015, do not achieve aggregate emissions reductions of NOX equivalent to those that would be achieved through implementation of RACT level of control at each major NOX source in the South Coast. Earthjustice summarized that, as a part of the District's rule development process culminating in the 2015 RECLAIM amendments, SCAQMD analyzed whether its program achieved Best Available Retrofit Control Technology (BARCT) controls. The commenter points out that the District's analysis identified refineries as having the largest total NOX emissions and as holding the largest percentage of RTCs, but that the RECLAIM program had excess RTCs that resulted in refinery facilities not needing to achieve actual emission reductions.

Earthjustice points out that SCAQMD's BARCT assessment concluded that a 14 tpd “shave” from the program was needed to be equivalent to a traditional command-and-control regulatory approach. Earthjustice further asserts that if readily available BARCT equipment were applied to sources of pollution in the program, emissions would have been at 9.5 tpd instead of 20.7 tpd. Earthjustice comments that, although the SCAQMD staff recommended a 14 tpd shave, the Governing Board adopted a 12 tpd shave instead. Earthjustice further states that the record shows that the 12 tpd shave does not sufficiently result in RACT level controls for the NOX RECLAIM universe and that the EPA has a record before it showing that at least a 14 tpd shave is necessary to achieve what the District confirmed was necessary to assure implementation of RACT-equivalent level of controls that the BARCT assessment demonstrated was necessary. Moreover, Earthjustice states that the record shows that the pace of the shave interferes with attainment of the 2006 PM2.5 standard.

Response #2: We disagree with Earthjustice's implication that the terms RACT and BARCT are interchangeable and its assertion that the record shows a 14 tpd shave is needed to meet RACT.

BARCT is a term used by the State of California and is defined as “an emission limitation that is based on the maximum degree of reduction achievable, taking into account environmental, energy, and economic impacts by each class or category of source.” 17 [Emphasis added.] By comparison, the EPA defines RACT as the lowest emission limitation that a particular source is capable of meeting by the application of control technology that is reasonably available considering technological and economic feasibility. 44 FR 53762 (September 17, 1979). The EPA has historically not treated these terms interchangeably and has generally found that BARCT level of control meets or exceeds RACT level of control.18

We note that SCAQMD determined in its December 4, 2015 Draft Final Staff Report that only four out of an estimated 51 boilers/heaters were retrofitted with selective catalytic reduction to reduce NOX emissions to comply with BARCT.19 The staff report does not discuss RACT in the context of the RECLAIM program. Therefore, we disagree with the commenter that the December 4, 2015 Draft Final Staff Report or elsewhere in the record that SCAQMD had determined that the 2015 amendments to the RECLAIM program fail to implement RACT. The TSD associated with our June 15, 2017 proposed rule explains how the RECLAIM program, as amended in 2015, fulfills the RACT requirement based on the District's re-evaluation of the 2015 BARCT reassessment in terms of RACT, rather than BARCT. We find the District evaluation of the amended RECLAIM program to be acceptable as the basis to conclude that the amended program provides equivalent emissions reductions in the aggregate to those that would be achieved through implementation of RACT at all major NOX sources in the South Coast.

Lastly, we disagree with Earthjustice's assertion that the EPA should not approve the South Coast RACT demonstration because the pace of the NOX shave would interfere with attainment of the 2006 PM2.5 standard. This final rule addresses a requirement applicable to ozone nonattainment areas, not PM2.5 areas. With respect to the latter pollutant, the EPA will consider the pace of NOX reductions in the 2015 RECLAIM rule amendments in the context of our evaluation of the reasonable further progress (RFP) and attainment demonstrations in the PM2.5 portion of the recently submitted 2016 South Coast Air Quality Management Plan.

Comment #3: Earthjustice contends that the District has failed to remedy the problem of credits from shutdowns that have occurred prior to 2016 and notes that such credits have had the effect of depressing credit prices and thereby allowing major sources, particularly refineries, to avoid installation of BARCT/RACT controls like SCRs. Earthjustice identifies California Portland Cement as one of the most significant shutdown facilities whose credits (2.5 tons per day) have led to this problem and contends that refineries and other facilities continue to use credits from that shutdown facility to avoid installation of BARCT/RACT controls. To remedy this problem, Earthjustice asserts that the pre-2016 credits, including those from California Portland Cement, must be removed to achieve BARCT/RACT level of control.

Response #3: The RECLAIM rule amendments adopted by the District in 2016 were enacted specifically to avoid the effect of shutdown credits depressing credit prices and allowing sources to avoid installation of pollution controls, but we recognize that the 2016 amendments act prospectively and do not address credits from shutdowns that occurred prior to the amendments. Nonetheless, the 12-tpd shave in the NOX annual allotments enacted by the District in 2015 discounts RTCs to a much greater extent than necessary to simply address the significant market effect of credits from pre-2016 shutdowns. As such, the problem has been adequately addressed and the associated disincentive to install controls has been removed.20

Comment #4: Earthjustice contends that, while in some cases BARCT may exceed RACT, BARCT does not exceed RACT with respect to the District's 2015 BARCT assessment controls because the BARCT level controls established in the 2015 BARCT analysis are cost-effective and have been achieved in practice. Earthjustice objects to the District's general approach to distinguishing between BARCT and RACT-level controls in the 2017 RACT Supplement as artificially narrow on the grounds that the analysis only focuses on regulations that are adopted by either SCAQMD or other California Air Districts. Earthjustice objects to this approach because the District itself has generally abandoned adopting command-and-control regulations for NOX RECLAIM facilities and the limited geographic focus of the evaluation on California-only air districts for more stringent controls is not supported by the Clean Air Act. The focus on rules, Earthjustice contends, distracts from the actual technology, which the District has determined are cost effective and have been used in practice. More specifically, Earthjustice states that the District “has not articulated how the seven of ten BARCT level controls fail to meet the RACT determination.” Lastly, Earthjustice asserts that the RECLAIM program has a number of features that together keep credit prices low, which inhibits the installation of controls.

Response #4: We agree that, in its 2015 BARCT reassessment, the District identified 10 equipment categories as capable of further emissions reductions (beyond the 2005 NOX emission factors) and that the District's analysis was based on retrofit technologies that the District had concluded were cost-effective and achieved in practice. However, the District's determinations in this regard were for BARCT, not RACT, i.e., the emission limitations and associated retrofit technologies were found by the District to be cost-effective and achieved in practice to reduce emissions to the maximum degree of reduction achievable, not to the degree of reduction achievable through reasonably available controls.

There is no universal method for evaluating a cap-and-trade program for RACT equivalence, and we find the District's approach, i.e., distinguishing between BARCT and RACT on the basis of whether the BARCT controls have been adopted by the District itself or any other California Air District, to be reasonable. The commenter objects to the District's basic approach as too narrow because the District should have considered the rules adopted by air agencies in other states. However, we believe that the SCAQMD's approach is reasonable because the SCAQMD has, for the purposes of meeting other CAA requirements such as demonstrating attainment, continued to tighten emission limits in its own command-and-control rules to reduce emissions from many of the same types of sources that are included in the RECLAIM program,21 and the emission limits in its own command-and-control rules thus provide a basis for comparison with RECLAIM emissions factors. Also, the larger California Air Districts, such as the San Joaquin Valley Unified Air Pollution Control District, are similar to the SCAQMD in that they have been designated nonattainment for the ozone NAAQS for several decades and have conducted several rounds of RACT review for their rules, which, therefore, provide another appropriate basis of comparison with RECLAIM emissions factors.

Nonetheless, while we believe the SCAQMD's approach in the 2017 RACT Supplement is reasonable, we have provided additional review of the seven RECLAIM categories for which the District concluded that the 2005 RECLAIM factors represent RACT level of control. The seven categories include four from the refinery sector: Fluid catalytic cracking units (FCCUs), boilers and heaters, coke calciners, and sulfur recovery unit/tail gas (SRU/TG) incinerators, and three from the non-refinery sector: Glass melting furnaces, sodium silicate furnaces, and metal heating treating.

At the outset, we note that, while the EPA has not established a simple cost-effectiveness threshold to determine RACT in all applications, the incremental cost effectiveness estimates for three of the seven categories (refinery boilers and heaters, coke calciners, and SRU/TG incinerators) to achieve 2015 BARCT (relative to the 2005 BARCT) exceed $22,000 per ton 22 and are well above any such estimates that the Agency has generally considered appropriate for determining RACT.23 As such, we agree with the District that the 2005 RECLAIM factors for these three categories represent at least RACT level of control. We provide our review of the four other categories in the following paragraphs.

First, with respect to FCCUs, the District's 2015 BARCT staff report compiled and evaluated emissions limits adopted throughout the U.S. and internationally.24 The most stringent limits for FCCUs identified therein are in the 8-10 ppm range, which is equivalent to the 85% reduction that was included in the 2005 RECLAIM amendments for this category.25 As such, we find that the 2005 RECLAIM factors for refinery FCCUs reflect RACT level of control. For comparison purposes, the 2015 BARCT RECLAIM factor for FCCUs is 2 ppm.

Second, with respect to glass melting furnaces, the RECLAIM NOX factor for the container glass melting category prior to the 2015 RECLAIM amendments was 1.2 pound of NOX per ton of glass pulled.26 The EPA agrees that this limit meets RACT since it is consistent with the 1.5 pound of NOX per ton of glass limit 27 we approved for San Joaquin Valley Unified Air Pollution Control District's Rule 4354 (“Glass Melting Furnaces”) as implementing RACT for an Extreme ozone nonattainment area. For comparison purposes, the 2015 BARCT RECLAIM factor for glass melting furnaces is 80% reduction (or 0.24 lb/ton glass produced).

Third, with respect to metal heat treating furnaces, the 2005 RECLAIM BARCT emission factor for this category is 45 ppm.28 We find that this limit is consistent with the 60 ppm limit for metal melting furnaces in the District's corresponding command-and-control rule, Rule 1147 (“NOX Reductions from Miscellaneous Sources”).29 The 2015 BARCT RECLAIM factor for metal heat treating furnaces >150 MMBtu/hr is 9 ppm.

Fourth, with respect to sodium silicate furnaces, we note that the incremental emissions reductions (0.09 tons per day) are too small to affect the conclusion of the analysis because the SCAQMD's ending allocation under the 2015 RECLAIM amendments of 14.5 tons per day is 0.3 tons per day less (i.e., more stringent) than the hypothetical ending allocation reflecting RACT level of control (i.e., 14.8 tons per day). Thus, even if we were to assume that the 2015 RECLAIM factor for this category (80% reduction) represents RACT, the SCAQMD's 2015 ending allocation (14.5 tons per day) would still be less than the hypothetical ending allocation reflecting RACT level of control (14.8 minus 0.09 or 14.71 tons per day).

Therefore, we do not believe that the comment has demonstrated that controls that SCAQMD labels BARCT, can be assumed to also be RACT. Rather, we think it is appropriate to generally rely on the more involved RACT analysis performed by different agencies at the time of rule adoption or preparation of a RACT SIP. As such, we believe it is reasonable to assume that a control is beyond RACT if it has not yet been adopted by air districts in California.

Lastly, with respect to the issue of excess credits in the RECLAIM market and related delays in the installation of controls, please see our response to comment #3.30

Comment #5: Citing CAA section 110(a)(2)(E), Earthjustice asserts that the EPA can only approve a SIP revision if it determines that the provision is not inconsistent with state law. Earthjustice contends that the current proposal violates California law because it is not equivalent to BARCT and does not achieve command-and-control equivalence as mandated by California's Health and Safety Code. As such, Earthjustice contends that the EPA cannot make the determination required in section 110 of the Act that the approval not interfere with compliance with state law.

Response #5: We disagree that we must determine under CAA section 110 that a SIP or SIP revision is not inconsistent with state law, or that the approval would not interfere with compliance with state law, prior to approval. Rather, in reviewing SIPs and SIP revisions, the EPA must determine that the SIP or SIP revision is supported by necessary assurances that the state or relevant local or regional agency has adequate legal authority under state and local law to carry out the SIP or SIP revision (and is not prohibited by any provision of federal or state law from carrying out such SIP or portion thereof).31

First, alleged inconsistency with state law is relevant to the EPA in the context of our SIP review only if it undermines the legal authority under state or local law to carry out the SIP. In this instance, compliance with the RACT requirement in the South Coast depends in part on the legal authority of the SCAQMD to carry out the RECLAIM rules, as amended in 2015 and 2016,32 and as to the amended RECLAIM rules, the EPA has been provided the necessary assurances by CARB that the District has the legal authority to carry out the rules. See CARB Executive Order S-17-002 (dated March 16, 2017) adopting the amended 2015 and 2016 RECLAIM rules as a revision to the California SIP.33 For that reason, we find that the 2016 AQMP RACT SIP, as supplemented by the 2017 RACT Supplement and negative declarations, is supported by adequate legal authority and, thus, meets the corresponding requirements in CAA section 110(a)(2)(E).

Under section 110(k)(3) of the Act, and for the reasons set forth in the proposed rule and summarized above, the EPA is taking final action to approve certain revisions to the California SIP submitted by CARB to address the RACT requirements for the 2008 ozone standard for the South Coast and Coachella Valley nonattainment areas. More specifically, we are approving the RACT demonstration in the 2016 AQMP RACT SIP, as supplemented in the 2017 RACT Supplement, certain permit conditions for two power plants in Coachella Valley included with the 2017 RACT Supplement, and two negative declarations (for the CTG for shipbuilding and repair operations and for the paper coating portion of the CTG for paper, film and film coatings) because collectively they fulfill RACT SIP requirements under CAA sections 182(b) and (f) and 40 CFR 51.1112 for the South Coast and Coachella Valley for the 2008 ozone NAAQS.

In this rule, the EPA is finalizing regulatory text that includes incorporation by reference. In accordance with the requirements of 1 CFR 51.5, the EPA is finalizing the incorporation by reference of certain permit conditions for two stationary sources in Coachella Valley described in the amendments to 40 CFR part 52 set forth below. The EPA, has made, and will continue to make, these documents available through www.regulations.gov and at the EPA Region IX Office (please contact the person identified in the FOR FURTHER INFORMATION CONTACT section of this preamble for more information).

Under the Clean Air Act, the Administrator is required to approve a SIP submission that complies with the provisions of the Act and applicable federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, the EPA's role is to approve state choices, provided that they meet the criteria of the Clean Air Act. Accordingly, this action merely approves SIP revisions as meeting federal requirements and does not impose additional requirements beyond those imposed by state law. For that reason, this action:

• Is not a “significant regulatory action” subject to review by the Office of Management and Budget under Executive Orders 12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011);

• Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);

• Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.);

• Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Public Law 104-4);

• Does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999);

• Is not an economically significant regulatory action based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997);

• Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001);

• Is not subject to requirements of Section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application of those requirements would be inconsistent with the Clean Air Act; and

• Does not provide the EPA with the discretionary authority to address disproportionate human health or environmental effects with practical, appropriate, and legally permissible methods under Executive Order 12898 (59 FR 7629, February 16, 1994).

In addition, the SIP is not approved to apply on any Indian reservation land or in any other area where the EPA or an Indian tribe has demonstrated that a tribe has jurisdiction. In those areas of Indian country, this rule does not have tribal implications and will not impose substantial direct costs on tribal governments or preempt tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the Small Business Regulatory Enforcement Fairness Act of 1996, generally provides that before a rule may take effect, the agency promulgating the rule must submit a rule report, which includes a copy of the rule, to each House of the Congress and to the Comptroller General of the United States. The EPA will submit a report containing this action and other required information to the U.S. Senate, the U.S. House of Representatives, and the Comptroller General of the United States prior to publication of the rule in the Federal Register. A major rule cannot take effect until 60 days after it is published in the Federal Register. This action is not a “major rule” as defined by 5 U.S.C. 804(2).

Under section 307(b)(1) of the Clean Air Act, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by November 20, 2017. Filing a petition for reconsideration by the Administrator of this final rule does not affect the finality of this rule for the purposes of judicial review nor does it extend the time within which a petition for judicial review may be filed, and shall not postpone the effectiveness of such rule or action. This action may not be challenged later in proceedings to enforce its requirements (see section 307(b)(2)).

Chapter I, title 40 of the Code of Federal Regulations is amended as follows:

The legal basis of this rulemaking is provided by Title 46 of United States Code (U.S.C.), section 2103. Section 2103 gives the Secretary of the department in which the Coast Guard is operating regulatory authority to carry out the provisions of Title 46, subtitle II (Vessels and Seamen) of the U.S.C., in which vessel documentation statutes are located. The Secretary's authority is delegated to the Coast Guard by Department of Homeland Security Delegation No. 0170.1, para. II (92.a). The purpose of this rule is to make non-substantive edits to: (1) Align the Coast Guard's vessel documentation regulations with current statutes on that subject; (2) correct typographical errors; and (3) align procedural requirements with current Coast Guard practice.

We did not publish a notice of proposed rulemaking for this rule. Under Title 5 of United States Code (U.S.C.) section 553(b)(A), the Coast Guard finds that this rule is exempt from notice and public comment rulemaking requirements, because these changes involve rules of agency organization, procedure, or practice. In addition, the Coast Guard finds that notice and comment procedures are unnecessary under 5 U.S.C. 553(b)(B), as this rule consists only of technical and editorial corrections, organizational, and conforming amendments, and that these changes will have no substantive effect on the public. Under 5 U.S.C. 553(d)(3), the Coast Guard finds that, for the same reasons, good cause exists for making this final rule effective upon publication in the Federal Register.

On October 18, 2013, the Maritime Law Association, a private group consisting primarily of maritime lawyers, petitioned the Coast Guard to open a rulemaking to make numerous changes to our vessel documentation regulations.1 The Coast Guard granted the petition on November 6, 2013, and shortly thereafter, began working with members of the Maritime Law Association to identify specifically what changes should be made. Many of the changes the group requested involve significant substantive changes that may be the subject of future regulatory action. However, part of the review process also revealed several instances where the Coast Guard could currently make non-substantive technical corrections.

“Vessel documentation” refers to the system under which a vessel receives a Government certificate of documentation (COD). This certificate is required for the operation of a vessel of at least 5 net tons in certain trades including: (1) Fisheries on the navigable waters of the United States or its Exclusive Economic Zone; (2) foreign trade or trade with U.S. overseas territories; and (3) coastwise trade (trade between U.S. ports without leaving U.S. territorial waters) as described in 46 U.S.C. 12102 and 46 U.S.C. chapter 121, subchapter II. The COD is also a required element, in 46 U.S.C. 31322, to establish a vessel's entitlement to preferred mortgage status. Under 46 U.S.C. 31326, preferred mortgages have priority over other liens on vessels, and they offer an enhancement to the security available to lenders.

This final rule makes 35 non-substantive changes to 19 sections in 46 CFR part 67. The changes correct omissions, misspellings, or inaccurate references caused by unintentional typographical errors and make small edits for additional clarity. The changes also update referenced material, such as treaty citations and web addresses. Over the course of several decades, through various laws, Congress has undertaken the task of codifying U.S. shipping laws into positive law. The two most significant of these acts were Public Law 98-89 (1986), which codified subtitle II of Title 46 into positive law, and Public Law 109-304 (2006), which completed the process of codifying all of Title 46 into positive law. Due to the recodification of Title 46, several 46 CFR part 67 regulations currently contain inaccurate statutory citations. A crosswalk between pre-codified and codified provisions of Title 46 is available in the disposition tables in 46 U.S.C.2

The changes made by this rule also reflect the elimination of citizenship requirements for mortgagees by Public Law 104-324, section 1113 (1996). Since the issuance of Public Law 104-324, the National Vessel Documentation Center (NVDC) has allowed vessel owners to mortgage their vessels to non-citizens, and it has not restricted the eligibility of a vessel mortgaged to a non-citizen to earn registry or coastwise endorsements, even though 33 CFR 67.17(c) and 67.19(d)(3) continue to explicitly state these restrictions. Therefore, amending these sections will align regulatory text with the current and longstanding 20-year practice of the NVDC, consistent with the statutory requirements, and these changes will result in no impact on industry.

This rule also makes changes to reflect the elimination of renewal decals and address labels for CODs issued by the NVDC. In 2001, the NVDC began to use a new database, Vessel Documentation System 1.0, and introduced the current version of the COD (66 FR 15625, March 20, 2001). This information technology system and recordkeeping form made the use of decals and labels unnecessary; therefore, the NVDC stopped requiring them, even though the relevant sections of part 67 continued to reference them. Amending 46 CFR 67.163(c) and 67.311 will align regulatory text with NVDC's current practice, and these changes will result in no impact on industry.

The following table shows the complete list of sections in 46 CFR part 67 that we are amending, the changes we are making, the reasons for those changes, and their impacts.

In association with the changes made by the recodification of title 46, the Coast Guard is updating its list of authority citations for 46 CFR part 67. For a cross-walk between the changes, please see the disposition tables for title 46 and the Historical and Revision Notes for the applicable sections in the U.S.C.3

We developed this rule after considering numerous statutes and Executive orders related to rulemaking. Below we summarize our analyses based on these statutes or Executive orders.

Executive Orders 12866 (“Regulatory Planning and Review”) and 13563 (“Improving Regulation and Regulatory Review”) direct agencies to assess the costs and benefits of available regulatory alternatives and, if regulation is necessary, to select regulatory approaches that maximize net benefits (including potential economic, environmental, public health and safety effects, distributive impacts, and equity). Executive Order 13563 emphasizes the importance of quantifying both costs and benefits, of reducing costs, of harmonizing rules, and of promoting flexibility. Executive Order 13771 (“Reducing Regulation and Controlling Regulatory Costs”) directs agencies to reduce regulation and control regulatory costs and provides that “for every one new regulation issued, at least two prior regulations be identified for elimination, and that the cost of planned regulations be prudently managed and controlled through a budgeting process.”

The Office of Management and Budget (OMB) has not designated this rule a significant regulatory action under section 3(f) of Executive Order 12866. Accordingly, OMB has not reviewed it. As this rule is not a significant regulatory action, this rule is exempt from the requirements of Executive Order 13771. See OMB's Memorandum “Guidance Implementing Executive Order 13771, Titled `Reducing Regulation and Controlling Regulatory Costs'” (April 5, 2017). This rule involves non-substantive changes and internal agency practices and procedures; it will not impose any additional costs on the public. The benefit of the non-substantive changes is increased clarity of regulations.

This rule is not preceded by a notice of proposed rulemaking and, therefore, is exempt from the requirements of the Regulatory Flexibility Act (5 U.S.C. 601-612). The Regulatory Flexibility Act does not apply when notice and comment rulemaking is not required.

Under section 213(a) of the Small Business Regulatory Enforcement Fairness Act of 1996 (Pub. L. 104-121), we want to assist small entities in understanding this rule so that they can better evaluate its effects on them. The Coast Guard will not retaliate against small entities that question or complain about this rule or any policy or action of the Coast Guard.

Small businesses may send comments on the actions of Federal employees who enforce, or otherwise determine compliance with, Federal regulations to the Small Business and Agriculture Regulatory Enforcement Ombudsman and the Regional Small Business Regulatory Fairness Boards. The Ombudsman evaluates these actions annually and rates each agency's responsiveness to small business. If you wish to comment on actions by employees of the Coast Guard, call 1-888-REG-FAIR (1-888-734-3247).

This rule calls for no new or modified collection of information under the Paperwork Reduction Act of 1995, 44 U.S.C. 3501-3520.

A rule has implications for federalism under Executive Order 13132 (“Federalism”) if the rule has a substantial direct effect on State or local governments and would either preempt State law or impose a substantial direct cost of compliance on them. We have analyzed this rule under Executive Order 13132 and have determined that it does not have implications for federalism.

The Unfunded Mandates Reform Act of 1995, 2 U.S.C. 1531-1538, requires Federal agencies to assess the effects of their discretionary regulatory actions. In particular, the Act addresses actions that may result in the expenditure by a State, local, or tribal government, in the aggregate, or by the private sector of $100,000,000 (adjusted for inflation) or more in any one year. Though this rule will not result in such an expenditure, we do discuss the effects of this rule elsewhere in this preamble.

This rule will not cause a taking of private property or otherwise have taking implications under Executive Order 12630, Governmental Actions and Interference with Constitutionally Protected Property Rights.

This rule meets applicable standards in sections 3(a) and 3(b)(2) of Executive Order 12988 (“Civil Justice Reform”), to minimize litigation, eliminate ambiguity, and reduce burden.

We have analyzed this rule under Executive Order 13045 (“Protection of Children from Environmental Health Risks and Safety Risks”). This rule is not an economically significant rule and would not create an environmental risk to health or risk to safety that might disproportionately affect children.

This rule does not have tribal implications under Executive Order 13175 (“Consultation and Coordination with Indian Tribal Governments”), because it does not have substantial direct effects on one or more Indian tribes, on the relationship between the Federal Government and Indian tribes, or on the distribution of power and responsibilities between the Federal Government and Indian tribes.

We have analyzed this rule under Executive Order 13211 (“Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use”). We have determined that it is not a “significant energy action” under that order because it is not a “significant regulatory action” under Executive Order 12866 and is not likely to have a significant adverse effect on the supply, distribution, or use of energy. The Administrator of OMB's Office of Information and Regulatory Affairs has not designated it as a significant energy action.

The National Technology Transfer and Advancement Act, codified as a note to 15 U.S.C. 272, directs agencies to use voluntary consensus standards in their regulatory activities unless the agency provides Congress, through OMB, with an explanation of why using these standards would be inconsistent with applicable law or otherwise impractical. Voluntary consensus standards are technical standards (e.g., specifications of materials, performance, design, or operation; test methods; sampling procedures; and related management systems practices) that are developed or adopted by voluntary consensus standards bodies. This rule does not use technical standards. Therefore, we did not consider the use of voluntary consensus standards.

We have analyzed this rule under Department of Homeland Security Management Directive 023-01 and Commandant Instruction M16475.lD (COMDTINST M16475.1D), which guide the Coast Guard in complying with the National Environmental Policy Act of 1969 (42 U.S.C. 4321-4370f), and have made a determination that this action is one of a category of actions that do not individually or cumulatively have a significant effect on the human environment. A Record of Environmental Consideration supporting this determination is available in the docket. This rule is categorically excluded under Chapter 2, Section B, Paragraph 2 (Categorical Exclusions), and Figure 2-1 (Coast Guard Categorical Exclusions), paragraph (34)(a) and (34)(d) of the Instruction.

This final rule involves technical amendments to the Coast Guard's vessel documentation regulations. Certificates of Documentation allow the operation of vessels in certain trades, provide evidence of vessel nationality, and permit vessels to be subject to preferred mortgages. The technical amendments presented in this rulemaking entail editorial or procedural changes that: (1) Align Coast Guard regulations with current vessel documentation statutes; (2) correct non-substantive typographical errors; and (3) harmonize procedural requirements with current Coast Guard practice. These amendments collectively promote the Coast Guard's maritime safety, security, and environmental protection missions by rendering the Coast Guard's vessel documentation system more effective.

For the reasons discussed in the preamble, the Coast Guard amends 46 CFR part 67 as follows:

This is a summary of the Commission's Report and Order, ET Docket No. 15-26, FCC 17-94, adopted July 13, 2017 and released July 14, 2017. The full text of this document is available for public inspection and copying during normal business hours in the FCC Reference Center (Room CY-A257), 445 12th Street SW., Washington, DC 20554, or by downloading the text from the Commission's Web site at http://transition.fcc.gov/Daily_Releases/Daily_Business/2017/db0714/FCC-17-94A1.pdf. Alternative formats are available for people with disabilities (Braille, large print, electronic files, audio format) by sending an email to [email protected] or calling the Commission's Consumer and Governmental Affairs Bureau at (202) 418-0530 (voice), (202) 418-0432 (TTY).

1. On February 3, 2015, the Commission adopted a Notice of Proposed Rulemaking (NPRM) in this proceeding. 80 FR 12120, March 6, 2015. In the Report and Order, the Commission amended the United States Table of Frequency Allocations (U.S. Table) in § 2.106 and several related service rules to establish a comprehensive and consistent set of rules and policies for radar operations in the 76-81 GHz band. The following are the major actions that the Commission took to support the deployment in the 76-81 GHz band of advanced vehicular radar applications and certain non-vehicular fixed and mobile radar applications for use at airports:

• Allocated the 77.5-78 GHz band to the Radiolocation Service on a primary basis in the U.S. Table to provide a contiguous five gigahertz band at 76-81 GHz for radar operations.

• Allowed vehicular radars and certain non-vehicular fixed and mobile radars used at airports to operate in the entire 76-81 GHz band.

• Consolidated radar operations in the 76-81 GHz band under part 95 of the Commission's rules to be licensed-by-rule and protected from interference with the same technical parameters as currently specified for 76-77 GHz radars in part 15 of the rules.

• Restricted fixed radar operations to airport air operations areas to prevent such radars signals from illuminating public roadways and causing harmful interference to vehicular radar operations.

• Reduced the maximum equivalent isotropically radiated power (EIRP) of amateur and amateur satellite operations in the 76-81 GHz band to match that of radar operations in the 76-81 GHz band to reduce the potential for these amateur operations to cause harmful interference to radar operations in the band.

2. In the Report and Order, the Commission amended parts 1, 2, 15, 90, 95, and 97 of its rules to facilitate the deployment in the 76-81 GHz band of advanced vehicular radar applications and certain fixed and mobile radars in airport air operations areas. These actions are described in greater detail below.

3. As proposed in the NPRM, the Commission allocated the 77.5-78 GHz band to the Radiolocation Service (RLS) on a primary basis in the U.S. Table. This action made the entire 76-81 GHz band available for licensed radar applications on a primary basis nationwide and brought the U.S. Table into agreement with the International Table of Frequency Allocations. In response to commenters' concerns about the potential for interference from amateur operations to vehicular radar operations in the 76-81 GHz band, the Commission changed the Amateur Service and Amateur Satellite Service allocations in the 77.5-78 GHz band of the U.S. Table from primary to secondary status to match the secondary Amateur Service and Amateur Satellite Service allocations in the remainder of the 76-81 GHz band. As secondary users in the 76-81 GHz band, amateurs will have an obligation to operate in a manner that minimizes the potential for harmful interference to licensed radar applications that will operate under the primary RLS allocation throughout the entire 76-81 GHz band and Radio Astronomy Service (RAS) stations in the 76-81 GHz band, and cannot claim protection from harmful interference from any primary service. If amateur radio operators cause any harmful interference, they will be required to provide an immediate remedy, up to and including terminating their operations. As an added protection against potential interference from amateur operations to vehicular radar operations in the 76-81 GHz band, the Commission amended the part 97 Amateur Radio Service rules to specify a maximum EIRP of 55 dBm (316 Watts) that Amateur Service and Amateur Satellite Service stations in the 76-81 GHz band may transmit, the same as the allowable vehicular radar peak EIRP limit.

4. Although the Commission determined that the addition of the primary RLS allocation in the 77.5-78 GHz band did not raise any new interference considerations for RAS operations in the 76-81 GHz band, because there is no distinction between RAS use of the 77.5-78 GHz band and the remainder of the 76-81 GHz band it upgraded the secondary RAS allocation in the 77.5-78 GHz band to primary status to match the RAS allocations in the 76-77.5 GHz/78-81 GHz bands. By making the RLS and RAS co-primary throughout the 76-81 GHz band, the Commission provided regulatory consistency between the two services and eliminated the potential problem, in the event of harmful interference to the RAS due to vehicular radar operations, of determining protection rights in favor of addressing and mitigating the interference concern. However, since the Commission determined that addition of the primary RLS allocation in the 77.5-78 GHz band did not raise any new interference considerations that would justify upgrading the secondary Space Research Service (space-to-Earth) (SRS (space-to-Earth)) allocation in the 77.5-78 GHz band to primary status, the Commission maintained this service's current secondary status, consistent with the SRS (space-to-Earth) allocations in the remainder of the 76-81 GHz band. Given the size and scope of the automotive fleet in the United States as compared to the two RAS facilities that operate in the 76-81 GHz band, the Commission declined to adopt commenters proposals for an automatic or manual on/off switch and coordination zones in the vicinity of RAS observatories for vehicular radars that operate in the 76-81 GHz band.

5. As part of the Commission's efforts to consolidate future vehicular radar operations into the 76-81 GHz band, the NPRM noted that there is little or no use of vehicular radars in the 16.2-17.7 GHz and 46.7-46.9 GHz bands, and sought comment on modifying the Commission's part 15 rules to no longer approve vehicular radar devices for operation in these bands. Since no commenters opposed this suggestion, the Commission deleted the references to vehicular radar operations in the 16.2-17.7 GHz and 46.7-46.9 GHz bands from the Commission's part 15 rules and ceased accepting applications for equipment certification of such devices effective upon the adoption of the Report and Order. It prohibited the continued manufacture, importation, marketing, sale, and installation for use in the United States of such equipment in the 16.2-17.7 GHz band under the sole existing equipment authorization, FCC ID No. L2C0004TR. However, it grandfathered, for the life of the equipment, any vehicular radars that are already installed or in use under this authorization, thus allowing such systems to continue operating for the life of the vehicle or until the supply of existing equipment necessary for maintenance is exhausted.

6. As proposed in the NPRM, the Commission also phased out unlicensed wideband radars authorized under § 15.252 to operate in the 23.12-29 GHz and ultra-wideband (UWB) radars authorized under § 15.515 to operate in the 22-29 GHz band (collectively, “unlicensed 24 GHz wideband and UWB vehicular radars”). In response to commenters' concerns that ceasing certification of new unlicensed 24 GHz wideband and UWB vehicular radars beginning 30 days after publication of the final rules in the Federal Register, as proposed in the NPRM, would be insufficiently short, the Commission decided it will not certify new unlicensed 24 GHz wideband and UWB vehicular radar equipment on or after one year from the date of publication of the Report and Order in the Federal Register. In response to commenters' suggestions to, at a minimum, harmonize the phase-out of unlicensed 24 GHz wideband and UWB vehicular radars with the phase-out adopted for 24 GHz vehicular radars in the European Union (EU), the Commission decided to allow the manufacture, importation, marketing, sale, and installation of, as well as Class II permissive changes for, previously certified unlicensed 24 GHz wideband and UWB vehicular radar devices until January 1, 2022, consistent with the EU transition plan for 24 GHz vehicular radars. After January 1, 2022, the manufacture, importation, marketing, sale, and installation of, and Class II permissive changes for, these devices for use in the United States, with one limited exception regarding sale and installation for the repair/replacement of defective, damaged, or malfunctioning equipment, will not be permitted.

7. However, as proposed in the NPRM, the Commission decided to permit unlicensed 24 GHz wideband and UWB vehicular radars that are already installed or in use by January 1, 2022 to continue to operate in the vehicle. In that regard, the Commission provided a narrow exception to the phase-out requirements to permit, for the life of the vehicle, the continued sale and installation of unlicensed 24 GHz wideband and UWB radar devices for the exclusive purpose of repairing or replacing defective, damaged, or potentially malfunctioning equipment installed on or before January 1, 2022. This exception is available only when it is not possible to repair or replace the radar equipment designed to operate in the 24 GHz band with radar equipment designed to operate in the 76-81 GHz band, and is limited to the repair and replacement of unlicensed 24 GHz wideband and UWB vehicular radar equipment that has been certified for operation in the 24 GHz band. The Commission expects manufacturers to draw on existing stock of equipment that has been approved before January 1, 2022, but it will address requests for additional relief (e.g., manufacture, importation, or product redesign) on a case-by-case basis.

8. The Commission clarified that the proposal with regard to phasing out use of the 22-29 GHz band for wideband and UWB vehicular radar operations that operate under §§ 15.252 and 15.515 of the rules was not intended to apply to unlicensed radars that operate at 24.075-24.175 GHz and 24.0-24.25 GHz under §§ 15.245 and 15.249 of the rules, respectively. These rules, which are not being modified, authorize a wide variety of devices that include, but are not limited to, vehicular-specific radars. As such, the Commission will continue to certify radars that operate under these rules and they can continue to be used in vehicular applications.

9. Fixed Radars Operations. The NPRM proposed to adopt rules that would permit fixed infrastructure radar applications in all or part of the 76-81 GHz band if there was sufficient demand for such uses and studies could support sharing between vehicular and non-vehicular radar applications in the band. Although several commenters expressed interest in deploying fixed radar applications in the 76-81 GHz band at any location, there was substantial disagreement as to whether such applications could successfully coexist with vehicular radars. Many commenters opposed allowing fixed radar operations in the 76-81 GHz band, citing potential interference that could compromise the safe operation of vehicular radar systems. Although commenters asserted that they expected fixed radar manufacturers to design equipment that is technically identical to vehicular radars, the Commission stated that it could not guarantee that this would happen in practice since it neither proposed nor developed a record for the Commission to mandate device specifications and guidelines. Therefore, to prevent non-vehicular fixed radar applications outside of airport locations from causing harmful interference to vehicular radars and provide a more certain environment for the successful migration of vehicular radars to the 76-81 GHz band, the Commission decided to maintain the existing prohibition on non-vehicular fixed radar operations outside of airport air operations areas.

10. However, the Commission recognized the possibility that there may be situations in which fixed radars might be compatible with vehicular radars in the 76-81 GHz band, and did not foreclose exploration of such scenarios. The Commission acknowledged that, under careful coordination, it might be possible for fixed radars to operate in the band at carefully selected locations without causing harmful interference to vehicular radars, but noted that there was insufficient information in the record to develop the specific criteria for a successful coordination process. The Commission stated that it is open to the possibility that specific, limited fixed uses of 76-81 GHz radars outside of airport locations may be possible so long as it can be convinced that such use would not cause harmful interference to vehicular radar operations in the band.

11. Airport Radar Operations. Prior to adoption of the Report and Order, unlicensed FOD detection radar operations were operating as fixed devices in the 76-77 GHz band under part 15 of the rules, and could be authorized as either fixed or mobile devices on a licensed basis under the Commission's part 90 rules in the 78-81 GHz band, in airport air operations areas only. As proposed in the NPRM and supported by the record, the Commission decided to permit fixed and mobile FOD detection radar operations throughout the entire 76-81 GHz band on airport grounds only, under the same technical requirements as those provided for such operations in the 76-77 GHz band in part 15 of the Commission's rules. To minimize the potential for harmful interference to vehicular radar operations from expanded FOD detection radar operations, the Commission maintained the limitation that FOD detection radar operations occur only in airport locations that avoid illumination of public roadways (i.e., in airport air operations areas). This restriction will provide geographic separation between airport-based radar operations and vehicular radar operations on public roads, avoiding any possibility of harmful interference to vehicular radar operations in the 76-81 GHz band. As proposed in the NPRM and supported by the record, the Commission grandfathered for the life of the equipment, or until the supply of existing equipment necessary for maintenance is exhausted, any FOD detection radars that are already installed or in use. If entities want to operate existing FOD detection radars in the 77-78 GHz band, which has not previously been available for FOD detection radar use, such equipment would first have to be certified under the Commission's equipment authorization procedures to operate in the 77-78 GHz band under the part 95 rules.

12. The Commission also permitted the use of aircraft-mounted radar applications, referred to as “wingtip radars,” in the entire 76-81 GHz band with the same technical rules as FOD detection radars, as long as they are used in airport air operations areas while aircraft (including helicopters) are on the ground. These radars will be used to prevent and mitigate the severity of aircraft wingtip collisions while planes move between airport gates and runways. The Commission agreed with commenters that aircraft-mounted radar applications can help protect aircraft during taxiing and ground maneuvering, improve airport operations, and provide significant benefits to the airline industry and traveling public, while still protecting vehicular radars from harmful interference.

13. Based on the potential for airborne radar operations to interfere with RAS operations, the Commission decided not to permit the use of aircraft-mounted radars when the aircraft (or helicopter) is airborne. To provide greater assurance that parties will comply with the ground-based restriction for aircraft-mounted radars, the Commission also decided to require that aircraft-mounted radars include an automatic mechanism that discontinues all 76-81 GHz radar functions while the aircraft is airborne, which no commenters objected to, and one commenter indicated is technically feasible.

14. As proposed in the NPRM and supported by the majority of commenters, the Commission consolidated 76-81 GHz radar operations, except for Level Probing Radars (LPRs), under part 95 of the Commission's rules to be licensed-by-rule and protected from interference. Radar applications operating in the 76-81 GHz range will now be governed by Subpart M, The 76-81 GHz Radar Service, in part 95 of the rules. LPRs, which are authorized by § 15.256 to operate in a variety of frequency ranges, including the 75-85 GHz band, and can coexist with vehicular radar operations, will remain authorized to operate on an unlicensed basis.

15. A licensed-by-rule approach under part 95 will provide a level of interference protection to 76-81 GHz radar operations that the Commission's part 15 rules cannot provide since unlicensed users must accept interference from licensed and unlicensed users, whereas under part 95, primary licensed users are protected from interference from secondary and unlicensed users. A licensed-by-rule approach will also reduce the application and licensing burdens associated with authorizing radar operations under an individual license basis, and create time and cost efficiencies for deployment of these important services. Given that FOD detection radar operations are restricted to airport air operations areas that do not have public vehicle access, and considering the narrow beamwidths, highly directional antennas, and large signal propagation losses at relatively short distances of radar operations in the 76-81 GHz band, the Commission saw no need to require licensed FOD detection radars to coordinate with other licensed services or exclude FOD detection radars from part 95 regulation.

16. Technical Rules. As proposed in the NPRM, the Commission adopted technical rules for the newly expanded radar band that mirrored those currently provided for unlicensed vehicular radars and FOD detection radars in the 76-77 GHz band under the part 15 rules. Specifically, the Commission adopted the same average (50 dBm) and peak (55 dBm) EIRP emissions limits for radar applications in the entire 76-81 GHz band as is currently specified in the part 15 rules for unlicensed vehicular radars in the 76-77 GHz band. The Commission also adopted other technical rules for the newly expanded radar band that mirrored those currently provided under part 15, including unwanted emissions limits, equipment certification, and radiofrequency exposure evaluation. Consistent with the NPRM, the new part 95 rules do not specify distinct spectrum blocks in the 76-81 GHz band for particular radar operations such as LRR and SRR, or FOD detection and aircraft-mounted radars. Instead, the Commission chose to rely on market forces and standardization processes to drive radars use of the band in accordance with application needs and the state of the technology, and decided that interested parties can determine whether particular segments of the 76-81 GHz band should be designated exclusively for LRR or SRR applications, or for FOD detection or aircraft-mounted radars. Neither LRR applications nor aircraft-mounted radars are restricted to operating within a one-gigahertz block of spectrum within the 76-81 GHz band, as suggested by some commenters.

17. Vehicular and FOD detection radars currently certified under part 15 to operate in the 76-77 GHz band need not be recertified under part 95 to continue to operate in the band. These devices may continue their operations, but will now do so on a licensed-by-rule basis and be entitled to interference protection from amateur operations in the 76-81 GHz band. Any changes for such previously certified devices will need to comply with the applicable part 95 rules.

18. This document does not contain any new or modified information collections subject to the Paperwork Reduction Act of 1995 (PRA), Public Law 104-13.

19. The Commission will send a copy of the Report and Order in a report to be sent to Congress and the Government Accountability Office pursuant to the Congressional Review Act, see 5 U.S.C. 801(a)(1)(A).

20. The Regulatory Flexibility Act of 1980 (RFA) requires that an agency prepare a regulatory flexibility analysis for notice and comment rulemakings, unless the agency certifies that “the rule will not, if promulgated, have a significant economic impact on a substantial number of small entities.” Accordingly, the Commission has prepared a Final Regulatory Flexibility Analysis (FRFA), set forth in Appendix B of the Report and Order concerning the possible impact of the rule changes.

21. Accordingly, it is ordered that pursuant to sections 1, 2, 4(i), 301, 302(a), and 303(f) of the Communications Act of 1934, 47 U.S.C. 151, 152, 154(i), 301, 302(a), and 303(f), the Report and Order in ET Docket No. 15-26 is hereby adopted.

22. It is further ordered that parts 1, 2, 15, 90, 95, and 97 of the Commission's rules, 47 CFR parts 1, 2, 15, 90, 95, and 97 are amended, effective October 20, 2017, except as otherwise specified.

For the reasons discussed in the preamble, the Federal Communications Commission amends 47 CFR parts 1, 2, 15, 90, 95, and 97 as follows:

The revision and addition read as follows:

Executive Summary

Why we need to publish a rule. Under the Endangered Species Act, 16 U.S.C. 1531 et seq., a species or subspecies may warrant protection through listing if it is endangered or threatened throughout all or a significant portion of its range. Critical habitat shall be designated, to the maximum extent prudent and determinable, for any species determined to be an endangered or threatened species under the Act.

This rule finalizes the listing of the iiwi (Drepanis coccinea) as threatened under the Act because of current and future threats, and listing can only be done by issuing a rule. The iiwi no longer occurs across much of its historical range, and faces a variety of threats in the form of diseases and impacts to its remaining habitat.

Delineation of critical habitat requires, within the geographical area occupied by the species, identification of the physical or biological features essential to the species' conservation. A careful assessment of the biological needs of the species and the areas that may have the physical or biological features essential for the conservation of the species and that may require special management considerations or protections, and thus qualify for designation as critical habitat, is particularly complicated in this case by the ongoing and projected effects of climate change and will require a thorough assessment. We require additional time to analyze the best available scientific data in order to identify specific areas appropriate for critical habitat designation and to analyze the impacts of designating such areas as critical habitat. Accordingly, we find designation of critical habitat for the iiwi to be “not determinable” at this time.

What this document does. This document lists the iiwi as a threatened species. We previously published a 90-day finding and a 12-month finding and proposed listing rule for the iiwi. Those documents assessed all available information regarding status of and threats to the iiwi.

The basis for our action. Under the Act, we can determine that a species is an endangered or threatened species based on any of five factors: (A) The present or threatened destruction, modification, or curtailment of its habitat or range; (B) Overutilization for commercial, recreational, scientific, or educational purposes; (C) Disease or predation; (D) The inadequacy of existing regulatory mechanisms; or (E) Other natural or manmade factors affecting its continued existence. We have determined that the primary threats to the iiwi are its susceptibility to avian malaria (Factor C) and the expected reduction in disease-free habitat as a result of increased temperatures caused by climate change (Factor E). Although not identified as primary threat factors, rapid ohia death, a fungal disease that kills the tree species required by iiwi for nesting and foraging, and impacts from nonnative invasive plants and feral ungulates, contribute to the degradation and curtailment of the iiwi's remaining, disease-free native ohia forest habitat, exacerbating threats to the species' viability.

Peer review and public comment. We sought comments on our proposal from eight independent specialists to ensure that our designation is based on scientifically sound data, assumptions, and analyses. We also considered all comments and information received during the public comment period.

A species status report for the iiwi was prepared by a team of Service biologists, with the assistance of scientists from the U.S. Geological Survey's (USGS) Pacific Islands Ecosystems Research Center and the Service's Pacific Islands Climate Change Cooperative. We also obtained review and input from experts familiar with avian malaria and avian genetics. The species status report represents a compilation of the best scientific and commercial data available concerning the status of the species, including the past, present, and future threats to the iiwi. The final species status report, revised in response to peer reviewer comments, and other materials relating to this proposal can be found at http://www.regulations.gov, at Docket No. FWS-R1-ES-2016-0057, or by contacting the Pacific Islands Fish and Wildlife Office (see FOR FURTHER INFORMATION CONTACT).

Please refer to the proposed listing rule, published in the Federal Register on September 20, 2016 (81 FR 64414), for previous Federal actions for this species prior to that date. The publication of the proposed listing rule opened a 60-day public comment period that closed on November 21, 2016. We published a public notice of the proposed rule on September 19, 2016. This notice was picked up and published by several local media outlets including the State's largest newspaper, the Honolulu Star Advertiser, as well as the Garden Island Newspaper, Honolulu Civil Beat, and Hawaii News Now.

We solicited comments during the 60-day public comment period from September 20, to November 21, 2016 (81 FR 64414). We contacted appropriate Federal and State agencies, scientific experts and organizations, and other interested parties and invited them to comment on the proposal. Notices inviting public comment also were published in four major news outlets in the State. During the comment period, we received a total of nine letters from members of the public. We did not receive any requests for a public hearing. In this final rule, we address only those comments directly relevant to the listing of the iiwi. All nine letters were from individual members of the public. We did not receive any comments from the State of Hawaii.

Of the nine comment letters we received from members of the public, eight expressed general support for our listing the iiwi under the Act, and one commented on a topic unrelated to our proposed rule. None of these letters provided new, substantive information or comments requiring specific response here.

In accordance with our peer review policy published on July 1, 1994 (59 FR 34270), we solicited expert opinions from eight individuals with scientific expertise on the iiwi and its habitat, biological needs, and threats, including familiarity with the geographic region where the iiwi occurs, and principles of conservation biology. We received responses from all eight of these individuals.

In general, all of the peer reviewers agreed that the draft Species Status Report and proposed rule provided an accurate synthesis of the life history of the iiwi and robust analysis of the stressors affecting the species. They further agreed that our conclusions regarding the status of the species were reasonable and scientifically sound. We reviewed all comments received from the peer reviewers for substantive issues and new information regarding the listing of iiwi. Where appropriate, we have incorporated corrections, editorial suggestions, and new literature and other information they provided into both the final species report and final rule. Any substantive comments are discussed below (see also Summary of Changes from Proposed Rule). All of the peer reviews were constructive and thorough; we thank the peer reviewers for their thoughtful assistance.

Comment (1): Two of the peer reviews suggested that we had not sufficiently emphasized the potential importance of avian pox as a threat to the iiwi. Specifically, the reviewers noted that the literature on mosquito-borne diseases affecting native Hawaiian forest birds tends to be focused more on avian malaria due, in part, to the knowledge gaps about the impacts of avian pox and the lack of an accurate, noninvasive diagnostic test for identifying acute active infections and birds that have recovered from infection. The reviewers point out that the two diseases may be acting both individually and synergistically when infections are simultaneous. Although avian malaria has been more thoroughly studied, the peer reviewers felt that the available evidence suggests avian pox may also be a significant source of mortality and pose a greater threat to the iiwi than would be suggested by our analysis.

Our Response: Although our draft Species Status Report pointed to the difficulty in untangling the relationship between the two diseases because of their frequent occurrence together, we agree with the reviewers that we placed more emphasis on the threat posed by avian malaria, in part simply due to the greater amount of scientific information available that clearly links high levels of mortality in iiwi directly to infection with malaria. In our final Species Status Report and this final rule, we have increased emphasis on the possibility that avian pox, both alone and in combination with avian malaria, may have negative, population-level impacts on iiwi.

Comment (2): One reviewer suggested that the “estimate” of 50 birds on Oahu reported in the draft Species Status Report is unrealistically high and not based on scientific data; the reviewer stated that based on observations of occasional single birds over the past 15 years, the population is probably much less than 50, perhaps 10 at the most. Likewise for Molokai, the reviewer pointed out that the estimated number of birds from the 1980s is no longer accurate, and there are many fewer than 80 birds on that island.

Our Response: We thank the reviewer for his comments, and have made the corrections as needed in the final Species Status Report. Because the proposed rule did not refer to specific numbers of birds, no associated changes were required in this final rule.

Comment (3): Two peer reviewers provided updated information regarding the impacts and extent of various diseases affecting ohia trees, especially rapid ohia death (also known as ohia wilt, caused by fungi in the genus Ceratocystis).

Our Response: We have incorporated these changes into the final Species Status Report and final rule, as appropriate. In particular, we have updated the estimated area infected with rapid ohia death on Hawaii Island to more than 50,000 acres (20,235 hectares) (Hughes 2016, pers. comm.).

Comment (4): One peer reviewer pointed out that, although Paxton et al. (2013) stated that the iiwi population on the leeward (Kona) side of Hawaii Island is strongly increasing, they couched those specific results as the inference from a limited dataset. The reviewer suggested that it was important for us to provide a similar caveat with regard to this reported trend in our final Species Status Report and final rule.

Our Response: We agree that this point provides important context for the interpretation of this reported trend, and have provided additional language in the final Species Status Report and in this final rule to more accurately mirror the reported results of Paxton et al. 2013.

Comment (5): One peer reviewer suggested that, although it is true that the effects of predation have not been well documented or quantified for the iiwi, there is substantial evidence that predation by nonnative rats, particularly the black rat (Rattus rattus), is a serious threat to other Hawaiian forest birds. Although the reviewer acknowledges that predation is difficult to detect and document, particularly in species like the iiwi that nest high in the forest canopy, he believes the available evidence suggests predation by rats is likely also a contributing factor in the decline of the iiwi.

Our Response: We have incorporated additional discussion of the potential impacts of rat predation on the iiwi in this final rule.

Comment (6): Two peer reviewers suggested that we consider the findings of Paxton et al. (2016) in a paper published subsequent to the writing of our draft Species Status Report.

Our Response: We have incorporated the results of Paxton et al. 2016 into our final Species Status Report and this final rule. This research documents the rapid collapse of the native avian community on the island of Kauai since 2000 as a result of the impacts of mosquito-borne diseases exacerbated by increased ambient temperature. In particular, the projections of Paxton et al. (2016) point to the likely extirpation of the iiwi from the island of Kauai by the year 2050 as a consequence of the loss of disease-free habitat on Kauai and consequent exposure to avian malaria and pox. We also updated the reported numbers and range of iiwi on Kauai with the more recent estimates from Paxton et al. (2016).

After consideration of the comments we received during the public comment period and new information published or obtained since the proposed rule was published, we have made some changes to the final rule. None of these changes affect the determination. We made many small, nonsubstantive changes and corrections (e.g., updating the Background section in response to comments, minor clarifications, and editorial changes) throughout the document. In addition, we made some substantive changes to the information in this final rule in response to peer review, which are summarized here:

(1) We have elevated the identification of avian pox as a potentially important factor contributing to the decline of iiwi in response to mosquito-borne diseases, in addition to the effects of avian malaria;

(2) We have made a more definitive statement about the likely negative effects of rat predation on iiwi (VanderWerf 2016, pers. comm.);

(3) We updated the amount of area on Hawaii Island that is now estimated to be affected by rapid ohia death, which has now increased to more than 50,000 acres (20,235 hectares) (Hughes 2016, pers. comm.);

(4) We have updated our discussion of both the documented and projected declines of native forest birds on the island of Kauai to reflect the recently published work of Paxton et al. (2016), which projects the potential extirpation of iiwi from that island by the year 2050 as a consequence of warming temperatures and associated exposure to mosquito-borne diseases.

A thorough review of the taxonomy, life history, and ecology of the iiwi (Drepanis coccinea) is presented in the Iiwi (Drepanis coccinea) Species Status Report, available online at http://www.regulations.gov under Docket No. FWS-R1-ES-2016-0057. The species status report documents the results of our comprehensive biological status review for the iiwi, including an assessment of the potential stressors to the species. The species status report does not represent a decision by the Service on whether the iiwi should be listed as a threatened or endangered species under the Act; that decision involves the application of standards within the Act and its implementing regulations and policies. The species report does, however, provide the scientific basis that informs our regulatory decision. We have revised the report in response to comments from peer reviewers, who provided new information, additional references, and minor corrections. None of these changes substantively altered the conclusions we drew from the available information or changed the outcome of our assessment. The following is a summary of the key results and conclusions from the species status report.

A medium-sized forest bird notable for its iconic bright red feathers, black wings and tail, and a long, curved bill (Fancy and Ralph 1998, p. 2), the iiwi belongs to the family Fringillidae and the endemic Hawaiian honeycreeper subfamily, Drepanidinae (Pratt et al. 2009, pp. 114, 122). Iiwi songs are complex with variable creaks (often described as sounding like a “rusty hinge”), whistles, or gurgling sounds, and they sometimes mimic other birds (Fancy and Ralph 1998, p. 5; Hawaii Audubon Society 2011, p. 97). The species is found primarily in closed canopy, montane wet or montane mesic forests composed of tall stature ohia (Metrosideros polymorpha) trees or ohia and koa (Acacia koa) tree mixed forest. The iiwi's diet consists primarily of nectar from the flowers of ohia and mamane (Sophora chrysophylla), various plants in the lobelia (Campanulaceae) family (Pratt et al. 2009, p. 193), and occasionally, insects and spiders (Fancy and Ralph 1998, pp. 4-5; Pratt et al. 2009, p. 193).

Although iiwi may breed anytime between October and August (Fancy and Ralph 1998, p. 7-8), the main breeding season occurs between February and June, which coincides with peak flowering of ohia (Fancy and Ralph 1997, p. 2). Iiwi create cup-shaped nests typically within the upper canopy of ohia (Fancy and Ralph 1998, p. 7-8), and breeding pairs defend a small area around the nest and disperse after the breeding season (Fancy and Ralph 1997, p. 2). An iiwi clutch typically consists of two eggs, with a breeding pair raising one to two broods per year (Fancy and Ralph 1998, p. 7-8).

Well known for their seasonal movements in response to the availability of flowering ohia and mamane, iiwi are strong fliers that move long distances following their breeding season to locate nectar sources (Fancy and Ralph 1998, p. 3; Kuntz 2008, p. 1; Guillamet et al. 2016, p. 192). The iiwi's seasonal movement to lower elevation areas in search of nectar sources is an important factor in the exposure of the species to avian diseases, particularly malaria (discussed below).

Although historical abundance estimates are not available, the iiwi was considered one of the most common of the native forest birds in Hawaii by early naturalists, described as “ubiquitous” and found from sea level to the tree line across all the major islands (Banko 1981, pp. 1-2). Today the iiwi is no longer found on Lanai, and only a few individuals may be found on Oahu, Molokai, and west Maui. Remaining populations of iiwi are largely restricted to forests above approximately 3,937 feet (ft) (1,200 meters (m)) in elevation on Hawaii Island (Big Island), east Maui, and Kauai. As described below, the present distribution of iiwi corresponds with areas that are above the elevation at which the transmission of avian malaria readily occurs (“disease-free” habitats). The current abundance of iiwi rangewide is estimated at a mean of 605,418 individuals (range 550,972 to 659,864). Ninety percent of all iiwi now occur on Hawaii Island, followed by east Maui (about 10 percent), and Kauai (less than 1 percent) (Paxton et al. 2013, p. 10; Paxton et al. 2016, p. 2).

Iiwi population trends and abundance vary across the islands. The population on Kauai appears to be in steep decline, with a modeled rate of decrease equivalent to a 92 percent reduction in population over a 25-year period (Paxton et al. 2013, p. 10); the total population on Kauai is estimated at a mean of 2,603 birds (range 1,789 to 3,520) (Paxton et al. 2016, p. 2). Trends on Maui are mixed, but populations there generally appear to be in decline; East Maui supports an estimated population of 59,859 individuals (range 54,569 to 65,148) (Paxton et al. 2013, p. 10). On Hawaii Island, which supports the largest remaining numbers of iiwi at an estimated average of 543,009 individuals (range 516,312 to 569,706), evidence exists for stable or declining populations on the windward side of the island. Strong trends of increase are inferred on the leeward (Kona) side of the island, but these trends should be interpreted with caution because they are based on a limited number of surveys (Paxton et al. 2013, pp. 25-26; Camp 2016, pers. comm.). As noted above, iiwi have been extirpated from Lanai, and only a few individual birds have been sporadically detected on the islands of Oahu, Molokai, and on west Maui in recent decades. Of the nine iiwi population regions for which sufficient information is available for quantitative inference, five of those show strong or very strong evidence of declining populations; one, a stable to declining population; one, a stable to increasing population; and two, strong evidence for increasing populations. Four of the nine regions show evidence of range contraction. Overall, based on the most recent surveys (up to 2012), approximately 90 percent of remaining iiwi are restricted to forest within a narrow band between 4,265 and 6,234 ft (1,300 and 1,900 m) in elevation (Paxton et al. 2013, pp. 1, 10-11, and Figure 1) (See the Population Status section of the species status report for details).

The Act directs us to determine whether any species is an endangered species or a threatened species because of any of five various factors affecting its continued existence. Our species status report evaluated many potential stressors to iiwi, particularly direct impacts on the species from introduced diseases, as well as predation by introduced mammals, competition with nonnative birds, climate change, ectoparasites, and the effects of small population size. We also assessed stressors that may affect the extent or quality of the iiwi's required ohia forest habitat, including ohia dieback (a natural phenomenon), ohia rust (a nonnative pathogen), drought, fires, volcanic eruptions, climate change, and particularly rapid ohia death (ROD, also known as ohia wilt; a nonnative pathogen) and habitat alteration by nonnative plants and feral ungulates.

All species experience stressors; we consider a stressor to rise to the level of a threat to the species if the magnitude of the stressor is such that it places the current or future viability of the species at risk. In considering what stressors or factors might constitute threats to a species, we must look beyond the exposure of the species to a particular stressor to evaluate whether the species may respond to that stressor in a way that causes impacts to the species now or is likely to cause impacts in the future. If there is exposure to a stressor and the species responds negatively, the stressor may be a threat. We consider the stressor to be a threat if it drives, or contributes to, the risk of extinction of the species such that the species warrants listing as endangered or threatened as those terms are defined in the Act. However, the identification of stressors that could affect a species negatively may not be sufficient to compel a finding that the species warrants listing. The information must include evidence sufficient to suggest that these stressors are operative threats that act on the species to the point that the species may meet the definition of endangered or threatened under the Act.

Our species status report examines all of the potential stressors to iiwi in detail. Here we describe those stressors that we conclude rise to the level of a threat to the long-term viability of iiwi.

Based on our comprehensive assessment of the status of the iiwi, we conclude that the best scientific data available consistently identifies avian malaria as the primary driver of declines in abundance and distribution of iiwi observed since the turn of the 20th century. This conclusion is supported by the extremely high mortality rate of iiwi (approximately 95 percent) in response to avian malaria, and the disappearance of iiwi from low-elevation ohia forest where it was formerly common and where malaria is prevalent today. Both the life cycle of the mosquito vector and the development and transmission of the malaria parasite are temperature-limited; thus, iiwi are now found primarily in high-elevation forests above 3,937 ft (1,200 m) where malaria prevalence and transmission is only brief and episodic, or nonexistent, under current conditions. The honeycreepers amakihi and apapane appear to be developing some resistance or tolerance to avian malaria (e.g., Woodworth et al. 2005, p. 1,531; Atkinson et al. 2014, p. 366; Samuel et al. 2015, pp. 12-13). In contrast, iiwi have not demonstrated any substantial sign of developing resistance to avian malaria to date and do not appear to be genetically predisposed to evolve resistance (Jarvi et al. 2004, pp. 2,164-2,166). As the prevalence of avian malaria increases in association with warmer temperatures (e.g., LaPointe et al. 2012, p. 217), the extent and impact of avian diseases upon iiwi are projected to become greatly exacerbated by climate change during this century.

Additionally, on Hawaii Island, where 90 percent of the iiwi currently occur, the recently discovered tree disease, ohia wilt, commonly known in Hawaii as rapid ohia death (ROD), was identified as an emergent source of habitat loss and degradation that has the potential to exacerbate other stressors to ohia forest habitat, as well as reduce the amount of habitat remaining for iiwi in an already limited, disease-free zone contained within a narrow elevation band. Rapid ohia death leads to significant mortality of the ohia that iiwi depend upon for nesting and foraging. This disease is spreading rapidly and has become a matter of urgent concern. If ROD continues to spread across the native ohia forests, it will directly threaten iiwi by eliminating the limited, malaria-free native forest areas that remain for the species.

Based on the analysis in our species status report, invasive, nonnative plants and feral ungulates have major, adverse impacts on ohia forest habitat. Although we did not find that the historical and ongoing habitat alteration by nonnative species is the primary cause of the significant observed decline in iiwi's abundance and distribution, the cumulative impacts to iiwi's habitat, and in particular the activities of feral ungulates, are not insignificant and likely exacerbate the effects of avian malaria. Feral ungulates, particularly pigs (Sus scrofa), goats (Capra hircus), and axis deer (Axis axis), degrade ohia forest habitat by spreading nonnative plant seeds and grazing on and trampling native vegetation, and contributing to erosion (Mountainspring 1986, p. 95; Camp et al. 2010, p. 198). Invasive nonnative plants, such as strawberry guava (Psidium cattleianum) and albizia trees (Falcataria moluccana), prevent or retard regeneration of ohia forest used by iiwi for foraging and nesting. The combined effects of drought and nonnative, invasive grasses have resulted in increased fire frequency and the conversion of mesic ohia woodland to exotic grassland in many areas of Hawaii ((D'Antonio and Vitousek 1992, p. 67; Smith and Tunison 1992, pp. 395-397; Vitousek et al. 1997, pp. 7-8; D'Antonio et al. 2011, p. 1,617). Beyond alteration of ohia forest, feral pig activities that create mosquito habitat in ohia forest where there would otherwise be very little to none is identified as an important compounding stressor that acts synergistically with the prevalence of malaria and results in iiwi mortality. Although habitat loss and degradation is not, by itself, considered to be a primary driver of iiwi declines, the habitat impacts described above contribute cumulatively to the vulnerability of the species to the threat of avian malaria by degrading the quality and quantity of the remaining disease-free habitat upon which the iiwi depends. In this regard, ROD, discussed above, is a matter of urgent concern as it can further exacerbate and compound effects from the suite of stressors that impact iiwi (see below).

The introduction of avian diseases transmitted by the introduced southern house mosquito (Culex quinquefasciatus), including avian malaria (caused by the protozoan Plasmodium relictum) and avian pox (Avipoxvirus sp.), has been a key driving force in both extinctions and extensive declines over the last century in the abundance, diversity, and distribution of many Hawaiian forest bird species, including declines of the iiwi and other endemic honeycreepers (e.g., Warner 1968, entire; Van Riper et al. 1986, entire; Benning et al. 2002, p. 14,246; Atkinson and LaPointe 2009a, p. 243; Atkinson and LaPointe 2009b, pp. 55-56; Samuel et al. 2011, p. 2,970; LaPointe et al. 2012, p. 214; Samuel et al. 2015, pp. 13-15). Nonnative to Hawaii, the first species of mosquitoes were accidentally introduced to the Hawaiian Islands in 1826, and spread quickly to the lowlands of all the major islands (Warner 1968, p. 104; Van Riper et al. 1986, p. 340). Early observations of birds with characteristic lesions suggest that avian pox virus was established in Hawaii by the late 1800s (Warner 1968, p. 106; Atkinson and LaPointe 2009a, p. 55), and later genetic analyses indicate pox was present in the Hawaiian Islands by at least 1900 (Jarvi et al. 2008, p. 339). Avian malaria had arrived in Hawaii in the early 20th century (Warner 1968, p. 107; Van Riper et al. 1986, pp. 340-341; Atkinson and LaPointe 2009, p. 55; Banko and Banko 2009, p. 52), likely in association with imported cage birds (Yorinks and Atkinson 2000, p. 731), or through the deliberate introduction of nonnative birds to replace the native birds that had by then disappeared from the lowlands (Atkinson and LaPointe 2009a, p. 55).

As noted above, avian malaria is a disease caused by the protozoan parasite Plasmodium relictum; the parasite is transmitted by the mosquito Culex quinquefasciatus, and invades the red blood cells of birds. Birds suffering from malaria infection undergo an acute phase of the disease during which parasitemia, a quantitative measure of the number of Plasmodium parasites in the circulating red blood cells, increases steadily. Because the parasite destroys the red blood cells, anemia and decline of physical condition can quickly result. In native Hawaiian forest birds, death may result either directly from the effects of anemia, or indirectly when anemia-weakened birds become vulnerable to predation, starvation, or a combination of other stressors (LaPointe et al. 2012, p. 213). Native Hawaiian birds that survive avian malaria remain chronically infected, thus becoming lifetime reservoirs of the disease (Samuel et al. 2011, p. 2,960; LaPointe et al. 2012, p. 216) and remaining capable of further disease transmission to other native birds. In contrast, nonnative birds in Hawaii are little affected by avian malaria and later become incapable of disease transmission (LaPointe et al. 2012, p. 216).

Wild iiwi infected with malaria are rarely captured, apparently because the onset of infection leads to rapid mortality, precluding their capture (Samuel et al. 2011, p. 2,967; LaPointe et al. 2016, p. 11). However, controlled experiments with captive birds have demonstrated the susceptibility of native Hawaiian honeycreepers to avian malaria; mortality is extremely high in some species, including iiwi, experimentally infected with the disease. As early as the 1960s, experiments with Laysan finches (Telespiza cantans) and several other species of native Hawaiian honeycreepers demonstrated 100 percent mortality from malaria in a very short period of time (Warner 1968, pp. 109-112, 118; Fig. 426).

In a study specific to iiwi, Atkinson et al. (1995, entire) demonstrated that the species suffers approximately 95 percent mortality when infected with malaria (Atkinson et al. 1995, p. S65). All of the exposed iiwi developed infections within 4 days, with only a single male iiwi surviving. Following re-exposure with the same Plasmodium isolate after initial infection, no subsequent increase in parasitemia was detected, suggesting a possible development of some immunity (Atkinson et al. 1995, p. S66). The authors suggested that iiwi may lack sufficient diversity in the major histocompatibility complex or genetically based immunity traits capable of recognizing and responding to malarial antigens, an important factor in iiwi's susceptibility to introduced disease (Atkinson et al. 1995, pp. S65-S66).

Despite extremely high mortality of iiwi from avian malaria in general, the aforementioned study as well as two other studies have demonstrated that a few individuals have survived infection (Van Riper et al. 1986, p. 334; Atkinson et al. 1995, p. S63; Freed et al. 2005, p. 759). If a genetic correlation were identified, it is possible that surviving individuals could serve as a potential source for the evolution of genetic resistance to malaria, although evidence of this is scant to date. Eggert et al. (2008, p. 8) reported a slight but detectable level of genetic differentiation between iiwi populations located at mid and high elevation, potentially the first sign of selection acting on these populations in response to disease. Additionally, the infrequent but occasional sighting of iiwi on Oahu indicates a possible developed resistance or tolerance to avian malaria. Moreover, other more common honeycreepers, such as the amakihi and apapane, show signs of developing resistance or tolerance to the disease, as evidenced by molecular studies (e.g., Woodworth et al. 2005, p. 1,531; Atkinson et al. 2014, p. 366) and their continued distribution at mid and low elevations where mosquitos and malaria transmission persist year-round (e.g., Foster et al. 2004, entire; Eggert et al. 2008, pp. 7-8).

Despite these observations, there is no indication as of yet that iiwi have developed significant resistance to malaria such that individuals can survive in areas where the disease is strongly prevalent, including all potential low-elevation forest habitat and most mid-elevation forest habitat (Foster et al. 2007, p. 4,743; Eggert et al. 2008, p. 2). In one study, for example, 4 years of mist-netting effort across extensive areas of Hawaii Island resulted in the capture of a substantial number of iiwi, yet no iiwi were captured in low-elevation forests and only a few were captured in mid-elevation forests (Samuel et al. 2015, p. 11). In addition, several studies indicate that iiwi have low genetic variability, and even genetic impediments to a possible evolved resistance to malaria in the future (Jarvi et al. 2001, p. 255; Jarvi et al. 2004, Table 4, p. 2,164; Foster et al. 2007, p. 4,744; Samuel et al. 2015, pp. 12-13). For example, Eggert et al. (2008, p. 9) noted that gene variations that may confer resistance appear to be rare in iiwi.

Three factors—the homogeneity of a portion of the iiwi genome, the high mortality rate of iiwi in response to avian malaria, and high levels of gene flow resulting from the wide-ranging nature of the species—suggest that iiwi would likely require a significant amount of time for development of genetic resistance to avian malaria, assuming the species retains a sufficiently large reservoir of genetic diversity for a response to natural selection. Genetic studies of iiwi have also noted a dichotomy between the lack of variation in mitochondrial DNA (Tarr and Fleischer 1993, 1995; Fleischer et al. 1998; Foster et al. 2007, p. 4,743), and maintenance of variation in nuclear DNA (Jarvi et al. 2004, p. 2,166; Foster et al. 2007, p. 4,744); both attributes suggest that iiwi may have historically experienced a drastic reduction in population size that led to a genetic bottleneck. Studies have also found low diversity in the antigen-binding sites of the iiwi's major histocompatibility complex (that part of an organism's immune system that helps to recognize foreign or incompatible proteins (antigens) and trigger an immune response).

The relationship between temperature and avian malaria is of extreme importance to the current persistence of iiwi and the viability of the species in the future. The development of the Plasmodium parasite that carries malaria responds positively to increased temperature, such that malaria transmission is greatest in warm, low-elevation forests with an average temperature of 72 °F (22 °C), and is largely absent in high-elevation forests above 4,921 ft (1,500 m) with cooler mean annual temperatures around 57 °F (14 °C) (Ahumada et al. 2004, p. 1,167; LaPointe et al. 2010, p. 318; Liao et al. 2015, p. 4,343). High-elevation forests thus currently serve as disease-free habitat zones for Hawaiian forest birds, including iiwi. Once one of the most common birds in forests throughout the Hawaiian islands, iiwi are now rarely found at lower elevations, and are increasingly restricted to high-elevation mesic and wet forests where cooler temperatures limit both the development of the malarial parasite and mosquito densities (Scott et al. 1986, pp. 367-368; Ahumada et al. 2004, p. 1,167; LaPointe et al. 2010, p. 318; Samuel et al. 2011, p. 2,960; Liao et al. 2015, p. 4,346; Samuel et al. 2015, p. 14).

Temperature also affects the life cycle of the malaria mosquito vector, Culex quinquefasciatus. Lower temperatures slow the development of larval stages and can affect the survival of adults (Ahumada et al. 2005, pp. 1,165-1,168; LaPointe et al. 2012, p. 217). Although closely tied to altitude and a corresponding decrease in temperature, the actual range of mosquitoes varies with season. Generally, as temperature decreases with increasing elevation, mosquito abundance drops significantly at higher altitudes. In the Hawaiian Islands, the mosquito boundary occurs between 4,921 and 5,577 ft (1,500 and 1,700 m) (VanRiper et al. 1986, p. 338; LaPointe et al. 2012, p. 218). Areas above this elevation are at least seasonally relatively free of mosquitoes; thus, malaria transmission is unlikely at these high elevations under current conditions.

Early on, Ralph and Fancy (1995, p. 741) and Atkinson et al. (1995, p. S66) suggested that the seasonal movements of iiwi to lower elevation areas where ohia is flowering may result in increased contact with malaria-infected mosquitoes, which, combined with the iiwi's high susceptibility to the disease, may explain their observed low annual survivorship relative to other native Hawaiian birds. Compounding the issue, other bird species that overlap with iiwi in habitat, including Apapane (Himatione sanguinea), are relatively resistant to the diseases and carry both Plasmodium and avian pox virus. As reservoirs, they carry these diseases upslope where mosquitoes are less abundant but still occur in numbers sufficient to facilitate and continue transmission to iiwi (Ralph and Fancy 1995, p. 741).

Subsequent studies have confirmed the correlation between risk of malaria infection and iiwi altitudinal migrations, and suggest upper elevation forest reserves in Hawaii may not adequately protect mobile nectarivores such as iiwi. Kuntz (2008, p. 3) found iiwi populations at upper elevation study sites (6,300 ft (1,920 m)) declined during the non-breeding season when birds departed for lower elevations in search of flowering ohia, traveling up to 12 mi (19.4 km) over contiguous mosquito-infested wet forest. Guillamet et al. (2016, p. 192) used empirical measures of seasonal movement patterns in iiwi to model how movement across elevations increases the risk of disease exposure, even affecting breeding populations in disease-free areas. La Pointe et al. (unpublished data 2015) found that, based on malaria prevalence in all Hawaiian forest birds, species migrating between upper elevations to lower elevations increased their risk of exposure to avian malaria by as much as 27 times. The greater risk was shown to be due to a much higher abundance of mosquitoes at lower elevations, which in turn was attributable at least in part to the higher abundance of pigs and their activities in lower elevation forests (discussed further below).

Avian pox (or bird pox) is an infection caused by the virus Avipoxvirus, which produces large, granular, and eventually dead tissue lesions or tumors on exposed skin or infected lesions on the mouth, trachea, and esophagus of infected birds. Avian pox can be transmitted through cuts or wounds upon physical contact or through the mouth parts of blood-sucking insects such as the mosquito Culex quinquefasciatus, the common vector for both the pox virus and avian malaria (LaPointe et al. 2012, p. 221). Tumors or lesions caused by avian pox can be crippling for birds, and may result in death. Although not extensively studied, existing data suggest that mortality from avian pox may range from 4 to 10 percent observed in Oahu Elepaio (Chasiempis ibidis) (for birds with active lesions) (VanderWerf 2009, p. 743) to 100 percent in Laysan finches (Warner 1968, p. 108). VanderWerf (2009, p. 743) has also suggested that mortality levels from pox may correlate with higher rainfall years, and at least in the case of the Elepaio, observed mortality may decrease over time with a reduction in susceptible birds.

As early as 1902, native birds suffering from avian pox were observed in the Hawaiian Islands, and Warner (1968, p. 106) described reports that epizootics of avian pox “were so numerous and extreme that large numbers of diseased and badly debilitated birds could be observed in the field.” As the initial wave of post-European extinctions of native Hawaiian birds was largely observed in the late 1800s, prior to the introduction of avian malaria (Van Riper et al. 1986, p. 342), it is possible that avian pox played a significant role, although there is no direct evidence (Warner 1968, p. 106). Molecular work has revealed two genetically distinct variants of the pox virus affecting forest birds in Hawaii that differ in virulence (Jarvi et al. 2008, p. 347): One tends to produce fatal lesions, and the other appears to be less severe, based on the observation of recurring pox infections in birds with healed lesions (Atkinson et al. 2009, p. 56).

The largest study of avian pox in scope and scale took place between 1977 and 1980, during which approximately 15,000 native and nonnative forest birds were captured and examined for pox virus lesions on Hawaii Island (Van Riper et al. 2002, pp. 929-942). The study made several important determinations, including that native forest birds were indeed more susceptible than introduced species, that all species were more likely to be infected during the wet season, and that pox prevalence was greatest at mid-elevation sites approximately 3,937 ft (1,200 m) in elevation, coinciding with the greatest overlap between birds and the mosquito vector. Of the 107 iiwi captured and examined during the study, 17 percent showed signs of either active or inactive pox lesions (Van Riper et al. 2002, p. 932). Many studies of avian pox have documented that native birds are frequently infected with both avian pox and avian malaria (Van Riper et al. 1986, p. 331; Atkinson et al. 2005, p. 537; Jarvi et al. 2008, p. 347). This may be due to mosquito transmission of both pathogens simultaneously, because documented immune system suppression by the pox virus renders chronically infected birds more vulnerable to infection by, or a relapse of, malaria (Jarvi et al. 2008, p. 347), or due to other unknown factors. The relative frequency with which the two diseases co-occur makes it challenging to disentangle the independent impact of either stressor acting alone (LaPointe et al. 2012, p. 221). Although we lack direct evidence of the degree to which pox may be a specific threat to iiwi or contributing to its decline, both field observations of and limited experimental studies on closely related species of honeycreepers suggests that it may be a significant factor (Warner 1968, pp. 106, 108-109; VanRiper et al. 2002, pp. 936-939).

It has been widely established that damage to native tree ferns (Cibotium spp.) and rooting and wallowing activity by feral pigs create mosquito larval breeding sites in Hawaiian forests where they would not otherwise occur. The porous geology and relative absence of puddles, ponds, and slow-moving streams in most Hawaiian landscapes precludes an abundance of water-holding habitat sites for mosquito larvae; however, Culex quinquefasciatus mosquitoes, the sole vector for avian malaria in Hawaii, now occur in great density in many wet forests where their larvae primarily rely on habitats created by pig activity (LaPointe 2006, pp. 1-3; Ahumada et al. 2009, p. 354; Atkinson and LaPointe 2009, p. 60; Samuel et al. 2011, p. 2,971). Pigs compact volcanic soils and create wallows and water containers within downed, hollowed-out tree ferns, knocked over and consumed for their starchy pith (Scott et al. 1986, pp. 365-368; Atkinson et al. 1995, p. S68). The abundance of C. quinquefasciatus mosquitoes is also much greater in suburban and agricultural areas than in undisturbed native forest, and the mosquito is capable of dispersing up to 1 mile (1.6 kilometers) within closed-canopy native forest, including habitat occupied by the iiwi (LaPointe 2006, p. 3; LaPointe et al. 2009, p. 409).

In studies of native forest plots where feral ungulates (including pigs) were removed by trapping and other methods, researchers have demonstrated a correlation in the abundance of Culex spp. mosquitoes when comparing pig-free, fenced areas to adjacent sites where feral pig activity is unmanaged. Aruch et al. 2007 (p. 574), LaPointe 2006 (pp. 1-3) and LaPointe et al. (2009, p. 409; 2012, pp. 215, 219) assert that management of feral pigs may be strategic to managing avian malaria and pox, particularly in remote Hawaiian rain forests where studies have documented that habitats created by pigs are the most abundant and productive habitat for larval mosquitoes. Reduction in mosquito habitat must involve pig management across large landscapes due to the tremendous dispersal ability of C. quinquefasciatus and the possibility of the species invading from adjacent areas lacking management (LaPointe 2006, pp. 3-4). The consequences of feral pig activities thus further exacerbate the impacts to iiwi from avian malaria and avian pox, by creating and enhancing larval habitats for the mosquito vector, thereby increasing exposure to these diseases.

The relatively recent introduction of avian pox and avian malaria, in concert with the introduction of the mosquito disease vector, is widely viewed as one of the key factors underlying the loss and decline of native forest birds throughout the Hawaiian Islands. Evolving in the absence of mosquitoes and their vectored pathogens, native Hawaiian forest birds, particularly honeycreepers such as iiwi, lack natural immunity or genetic resistance, and thus are more susceptible to these diseases than are nonnative bird species (van Riper et al. 1986, pp. 327-328; Yorinks and Atkinson 2000, p. 737). Researchers consider iiwi one of the most vulnerable species, with an average of 95 percent mortality in response to infection with avian malaria (Atkinson et al. 1995, p. S63; Samuel et al. 2015, p. 2).

Many native forest birds, including iiwi, are now absent from warm, low-elevation areas that support large populations of disease-carrying mosquitoes, and these birds persist only in relatively disease-free zones in high-elevation forests, above roughly 4,921 to 5,577 ft (1,500 to 1,700 m), where both the development of the malarial parasite and the density of mosquito populations are held in check by cooler temperatures (Scott et al. 1986, pp. 85, 100, 365-368; Woodworth et al. 2009, p. 1,531; Liao et al. 2015, pp. 4,342-4,343; Samuel et al. 2015, pp. 11-12). Even at these elevations, however, disease transmission may occur when iiwi move downslope to forage on ephemeral patches of flowering ohia in the nonbreeding season, encountering disease-carrying mosquitoes in the process (Ralph and Fancy 1995, p. 741; Fancy and Ralph 1998, p. 3; Guillaumet et al. 2015, p. EV-8; LaPointe et al. 2015, p. 1). Iiwi have not demonstrably developed resistance to avian malaria, unlike related honeycreepers including Amakihi (Hemignathus spp.) and Apapane. Due to the extreme mortality rate of iiwi when exposed to avian malaria, we consider avian malaria in particular to pose a threat to iiwi. Having already experienced local extinctions and widespread population declines, it is possible that the species may not possess sufficient genetic diversity to adapt to these diseases (Atkinson et al. 2009, p. 58).

Based on the assessment of the best scientific data available, we conclude that climate change exacerbates the impacts to iiwi from mosquito-borne disease, and this effect is likely to continue and worsen in the future. Air temperature in Hawaii has increased in the past century and particularly since the 1970s, with the greatest increases at higher elevations, and several conservative climate change models project continued warming in Hawaii into the future. As a result, the temperature barrier to the development and transmission of avian malaria will continue to move up in elevation in response to warmer conditions, leading to the curtailment or loss of disease-free habitats for iiwi. We briefly discuss below three climate studies that conservatively predict the iiwi will lose between 60 and 90 percent of its current (and already limited) disease-free range by the end of this century, with significant effects occurring by mid-century.

Climate change is a stressor that is likely to significantly exacerbate the effects of avian malaria on iiwi both directly through increased prevalence and mortality, and indirectly through the loss of disease-free habitat. Air temperature in Hawaii has increased in the past century and particularly since the 1970s, with greater increases at high elevation (Giambelluca et al. 2008, pp. 2-4; Wang et al. 2014, pp. 95, 97). Documented impacts of increased temperature include the prevalence of avian malaria in forest birds at increasing elevation, including high-elevation sites where iiwi are already declining, for example, on Kauai (Paxton et al. 2013, p. 13; Paxton et al. 2016, entire). Several projections for future climate in Hawaii describe a continued warming trend, especially at high elevations. In our species status report, we analyzed in particular three climate studies (summarized below) that address the future of native forest birds, including iiwi, in the face of the interactions between climate change and avian malaria.

Benning et al. (2002) concluded that under optimistic assumptions (i.e., 3.6 °F (2 °C) increase in temperature by the year 2100), malaria-susceptible Hawaiian forest birds, including iiwi, will lose most of their disease-free habitat in the three sites they considered in their projection of climate change impacts. For example, current disease-free habitat at high elevation within the Hakalau Forest National Wildlife Refuge (NWR) on the island of Hawaii (where the environment is still too cold for development of the malarial parasite) would be reduced by 96 percent by the end of the century.

Fortini et al. (2015) conducted a vulnerability assessment for 20 species of Hawaiian forest birds based on a projected increase of 6.1 °F (3.4 °C) under the A1B emissions scenario at higher elevations by 2100. Even under this relatively optimistic scenario, in which emissions decline after mid-century (IPCC 2007, p. 44), all species were projected to suffer range loss as the result of increased transmission of avian malaria at higher elevations with increasing temperature. Iiwi was predicted to lose 60 percent of its current range by the year 2100, and climate conditions suitable for the species will shift up in elevation, including into areas that are not currently forested, such as lava flows and high-elevation grasslands. Most of the remaining habitat for iiwi would be restricted to a single island, Hawaii Island.

Liao et al. (2015) generated temperature and precipitation projections under three alternative emissions scenarios and projected future malaria risk for Hawaiian forest birds. Irrespective of the scenario modeled, by mid-century (roughly 2040), malaria transmission rates and impacts to bird populations began increasing at high elevations. By 2100, the increased annual malaria transmission rate for iiwi was projected to result in population declines of 70 to 90 percent for the species, depending on the emissions scenario.

All three of these studies consistently predict a significant loss of disease-free habitat for iiwi with consequent severe reductions in population size and distribution by the year 2100, with significant changes likely to be observed as early as 2040. As the iiwi's numbers and distribution continue to decline, the remaining small, isolated populations become increasingly vulnerable to loss of ohia forest habitat from other stressors such as ROD, as well as other environmental catastrophes and demographic stochasticity, particularly should all remaining iiwi become restricted to a single island (Hawaii Island), as some scenarios suggest.

Climate change will likely exacerbate other stressors to iiwi in addition to disease. Projected increases in temperature and humidity are likely to increase the spatial extent of areas on Hawaii Island vulnerable to ROD (Keith 2016, pers. comm). Changes in the amount and distribution of rainfall in Hawaii likely will affect the quality and extent of mesic and wet forests on which iiwi depend. Hawaii has experienced an overall drying trend since the 1920s, with an average annual decline in precipitation of 1.78 percent (Frazier and Giambelluca 2016, p. 4), but some future projections suggest that areas that currently are wet (windward sides of islands) will experience greater rainfall and more extreme rainfall events, while currently dry areas (leeward sides and high elevations) will become drier (Zhang et al. 2016, pp. 8,350-8,351). Changes in the trade wind inversion (which strongly influences rainfall) and other aspects of precipitation with climate change are difficult to model with confidence, complicating projections of future precipitation in Hawaii on various spatial scales (Chu and Chen 2005, pp. 4,801-4,802; Cao et al. 2007, pp. 1,158-1,159; Timm et al. 2015, p. 107; Fortini et al. 2015, p. 5; Liao et al. 2015, p. 4,345). In addition, potential increases in storm frequency and intensity in Hawaii as a result of climate change may lead to an increase in direct mortality of individual iiwi and a decline in the species' reproductive success. Currently, no well-developed projections exist for these possible cumulative effects.

The natural susceptibility of native forest birds to introduced diseases, in combination with the observed restriction of Hawaiian honeycreepers to high-elevation forests, led Atkinson et al. (1995, p. S68) to predict two decades ago that a shift in the current mosquito distribution to higher elevations could be “disastrous for those species with already reduced populations.” Thus, climate change has significant implications for the future of Hawaiian forest birds, as predictions suggest increased temperatures may largely eliminate the high-elevation forest currently inhospitable to the transmission of mosquito-borne diseases (Benning et al. 2002, pp. 14,247-14,249; LaPointe et al. 2012, p. 219; Fortini et al. 2015, p. 9). Samuel et al. (2015, p. 15) predict further reductions and extinctions of native Hawaiian birds as a consequence, noting that the iiwi is particularly vulnerable due to its high susceptibility to malaria. Finally, Paxton et al. (2016, entire) report a steepening decline in iiwi and other honeycreepers on Kauai since 2000.

Iiwi is projected to be extirpated from Kauai by 2050 as a result of the island having now passed a “tipping point” where increasing temperature exposes birds to mosquito-borne disease throughout their remaining range on the island; if the current trends of decline in distribution and abundance continue in a linear fashion in the future, iiwi could be extirpated from Kauai much sooner (Paxton et al. 2016, pp. 3, 5). The maximum elevation of forest habitat on Kauai (about 4,900 ft (1,500 m)) is less than that on either Maui or Hawaii Island, where similar trends of increase in temperature and the elevation of disease transmission are well documented, as discussed above. Iiwi, and other disease-susceptible honeycreepers, only persist in abundance on these higher islands in high-elevation, disease-free habitat that is shrinking with increasing temperature. In sum, several independent studies project consistently significant negative impacts to the iiwi as a result of climate change and the increased exposure to avian malaria as disease-free habitats shrink. As iiwi are known to exhibit 95 percent mortality on average as a result of avian malaria, the current numbers of iiwi are of little consequence should all or most of the remaining individuals become exposed to the disease in the future.

Rapid ohia death, a new disease that kills ohia trees, is a factor with the potential to exacerbate the threats currently affecting iiwi and reduce the amount of disease-free habitat remaining by destroying high-elevation ohia forest. Unexplained, widespread mortality of ohia trees was first detected in 2012 in lowland forests of the Puna Region of Hawaii Island (Keith et al. 2015, entire). Pathogenicity tests conducted by the USDA Agriculture Research Service determined that the vascular wilt disease, now commonly known in Hawaii as rapid ohia death (ROD), is caused by the fungus Ceratocystis fimbriata (Keith et al. 2015, pp. 1-2). A second, new species of Ceratocystis also kills ohia; this new species is being described as of this writing (Hughes 2016, pers. comm.; Keith 2016, pers. comm.).

Ohia stands experience rapid and extensive mortality from ROD. In 2014, approximately 15,000 ac (6,000 ha) of ohia forest from Kalapana to Hilo on Hawaii Island experienced greater than 50 percent mortality, with 100 percent mortality in some stands over a two to three year period (Friday et al. 2015, p. 1). Between 2014 and 2015, annual mortality rates measured in monitoring plots averaged from 24 percent (measured as ohia stems) to 28 percent (measured as ohia basal area) (Mortenson et al. 2016, p. 89). When these plots were established in the ROD-infected area in January and February of 2014, all had already experienced an average of approximately 39 percent ohia mortality (Mortenson et al. 2016, p. 89).

At present, the disease remains restricted to Hawaii Island, where it is spreading rapidly. In 2016, the amount of forest area affected on Hawaii Island was estimated to be more than 50,000 ac (20,235 ha), and this estimate includes a new outbreak in Laupahoehoe Forest Reserve on the Hamakua Coast (Hughes 2016, pers. comm.). The largest affected area is within the Puna District, where infected trees have been observed within approximately 4,000 discontinuous acres (1,619 ha) (Hughes 2016, pers. comm.). In some areas, dead and dying trees affected by the fungus have been observed within the range of iiwi (Hughes 2016, pers. comm.; Keith 2016, pers. comm.). Affected trees are found at elevations ranging from sea level up to approximately 5,000 ft (1,524 m), including at Wailuku Forest near Hakalau Forest NWR (Hughes 2016, pers. comm.), which contains a stable to increasing iiwi population (Paxton et al. 2013, p. 12). Hawaii Island is home to 90 percent of the current iiwi population, and this island will remain particularly important for the species: Iiwi are predicted to be largely if not entirely restricted to that island under some future climate change projections (Fortini et al. 2015, p. 9, Supplement 6).

Our species status report evaluated several regulatory and other measures in place today that might address or are otherwise intended to ameliorate the stressors to iiwi. Our analysis concluded that forest habitat protection, conservation, and restoration has the potential to benefit iiwi by protecting and enhancing breeding and foraging areas for the species while simultaneously reducing the abundance of mosquito breeding sites, despite the disease vector's (Culex quinquefasciatus) 1-mi (1.6-km) dispersal ability (LaPointe et al. 2009, pp. 408; 411-412; LaPointe et al. 2012, p. 215).

Because of the iiwi's extreme susceptibility to avian malaria, habitat to sustain the species must be disease-free. Efforts to restore and manage large, contiguous tracts of native forests have been shown to benefit iiwi, especially when combined with fencing and ungulate removal (LaPointe et al. 2009, p. 412; LaPointe et al. 2012, p. 219). While forest restoration and ungulate management at the Hakalau Forest NWR on Hawaii Island are excellent examples of what is needed to increase iiwi abundance, many similar large-scale projects would be necessary rangewide to simply reduce mosquito abundance and protect the species from current habitat threats alone. However, even wide-scale landscape habitat management would be unable to fully address the present scope of the threat of disease, and sufficient high-elevation forest is not available to provide disease-free habitat for iiwi in the face of future climate change. Even if disease-free habitat within managed areas could be restored and protected now, much of this habitat will lose its disease-free status as avian malaria moves upward in elevation in response to warming temperatures, as is occurring already within the Alakai Wilderness on the island of Kauai.

New opportunities are emerging, such as large-scale vector control using new tools that have the potential to assist Hawaiian forest birds (LaPointe et al. 2009, pp. 416-417; Reeves et al. 2014, p. e97557; Gantz et al. 2015, pp. E6736-E6743; Fischer in press, pp. 1-2). The most promising of these new tools forego chemicals as a means of lethal control and directly manipulate the viability (or fitness) of the mosquitoes and can be grouped into two broad categories: the Sterile Insect Technique (SIT) and the Population Replacement Technique (PRT) (Fischer in press, pp. 1-2). These tools have positive attributes that set them apart from traditional mosquito control options. These new approaches have the potential to achieve landscape-scale control, are species specific, and are more effective against dispersed, cryptic, and hard to-reach targets such as the Culex mosquitoes that carry avian malaria in Hawaiian forests (Alphey et al. 2010, pp. 297-299). Although these new developments are encouraging, these new technologies for achieving large-scale control or eradication of mosquitoes in Hawaii are still in the research and planning stage and have yet to be implemented or proven effective.

We also evaluated several regulations and agreements pertaining to climate change. Although the United States and some other countries have passed some regulations specifically intended to reduce the emission of greenhouse gases that contribute to climate change, the scope and effect of such regulations are limited. Indeed, during the United Nations Framework Convention on Climate Change (UNFCCC) meeting in December 2015, the UNFCCC indicated that, even if all the member countries' intended contributions to greenhouse gas reductions were fully implemented and targets met, the goal of limiting the increase in global average temperature to 2 °C (3.6 °F) by the year 2100 would not be achieved.

Many of the efforts to tackle the primary stressors to iiwi are still in the research and development stage, or are implemented only on a small or limited scale. Because the primary stressor, avian malaria, continues to have negative impacts, and these impacts are exacerbated by climate change, we conclude that the existing regulatory mechanisms do not offset these impacts to the species.

We have reviewed the best scientific and commercial data available regarding iiwi populations and the stressors that affect the species. This information includes, notably, a recent comprehensive analysis of iiwi abundance, distribution, and population trends (Paxton et al. 2013); numerous studies that provide information on the particularly high mortality of iiwi in response to avian malaria; and recent models examining the current relationship between climate and malaria, as well as the likely future consequences of climate change for iiwi and other Hawaiian forest birds (including Benning et al. 2002, Fortini et al. 2013, and Liao et al. 2015). Our review also reflects the expert opinion of the species' status report team members, and input provided by specialists familiar with avian malaria and iiwi genetics. We direct the reader to the iiwi species status report for our detailed evaluation of the biological status of the iiwi and the influences that may affect its continued existence.

Once one of the most common of the native Hawaiian forest birds, the iiwi has declined across large portions of its range and has been extirpated or nearly so from some islands, and many of the few remaining populations are declining. The iiwi's range is contracting upslope in most areas, and population declines and range contraction are concurrent with increasing prevalence of avian malaria. The iiwi is highly susceptible to avian malaria, and that the prevalence of this disease is moving upslope in Hawaiian forests correlated with temperature increases associated with climate change. This disease and its trend of increasing prevalence at increasing elevation are the chief drivers of observed iiwi population declines and range contraction. Although habitat management to reduce breeding habitat for mosquitoes may have slowed the decline of iiwi and other forest birds to some degree in a few locations, no landscape-scale plans or strategies exist for eradicating mosquitoes or otherwise reducing the risk posed by avian malaria to iiwi and other susceptible Hawaiian bird species.

The documented trend of temperature increase, which is greatest at high elevation, is projected to continue at least through the 21st century. The transmission of avian malaria is currently limited or absent at higher elevations, where temperatures are too cool for the development of the malaria parasite. However, multiple independent modeling efforts consistently project that the prevalence of avian malaria will continue to increase upslope with increasing temperature, eventually eliminating most or all remaining disease-free habitat in the islands. These models, which incorporate data on the distribution of forest birds and on disease transmission, project moderate to high avian malaria transmission at the highest elevations of the iiwi's current range by the end of this century, with some significant effects predicted within the next few decades. As a consequence, significant declines in iiwi populations are projected, on the order of 70 to 90 percent by 2100, depending on the future climate scenario.

The impacts of other stressors to iiwi, such as loss or degradation of native forest by nonnative species (disturbance or destruction by feral ungulates; invasion by nonnative plants; impacts from nonnative pathogens such as ROD), predation by mongooses and feral cats, and small-population stressors such as demographic stochasticity and loss of genetic diversity, have not been well documented or quantified (predation by rats, notably Rattus rattus, is suspected to contribute to decline in iiwi) (VanderWerf 2016, pers. comm.). However, any stressors that result in further degradation or fragmentation of the forests on which the iiwi relies for foraging and nesting, or result in increased mortality or reduced reproductive success, are likely to exacerbate the impacts of disease on the species. The effects of climate change are likely to exacerbate these other stressors to iiwi as well.

As the number and distribution of iiwi continue to decline, the remaining small, isolated populations become increasingly vulnerable to environmental catastrophes and demographic stochasticity; this will particularly be the case should all remaining iiwi become restricted to Hawaii Island, as some modeling scenarios suggest. Ninety percent of the rangewide iiwi population is already restricted to Hawaii Island, where ROD has recently emerged as a fast-moving threat to the already limited ohia forest habitat required by iiwi.

In consideration of all of this information, we conclude that avian malaria and possibly avian pox, as exacerbated by the ongoing effects of climate change, pose a threat to iiwi, and the action of these stressors places the species as a whole at an elevated risk of extinction. Because the vast majority of the remaining iiwi population is restricted to the island of Hawaii, we consider ROD to pose a threat to the future viability of iiwi as well, as it may result in major loss of forest within the iiwi's remaining range on that island.

Section 4 of the Act (16 U.S.C. 1533), and its implementing regulations in title 50 of the Code of Federal Regulations at 50 CFR part 424, set forth the procedures for adding species to the Federal Lists of Endangered and Threatened Wildlife and Plants. Under section 4(a)(1) of the Act, we may list a species based on (A) The present or threatened destruction, modification, or curtailment of its habitat or range; (B) Overutilization for commercial, recreational, scientific, or educational purposes; (C) Disease or predation; (D) The inadequacy of existing regulatory mechanisms; or (E) Other natural or manmade factors affecting its continued existence. Listing actions may be warranted based on any of the above threat factors, singly or in combination.

We have carefully assessed the best scientific and commercial information available regarding the past, present, and future threats to the iiwi. As described in the species status report, in considering the five listing factors, we evaluated many potential stressors to iiwi, including but not limited to: Stressors that may affect the extent or quality of the bird's ohia forest habitat (ROD and ohia rust (both nonnative pathogens), ohia dieback (a natural phenomenon), drought, fires, volcanic eruptions, nonnative plants, and feral ungulates), introduced diseases, predation by introduced mammals, competition with nonnative birds, ectoparasites, climate change, and the effects of small population size. Based on our assessment, disease—particularly avian malaria—is the primary driver in the ongoing declines in abundance and range of iiwi, and climate change substantially exacerbates the impact of disease on the species and will continue to do so into the future.

The greatest current threat to iiwi comes from exposure to introduced diseases carried by nonnative mosquitoes (Factor C). Avian malaria in particular has been clearly demonstrated to result in extremely high mortality of iiwi; avian pox may have significant effects on iiwi as well, although the evidence is not as clear or measurable. These diseases have resulted in significant losses of the once ubiquitous iiwi, which remains highly susceptible and, as of present, shows no clear indication of having developed substantial resistance or tolerance. Exposure to these diseases is ongoing, and is expected to increase as a consequence of the effects of climate change (Factor E).

Several climate model projections predict that continued increases in temperature due to climate change will greatly exacerbate the impacts of avian diseases upon iiwi due to loss of disease-free habitat. Several iiwi populations, including those on Molokai, Kauai, West Maui, and possibly Oahu—all lower in elevation than East Maui and Hawaii Island—are already extremely small in size or are represented by only a few occasional individuals, probably owing to the loss of disease-free habitat. Iiwi may face extirpation in these places due to the inability to overcome the effects of malaria. The species is expected to first become restricted to Hawaii Island, perhaps by the year 2040. By the end of the century, the existence of iiwi is uncertain due to the ongoing loss of disease-free habitat; the potential impacts to ohia forests from ROD and other stressors could increase the risk to iiwi as well. These threats to iiwi are ongoing, most are rangewide, are expected to increase in the future, and are significant because they will likely result in increased mortality of iiwi and loss of remaining populations, as well as further decreases in the availability and amount of disease-free habitat at high elevation. As discussed above, the existing regulatory mechanisms are not sufficient to address these threats (Factor D).

Some of the other stressors contributed to past declines in iiwi, or negatively affect the species or its habitat today; however, of the additional stressors considered, we found no information to suggest that any is currently a key factor in the ongoing declines in abundance and range of iiwi, although they may be contributing or exacerbating factors. Habitat loss and alteration (Factor A) caused by nonnative plants and ungulates is occurring rangewide, has resulted in degraded ohia forest habitat, and is not likely to be reduced in the future. While ohia forests still comprise the majority of native forest cover on most of the main Hawaiian Islands, climate change and its likely effects, such as increased drought frequency, are expected to further affect ohia forest habitat and compound other impacts, including the spread of invasive plants and perhaps the severity and frequency of ohia diseases. In particular, ROD, the rapidly spreading and highly lethal tree disease, poses an increasing risk to the native forest habitat of iiwi on Hawaii Island, where 90 percent of remaining iiwi occur. This emerging factor has the potential to exacerbate avian disease and other stressors in the future by accelerating the loss and degradation of iiwi's habitat. If this disease becomes widespread, it could further increase the vulnerability of the iiwi by eliminating the native forest it requires for foraging and nesting.

We do not have any information that overutilization for commercial, recreational, scientific, or educational purposes (Factor B) poses a threat to iiwi.

The Act defines an endangered species as any species that is “in danger of extinction throughout all or a significant portion of its range” and a threatened species as any species “which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.” We considered whether the iiwi meets either of these definitions, and find that the iiwi meets the definition of a threatened species for the reasons described below.

We considered whether the iiwi is currently in danger of extinction and determined that endangered status is not appropriate. Although the species has experienced significant reductions in both abundance and range, at the present time the species is still found on multiple islands, and the species as a whole still occurs in relatively high numbers. Additionally, disease-free habitat currently remains available for iiwi in high-elevation ohia forests with temperatures sufficiently cool to prevent the development of the malarial parasite. For these reasons, we do not consider the iiwi to be in imminent danger of extinction, although this formerly common species has experienced threats of such severity and magnitude that it has now become highly vulnerable to continued decline and local extirpation, such that the species is likely to become endangered within the foreseeable future, as explained below.

Based on our review of the best scientific and commercial data available, we expect that additional iiwi population declines will be observed range-wide within the next few decades, and indications are that declines are already taking place on Kauai and in some Maui and Hawaii Island populations as a result of increasing temperatures and consequent exposure to avian malaria at some elevations where the disease is uncommon or absent today. Iiwi has a very high observed mortality rate when exposed to avian malaria, and the warming effects of climate change will result in increased exposure of the remaining iiwi populations to this disease, especially at high elevation. Peer-reviewed results of modeling experiments project that malaria transmission rates and effects on iiwi populations will begin increasing at high elevations by mid-century, and result in population declines of 70 to 90 percent by the year 2100. We thus conclude that the iiwi is likely to become in danger of extinction throughout all of its range within the foreseeable future. Because the iiwi is not in imminent danger of extinction, but is likely to become in danger of extinction within the foreseeable future, it meets the definition of a threatened species. Therefore, on the basis of the best available scientific and commercial information, we are listing the iiwi as a threatened species in accordance with sections 3(20) and 4(a)(1) of the Act.

Under the Act and our implementing regulations, a species may warrant listing if it is endangered or threatened throughout all or a significant portion of its range. Because we have determined that the iiwi is threatened throughout all of its range, under the Final Policy on Interpretation of the Phrase “Significant Portion of Its Range” in the Endangered Species Act's Definitions of “Endangered Species and “Threatened Species” (79 FR 37577 (July 1, 2014)) (SPR Policy), if a species warrants listing throughout all of its range, no portion of the species' range can be a “significant” portion of its range. While it is the Service's position under the SPR Policy that undertaking no further analysis of “significant portion of its range” in this circumstance is consistent with the language of the Act, we recognize that the Policy is currently under judicial review, so we also took the additional step of considering whether there could be any significant portions of the species' range where the species is in danger of extinction. We evaluated whether there is substantial information indicating that there are any portions of the species' range: (1) That may be “significant,” and (2) where the species may be in danger of extinction. In practice, a key part of identifying portions appropriate for further analysis is whether the threats are geographically concentrated. For the iiwi, the primary driver of its status is avian malaria. The prevalence of this disease is moving upslope in Hawaiian forests correlated with temperature increases associated with climate change. These threats are affecting the species throughout its entire range; therefore, there is not a meaningful geographical concentration of threats. As a result, even if we were to undertake a detailed SPR analysis, there would not be any portions of the species' range where the threats are harming the species to a greater degree such that it is in danger of extinction in that portion.

Conservation measures provided to species listed as endangered or threatened species under the Act include recognition, recovery actions, requirements for Federal protection, and prohibitions against certain practices. Recognition from listing will result in public awareness and conservation by Federal, State, Tribal, and local agencies, private organizations, and individuals. The Act encourages cooperation with the States and other countries and calls for recovery actions to be carried out for listed species. The protection required by Federal agencies and the prohibitions against certain activities are discussed, in part, below.

The primary purpose of the Act is the conservation of endangered and threatened species and the ecosystems upon which they depend. The ultimate goal of such conservation efforts is the recovery of these listed species, so that they no longer need the protective measures of the Act. Subsection 4(f) of the Act calls for the Service to develop and implement recovery plans for the conservation of endangered and threatened species. The recovery planning process involves the identification of actions that are necessary to halt or reverse the species' decline by addressing the threats to its survival and recovery. The goal of this process is to restore listed species to a point where they are secure, self-sustaining, and functioning components of their ecosystems.

Recovery planning includes the development of a recovery outline shortly after a species is listed and preparation of a draft and final recovery plan. The recovery outline guides the immediate implementation of urgent recovery actions and describes the process to be used to develop a recovery plan. Revisions of the plan may be done to address continuing or new threats to the species, as new substantive information becomes available. The recovery plan also identifies recovery criteria for review of when a species may be ready for downlisting or delisting, and methods for monitoring recovery progress. Recovery plans also establish a framework for agencies to coordinate their recovery efforts and provide estimates of the cost of implementing recovery tasks. Recovery teams (composed of species experts, Federal and State agencies, nongovernmental organizations, and other qualified persons) are often established to develop recovery plans. When completed, the recovery outline, draft recovery plan, and the final recovery plan for iiwi will be available on our Web site (http://www.fws.gov/endangered), or from our Pacific Islands Fish and Wildlife Office (see FOR FURTHER INFORMATION CONTACT). The public will have an opportunity to comment on the draft recovery plan, and the Service will consider all information presented during the public comment period prior to approval of the plan.

Implementation of recovery actions generally requires the participation of a broad range of partners, including other Federal agencies, States, Tribes, nongovernmental organizations, businesses, and private landowners. Examples of recovery actions include habitat restoration (e.g., restoration of native vegetation), research, captive propagation and reintroduction, and outreach and education. The recovery of many listed species cannot be accomplished solely on Federal lands because their range may occur primarily or solely on non-Federal lands. To achieve recovery of these species requires cooperative conservation efforts on private, State, and Tribal lands. If this species is listed, funding for recovery actions will be available from a variety of sources, including Federal budgets, State programs, and cost-share grants for non-Federal landowners, the academic community, and nongovernmental organizations. In addition, pursuant to section 6 of the Act, the State of Hawaii would be eligible for Federal funds to implement management actions that promote the protection or recovery of the iiwi. Information on our grant programs that are available to aid species recovery can be found at: http://www.fws.gov/grants.

Please let us know if you are interested in participating in recovery efforts for this species. Additionally, we invite you to submit any new information on this species whenever it becomes available and any information you may have for recovery planning purposes (see FOR FURTHER INFORMATION CONTACT).

Section 7(a) of the Act requires Federal agencies to evaluate their actions with respect to any species that is listed as an endangered or threatened species and with respect to its critical habitat, if any is designated. Regulations implementing this interagency cooperation provision of the Act are codified at 50 CFR part 402. Section 7(a)(2) of the Act requires Federal agencies to ensure that activities they authorize, fund, or carry out are not likely to jeopardize the continued existence of the species or destroy or adversely modify its critical habitat. If a Federal action may affect a listed species or its critical habitat, the responsible Federal agency must enter into consultation with the Service.

Federal agency actions within the iiwi's habitat that may require a conference or consultation or both as described in the preceding paragraph, include but are not limited to, management and any other landscape-altering activities on Federal lands administered by the U.S. Fish and Wildlife Service, U.S. Forest Service, and National Park Service; actions within the jurisdiction of the Natural Resources Conservation Service, the U.S. Army Corps of Engineers, the U.S. Fish and Wildlife Service, and branches of the Department of Defense (DOD); and activities funded or authorized under the Federal Highway Administration, Partners for Fish and Wildlife Program, and DOD construction activities related to training or other military missions.

Under section 4(d) of the Act, the Service has discretion to issue regulations that we find necessary and advisable to provide for the conservation of threatened species. We are not proposing to issue a special rule pursuant to section 4(d) for this species. Therefore, the provisions of 50 CFR 17.31(a) and (b) would apply. These regulatory provisions apply the prohibitions of section 9(a)(1) of the Act to threatened wildlife and make it illegal for any person subject to the jurisdiction of the United States to take (which includes harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect; or to attempt any of these) threatened wildlife within the United States or on the high seas. In addition, it is unlawful to import, export, deliver, receive, carry, transport, or ship in interstate or foreign commerce in the course of commercial activity; or sell or offer for sale in interstate or foreign commerce any listed species. It is also illegal to possess, sell, deliver, carry, transport, or ship any such wildlife that has been taken illegally. Certain exceptions apply to employees of the Service, the National Marine Fisheries Service, other Federal land management agencies, and State conservation agencies.

We may issue permits to carry out otherwise prohibited activities involving threatened wildlife under certain circumstances. Regulations governing permits are codified at 50 CFR 17.32. With regard to threatened wildlife, a permit may be issued for the following purposes: For scientific purposes, to enhance the propagation or survival of the species, or for incidental take in connection with otherwise lawful activities. There are also certain statutory exemptions from the prohibitions, which are found in sections 9 and 10 of the Act.

It is our policy, as published in the Federal Register on July 1, 1994 (59 FR 34272), to identify to the maximum extent practicable at the time a species is listed, those activities that would or would not constitute a violation of section 9 of the Act. The intent of this policy is to increase public awareness of the effect of a final listing on proposed and ongoing activities within the range of a listed species. Based on the best available information, actions that may result in a violation of section 9 include but are not limited to:

(1) Development of land or the conversion of native ohia forest, including the construction of any infrastructure (e.g., roads, bridges, railroads, pipelines, utilities) in occupied iiwi habitat;

(2) Unauthorized collecting, handling, possessing, selling, delivering, carrying, or transporting of the species, including import or export across State lines and international boundaries, except for properly documented antique specimens of this species at least 100 years old, as defined by section 10(h)(1) of the Act;

(3) Introduction of nonnative species that compete with or prey upon the iiwi, such as the new introduction of nonnative predators or competing birds to the State of Hawaii; and

(4) Certain research activities: Collection and handling of iiwi for research that may result in displacement or death of individuals.

Questions regarding whether specific activities would constitute a violation of section 9 of the Act should be directed to the Pacific Islands Fish and Wildlife Office, Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).

We have determined that environmental assessments and environmental impact statements, as defined under the authority of the National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), need not be prepared in connection with listing a species as an endangered or threatened species under the Endangered Species Act. We published a notice outlining our reasons for this determination in the Federal Register on October 25, 1983 (48 FR 49244).

A complete list of references cited in this rulemaking is available on the Internet at http://www.regulations.gov at Docket No. FWS-R1-ES-2016-0057 and upon request from the Pacific Islands Fish and Wildlife Office (see FOR FURTHER INFORMATION CONTACT).

The primary authors of this final rule are the staff members of the Pacific Islands Fish and Wildlife Office.

Accordingly, we amend part 17, subchapter B of chapter I, title 50 of the Code of Federal Regulations, as set forth below:

Executive Summary

Why we need to publish a rule. Under the Endangered Species Act of 1973, as amended (Act, 16 U.S.C. 1531 et seq.), if we determine that a species is an endangered or threatened species throughout all or a significant portion of its range, we are required to promptly publish a proposal in the Federal Register and make a determination on our proposal within 1 year. Listing a species as an endangered or threatened species can only be completed by issuing a rule. We published a proposed rule to add the pearl darter (Percina aurora) to the List of Endangered and Threatened Wildlife in title 50 of the Code of Federal Regulations (50 CFR 17.11(h)) as threatened on September 21, 2016 (81 FR 64857).

What this document does. This rule will finalize the listing of the pearl darter as a threatened species.

The basis for our action. Under the Act, we may determine that a species is an endangered or threatened species based on any of five factors: (A) The present or threatened destruction, modification, or curtailment of its habitat or range; (B) overutilization for commercial, recreational, scientific, or educational purposes; (C) disease or predation; (D) the inadequacy of existing regulatory mechanisms; or (E) other natural or manmade factors affecting its continued existence. We have determined that water quality decline from point and nonpoint source pollution continues to impact portions of this species' habitat. In addition, geomorphology changes attributed to historical sand and gravel mining operations within the drainage are considered an ongoing threat. This species has been extirpated from the Pearl River watershed and is confined today to the Pascagoula River basin where the species' small population size, scattered locations, and low genetic (allelic) diversity increase its vulnerability to extirpation from catastrophic events.

Peer review and public comment. We sought comments from independent specialists to ensure that our determination was based on scientifically sound data, assumptions, and analyses. We invited these peer reviewers to comment on our listing proposal. We also considered all comments and information received from the public during the comment period.

Please refer to the September 21, 2016, proposed listing rule (81 FR 64857) for a detailed description of previous Federal actions concerning this species.

For a more detailed discussion of the taxonomy, biology, status, and threats affecting the species, please refer to the proposed listing rule. In the proposed rule, we evaluated the biological status of the species and factors affecting its continued existence. Our assessment was based upon the best available scientific and commercial data on the status of the species, including past, present, and future threats.

In the proposed rule, we requested that all interested parties submit written comments on the proposal by November 21, 2016. We also contacted appropriate Federal and State agencies, scientific experts and organizations, and other interested parties and invited them to comment on the proposal. Newspaper notices inviting general public comment were published in the Hattiesburg American, Mississippi Press, and Clarion-Ledger on October 2, 2016. We did not receive any requests for a public hearing. All substantive information provided during the comment period has either been incorporated directly into this final determination or is addressed in the more specific response to comments below.

In accordance with our peer review policy published on July 1, 1994 (59 FR 34270), we solicited expert opinion from three individuals with scientific expertise that included familiarity with pearl darter and its habitat, biological needs, and threats. We received responses from all three of the peer reviewers.

We reviewed all comments received from the peer reviewers for new substantive information regarding the listing of the pearl darter. The peer reviewers generally concurred with our methods and conclusions and provided additional information, clarifications, and suggestions to improve the final rule. Where appropriate, we incorporated new information into the final rule as a result of the peer reviewer comments, including new survey information. Other substantive peer reviewer comments are below.

(1) Comment: One peer reviewer suggested our statement that the species was extirpated from the Pearl River drainage was premature, since surveys in that system were ongoing, and cautioned that a final listing decision should be withheld until surveys were completed.

Our Response: While upper Pearl River basin surveys for the pearl darter were completed in 2011 (Schaefer and Mickle 2011), surveys for the darter in the lower Pearl River drainage were only completed by the Mississippi Department of Wildlife, Fisheries, and Parks in May of 2017 (Wagner et al. 2017, entire). Those surveys, which included both traditional surveys and eDNA analysis (Wagner et al. 2017, p. 5), were utilized over the last 2 years in an attempt to locate evidence of this species persisting in the Pearl River system. Our determination that the pearl darter has not been collected from the Pearl River drainage in over 40 years, and is considered extirpated from this system, is validated by these recent survey results.

(2) Comment: One peer reviewer stated that pulp mills should be considered a threat to water quality degradation. The reviewer also expressed a suspicion that pulp mill effluent may have had some influence on extirpation of pearl darters in the Pearl River.

Our Response: We agree and have made changes to this final rule to reflect the peer reviewer's input in the Summary of Factors Affecting the Species section, below.

(3) Comment: One peer reviewer stated that increased demand for water withdrawal by industry and municipalities should be considered an additional threat to the species in the Pascagoula drainage. The reviewer stated that this activity will be a continuing threat for all aquatic resources as coastal populations grow and industrial needs expand. The commenter cited the 2006 proposed Richton Salt Dome as an example of water withdrawal posing a threat to the pearl darter.

Our Response: We agree that water withdrawal from the Pascagoula drainages could have an impact on the ecological health of the system and potentially impact the pearl darter. However, at this time, we have no information to indicate that increased demand for water withdrawal by industry and municipalities currently poses a threat to the pearl darter, and we note that the peer reviewer did not identify any specific active projects. The Richton Salt Dome project cited by the peer reviewer, which at one time was a concern, was terminated and removed from the Department of Energy's budget in 2011.

(4) Comment: One peer reviewer stated that there was no information to indicate there has been a decline in pearl darter abundance in the Bouie River and Black Creek and, particularly, no information attributing any declines to sedimentation and unstable banks. These areas have historically had few specimens of darter and have not been thoroughly surveyed.

Our Response: We agree that there are inadequate data and a lack of thorough surveying of the Bouie River and Black Creek to definitively note a decline of the species in those systems, and we have clarified the rule accordingly. Until recently, there had been no collection efforts in the Bouie River and Black Creek since 2000. However, in 2016-2017, survey efforts in these systems found pearl darters to be sparsely present in a few sites (Schaefer in litt. 2017). Evidence of substantial sedimentation and unstable banks in the Bouie River and Black Creek has been documented in the past (Mossa and Coley 2004, p. 7; Mississippi Department of Environmental Quality 2005c, p. 16) and observed currently (Schaefer in litt. 2017). The negative impact of excessive sedimentation on darter distribution is well known and addressed under Factor A in the Summary of Factors Affecting the Species section of the preamble to this rule. Furthermore, there are also likely other factors contributing to water quality degradation in these systems, such as point and nonpoint source pollution related to stormwater runoff and effluent discharge from industry, agriculture, and urbanization; therefore, we have revised our statement regarding sedimentation.

(5) Comment: One peer reviewer commented that our statement in the proposed rule on low genetic diversity and restricted gene flow as reported by Kreiser et al. (2012) ran counter to the hypothesized long-distance spawning migrations noted elsewhere in the rule. The commenter stated that the genetic data support a series of potentially disjunct populations rather than one contiguous population.

Our Response: We appreciate the comment and have clarified in this final listing rule the statement that pearl darters may have long-distance spawning migrations (Bart et al. 2001, p. 14). Kreiser's (et al. 2012, pp. 14-17) recent genetic studies, indicating a series of potentially disjunct populations, are likely a more accurate representation of the population structure of the pearl darter (see Summary of Factors Affecting the Species, Factor E).

The proposed rule was reviewed by the Mississippi Department of Wildlife, Fisheries and Parks; the Mississippi Forestry Commission; and the Louisiana Department of Wildlife and Fisheries. The individual associated with the Mississippi Department of Wildlife, Fisheries and Parks also served as a peer reviewer, and his comment is addressed in Comment 1 above. The State agencies generally concurred with our methods and commented that the literature and data were thorough and properly documented. They stated that we should withhold our final listing decision until their surveys in the Pearl River drainage had been completed. Mississippi Department of Wildlife, Fisheries and Parks recently provided additional information from their recent site surveys. The Louisiana Department of Wildlife and Fisheries agreed that there were no recent records from the Pearl River system despite recent sampling efforts. An issue raised by the Mississippi Forestry Commission is addressed below.

(6) Comment: The Mississippi Forestry Commission and two commenters from the timber industry stated that we mischaracterized the use of best management practices (BMPs) in Mississippi by stating that: (1) Their use was confined to lands managed by The Nature Conservancy and the State of Mississippi, and (2) the lack of a mandatory requirement makes forestry BMPs less effective. The commenters pointed out that the forest industry has a number of forest certification programs, such as the Sustainable Forestry Initiative, which require participating landowners to meet or exceed State forestry BMPs. The commenters also stated that silviculture practices implemented with BMPs have minimal impacts on aquatic species, and that a recent statewide monitoring survey by Mississippi Forestry Commission indicated that BMPs are being implemented across all silviculture landscapes in Mississippi regardless of ownership.

Our Response: We appreciate the additional information provided by the commenters and commend the timber industry and landowners on their implementation of BMPs in their timber operations and also the success of forestry certification programs, such as Sustainable Forestry Initiative. We have updated information in this rule to acknowledge the contribution of these forest landowners implementing BMPs in the Summary of Factors Affecting the Species section, below.

We received five comments from the public, two of which are addressed in Comment 6, above; the three other commenters simply expressed their support for the proposed listing.

This final rule incorporates minor changes to our proposed rule based on the comments we received, as discussed above in Summary of Comments and Recommendations, and newly available survey information. The survey data allowed us to refine distribution information; thus, the final total current range of the species is different from that in the proposed rule. Many small, nonsubstantive changes and corrections were made throughout the document in response to comments (e.g., updating the Background section, threats, minor clarifications). However, the information we received in response to the proposed rule did not change our determination that the pearl darter is a threatened species, nor was it significant enough to warrant reopening the public comment period. Below is a summary of substantive changes made to the final rule.

• We now estimate the total current range of the pearl darter in the Pascagoula watershed to be 668 kilometers (km) (415 miles (mi)) based on a reanalysis of collection records and recent survey results. Detailed information about the species' range within each of the seven river/creek systems is presented in the preamble of this rule, under Current Distribution.

• Additional information on habitat and population structure from peer reviewers and recent studies (Wagner et al. 2017) has been added to the preamble.

• Additional information and suggestions from peer reviewers was added to clarify and improve the accuracy of the information in the Distribution, Habitat, Biology, and Threats sections of the preamble to the proposed rule.

• Additional information on the species' abundance and probable cause of decline in the Pearl River, as related to the potential threat to existing populations in the Pascagoula system, from two peer reviewers was added into the Summary of Factors Affecting the Species section of this rule, below.

• Additional narrative on historical threats within the Pearl River basin, as well as additional historical and current threats affecting water quality within the Pascagoula River basin, including increased brine concentration from oil and gas production and pulp mill effluent related to pulp, paper, and lumber mills, was added to the preamble.

Below we present a summary of the biological and distributional information discussed in the proposed listing rule (81 FR 64857; September 21, 2016). We also present new information published or obtained since the proposed rule was published (see Summary of Changes from the Proposed Rule, above).

The pearl darter (Percina aurora) is a small fish and is one of three members of the subgenus Cottogaster (Ross 2001, p. 500). The species is allied to the channel darter (P. copelandi) (Ross et al. 1989, p. 25) but is distinguished from it by its larger size, lack of tubercules (small, raised, skin structures), heavy pigmentation, number of marginal spines on belly scales of breeding males, and fully scaled cheeks (Suttkus et al. 1994, pp. 13-14). Generally, pearl darters range in size from 22 to 59 millimeters (mm) (0.87 to 2.3 inches (in)) in length with the majority of adults being from 30 to 41 mm (1.2 to 1.6 in) long (Clark and Schaefer 2015, p. 10).

The pearl darter is historically known from localized sites within the Pearl and Pascagoula River drainages in Mississippi and Louisiana, based on collection records from 16 counties and parishes of Mississippi and Louisiana. Examination of site records of museum fish collections from the Pearl River drainage (compiled from Suttkus et al. 1994, pp. 15-18) suggests that the pearl darter once inhabited the large tributaries and main channel habitats within these drainages from St. Tammany Parish, Louisiana, to Simpson County, Mississippi. This area totaled approximately 708 km (440 mi) within the Pearl River basin and included the lower Pearl River, the Strong River, and the Bogue Chitto River (compiled from MMNS 2016, unpublished data; Slack et al. 2005, pp. 5-10; Ross 2001, p. 499; Ross et al. 2000, pp. 2-5; Bart and Piller 1997, pp. 3-10; Bart and Suttkus 1996, pp. 3-4; Suttkus et al. 1994, pp. 15-18). However, there have been no records of this species from the Pearl River drainage in over 40 years, despite repeated collecting efforts through the years (Wagner et al. 2017, pp. 3-10, 12; Geheber and Piller 2012, pp. 633-636; Schaefer and Mickel 2011, p. 10; Slack et al. 2005, pp. 5-10; Tipton et al. 2004, pp. 56-57; Ross 2001, p. 499; Bart and Piller 1997, p. 1; Bart and Suttkus 1996, pp. 3-4; Bart and Suttkus 1995, pp. 13-14; Suttkus et al. 1994, pp. 15-18). Survey efforts over the last few years at all historical sites, including north of and just below the Ross Barnett Reservoir (Schaefer and Mickle 2011, pp. 8-10), have confirmed its absence from the Pearl River system (Wagner et al. 2017, pp. 3-4; Roberts in litt. 2015; Geheber and Piller 2012, p. 633), including the recent analysis of water samples for eDNA from the Pearl River proper, Strong River, and Bogue Chitto River (Piller in litt. 2017). Thus, the pearl darter is considered extirpated from the Pearl River system today.

Today, the pearl darter occurs in scattered sites within an approximately 668-km (415-mi) area of the Pascagoula drainage, including the Pascagoula (101 km, 63 mi), Chickasawhay (257 km, 160 mi), Leaf (186 km, 115 mi), Chunky (31 km, 19 mi), and Bouie (24 km, 15 mi) Rivers and Okatoma (37 km, 23 mi) and Black Creeks (32 km, 20 mi) (Wagner et al. 2017, pp. 3-10, 12; Wagner in litt. 2017; Clark and Schaefer 2015, pp. 10, 19, 23; Schaefer and Mickle 2011, pp. 1-3; Slack et al. 2002, p. 9).

The average catch at known occupied sites, using standard sampling (30 minutes with heavy leaded seine) is 2.1 individuals (Wagner et al. 2017. pp. 3-4; Clark and Schaefer 2015, pp. 9-14, 18-22), indicating a species that is rare. Surveys by Kreiser et al. (2012, pp. 29-32) found sporadic occurrences of the species within the Pascagoula River from its headwaters at the confluence of the Leaf and Chickasawhay Rivers downstream to where the river bifurcates (splits). Recent survey efforts indicate reproducing populations in the Chickasawhay and Leaf Rivers, based on the presence of different size classes (Clark in litt. 2017; Wagner in litt. 2017; Wagner et al. 2017, p. 3; Schaefer in litt. 2017; Clark and Schaefer 2015, pp. 9-14, 18-22). Though there is a clear pattern of higher abundance and greater rate of occurrence at sites in the Chickasawhay River (5.03 ± 0.62 pearl darters per hour) compared to the Leaf River (2.18 ± 0.56 pearl darters per hour); a pattern that has remained constant over time (Clark and Schaefer 2015, pp. 9-14). Surveys in 2016 of historical locations (Clark in litt. 2017; Schaefer in litt. 2017) in the Bouie River, Okatoma Creek, and Black Creek yielded seven fish in the Okatoma Creek and one specimen each in the Bouie River and Black Creek. In 2017, one pearl darter was collected in the Chunky River, confirming its presence in that system for the first time since its last collection there over 15 years ago.

The pearl darter occurs in low-gradient, coastal plain rivers and creeks (Suttkus et al. 1994, p. 13), predominately classified as 4th to 2nd order streams (Strahler stream order hierarchy). There have been no comprehensive microhabitat studies on the pearl darter; however, based on observations of occupancy in the field, microhabitat features consist of a bottom substrate mixture of sand, silt, loose clay, gravel, organic material, and snags (Slack et al. 2005, pp. 9-11). The species has been collected at the steep ends of sandbars, and inside river bends where material is deposited. The water where the species is typically captured has a slow to medium current velocity (0.003 to 0.635 centimeters/second (cm/s) (0.53 to 0.25 in/s) (tabulated from Clark in litt. 2017, Slack in litt. 2017, Schaefer in litt. 2017, unpublished data; Slack et al. 2005, p. 10). In fact, based on cluster analysis and ordination of habitat data of the Leaf and Chickasawhay Rivers, higher densities of pearl darters were found in slower moving, deeper waters with finer substrate (Clark and Schaefer 2015, p. 11). There is very little aquatic vegetation in these drainages (Slack et al. 2005, p. 9), and vegetation that may be present is usually river weed (Podostemum ceratophyllum) attached to rocks (Drennen and Wagner 2017, pers. observ.). Banksides where the pearl darter was collected are vegetative and not vertical or severely eroded (Schaefer in litt. 2017, unpublished data).

There is no specific information available on the diet of the pearl darter. However, the channel darter (P. copelendi), a closely allied species in similar habitat, has been reported to feed on chironomid flies, small crustaceans, mayflies, and caddisflies (Kuehne and Barbour 1983, p. 49).

Below we present a summary of the threats information from the proposed listing rule. We also present new information published or obtained since the proposed rule was published, including information received during the public comment period.

Members of the Cottogaster subgenus have undergone range contractions that are of potential conservation concern throughout their respective distributions (Dugo et al. 2008, p. 3; Warren et al. 2000, pp. 7-8; Goodchild 1994, pp. 433-435). The pearl darter was extirpated from the Pearl River drainage, perhaps as early as the 1970s, and many of the stressors thought to have played a role in its loss in that system are present in the Pascagoula River drainages where the species occurs today, including impoundments (sills and dams); instability in the channel; increased sedimentation from the removal of riparian vegetation and poor agriculture and silviculture practices; and general chronic water degradation from point and non-point source pollution (Piller et al. 2004, pp. 1004-1011; TNC 2004, p. 5; Ross 2001, pp. 499-500).

Water quality degradation, particularly non-point source pollution from incompatible commercial and industrial development and land use practices, has been a major concern within the Pearl River basin (TNC 2004, p. 18). Similarly, the Pascagoula River system suffers from acute and localized water quality degradation by nonpoint source pollution in association with surface, stormwater, and effluent runoffs from urbanization and municipal areas (MDEQ 2005c, p. 23; 2005d, p. 16). “Total Maximum Daily Loads” (TMDLs), a term in the U.S. Clean Water Act describing a benchmark set for a certain pollutant to bring water quality up to the applicable standard, have been established for 89 segments of the Pascagoula River basin, many of which include portions of the pearl darter's range (MDEQ 2014a, pp. 18-21). For sediment, one of the most pervasive pollutants, the State of Mississippi has TMDLs for various tributaries and main stems of the Leaf and Chickasawhay Rivers. To date, efforts by the State of Mississippi to improve water quality in the Pascagoula River basin to meet these TMDL benchmarks have been inadequate (MDEQ 2014a, pp. 18-21). Thirty-nine percent of the Pascagoula River basin tributaries are rated fair or poor due to pollution impacts (MDEQ 2014a, pp. 18-21; MDEQ 2008, p. 17).

Most water quality threats are due to increased sediment loads and variations in pH (MDEQ 2014a, pp. 1-51; 2008a, pp. 13-15). Sediment in stormwater runoff increases water turbidity and temperature and originates locally from poorly maintained construction sites, timber harvest tracts, agricultural fields, clearing of riparian vegetation, and gravel extraction in the river floodplain. Suttkus et al. (1994, p. 19) attributed the loss of the pearl darter in the Pearl River to increasing sedimentation from habitat modification caused by the removal of riparian vegetation and extensive cultivation near the river's edge. Excessive sediments disrupt feeding and spawning of fish and aquatic insects, abrade and suffocate periphyton (mixture of algae, bacteria, microbes, and detritus that is attached to submerged surfaces), and impact fish growth, survival, and reproduction (Waters 1995, pp. 55-62). A localized portion of the Chickasawhay River is on the State Section 303(d) List of Water Bodies as impaired due to sediment (MDEQ 2005b, p. 17).

Nonpoint source pollution is a localized threat to the pearl darter within the drainage, and is more prevalent in areas where certified best management practices (BMPs) are not utilized. The use of certified BMPs during land-altering activities can greatly reduce impacts to water quality. Certified BMPs, currently implemented by the forestry industry (e.g., Sustainable Forestry Initiative, Forest Stewardship Council, and American Tree Farm System), are helping to minimize or eliminate non-point source pollution during the course of forestry activities. The Mississippi Forestry Commission (2016, entire) reports certified BMP implementation rates to be high in Mississippi for forestry activities, primarily due to the efforts of State forestry agencies and forest certification programs (Schilling and Wigley 2015, pp. 3-7).

Historically, timber harvesting and processing was extensive in the Pearl River basin, and at one time, the basin was home to one of the most important lumber centers in the United States (Thigpen 1965, pp. 66-69). Pulp and paper manufacturing began in the Pascagoula watershed in Mississippi with three major mills (Monthly Review 1958, p. 83). Today, there are six major pulp mills in the Pascagoula River basin whose effluent may be a threat to the pearl darter. Paper mill effluent is a contributor to water quality degradation and is suspected to have had some influence on the extirpation of the pearl darter in the Pearl River system (Slack in litt. 2016). Fish and mussel kills were reportedly not uncommon within reaches downstream from pulp mills in Lawrence County near historical locations for the pearl darter (Slack in litt. 2016). As recently as 2011, a “black liquor” (wastewater) spill from a paper manufacturing process resulted in a massive fish kill in the Pearl River (Kizha et al. 2016, pp. 926-929; Piller and Geheber 2015, pp. 2433-2434).

Numerous studies have documented the effects of pulp and paper mill effluents on fish populations (Beyer et al. 1996, pp. 212-224). Depending on the bleaching process, pulp- and paper mill effluents may contain various kinds and concentrations of chlorinated organic compounds such as polychlorinated dibenzodioxins (dioxins) and polychlorinated dibenzofurans (furans), which elicit several lethal and sublethal effects in fish, such as alterations in steroid biosynthesis (manufacturing of hormones and other organic compounds), gonadal (sex gland) development, sexual maturation, and expression of secondary sex characteristics (features that appear at maturity such as coloration). These types of compounds are known to bioaccumulate and have reproductive and antiestrogen (opposite effects of hormones) impacts on fish (Hoffman et al. 2003, pp. 1063-1065).

Additionally, some contaminants may bind with one another (i.e., heavy metals bind with sediments or other contaminants in the water column) within the Pascagoula River drainage. These bound chemical contaminants have not been addressed in TMDLs. Only seven TMDLs for metals have been completed (MDEQ 2008, pp. 1-55). The Davis Dead River, a tributary at the most downstream site of the pearl darter's range, is considered critically impaired by mercury (MDEQ 2011, pp. 1-29), and fish consumption advisories continue for mercury in certain gamefish species in the Pascagoula River main stem (MDEQ 2008, p. 43).

There are 15 permitted point source discharge sites within the Bouie River system (MDEQ 2005a, p. 6) and an unknown amount of nonpoint runoff sites. Municipal and industrial discharges during periods of low flow (i.e., no or few rain events) intensify water quality degradation by increasing water temperatures, lowering dissolved oxygen, and changing pH. Within the Pascagoula River basin, pollutants causing specific channel or river reach impairment (i.e., those pollutants preventing the water body from reaching its applicable water quality standard (Environmental Protection Agency 2012, pp. 1-9)), include sedimentation; chemicals and nutrients in the water column; and various toxins, such as heavy metals like lead or cadmium for a total of 304 km (189 mi) impaired riverine segments. TMDLs were completed for pesticides such as dichlorodiphenyltrichloroethane (DDT), toxaphene, dioxin, and pentachlorophenol, although much of the data and results are not finalized and remain unavailable for the designated reaches (Environmental Protection Agency 2012, pp. 1-7; MDEQ 2003, pp. 5-10; Justus et al. 1999, p. 1).

Localized wastewater effluent into the Leaf River from the City of Hattiesburg is negatively impacting water quality (Hattiesburg American 2015, pp. 1-2; Mississippi River Collaboration 2014, p. 1). Existing housing, recreational cabins, and trailers along the banks of the Leaf River between I-59 and the town of Estabutchie cause nutrient loading through treated sewage and septic water effluent (Mississippi River Collaboration 2014, p. 1). In 1997, Bart and Piller (p. 12) noted extensive algal growth during warmer months in the Leaf and Bouie Rivers, indicating nutrient and organic enrichment and decreases in dissolved oxygen and pH changes. Today, at specific locations, the water quality of the Bouie and Leaf Rivers and their tributaries continues to be negatively impacted by sediment, organic enrichment, low dissolved oxygen, fecal coliform, and elevated nutrients (MDEQ 2016, p. 86, 91; 2014a, p. 18, 21, 32; 2005a, pp. 1-26; 2004, pp. 1-29).

Nonpoint and point source pollution from oil and gas exploration, including drill field construction, active drilling, and pipeline easements, may add localized pollutants into the Pascagoula River basin during stormwater runoff events if BMPs are not used. There is one major oil refinery within the basin along with 6 oil pumping stations, 10 major crude pipelines, 4 major product oil pipelines, and 5 major gas and more than 25 lesser gas lines stretching hundreds of miles and crisscrossing the main stem Pascagoula, Bouie, Leaf, Chickasawhay, and Chunky Rivers and their tributaries; in addition, there are more than 100 active oil producing wells within the pearl darters' watersheds (compiled from Oil and Gas Map of Mississippi in Phillips 2013, pp. 10, 23). All have the potential to rupture or leak and cause environmental and organismal damage as evidenced by the Genesis Oil Company and Leaf River oil spill of 2000 (Environmental Science Services, Inc. 2000, pp. 1-50; Kemp Associates, PA, 2000, pp. 4-5; The Clarion-Ledger, December 23, 1999, p. 1B) and Genesis Oil Company spill in Okatoma Creek in February 2016 (Drennen 2016, pers. observ.). In addition to gas pipelines, there are numerous railways that cross pearl darter habitat that are subject to accidental and catastrophic spilling of toxins such as fuel oil, methanol, resin, and fertilizer (MDEQ 2014b, pp. 1-23).

Alternative oil and gas collection methods (i.e., hydraulic fracturing (“fracking”) and horizontal drilling and injection) have allowed the expansion of oil and gas drilling into deposits that were previously inaccessible (Phillips 2013, p. 21), which has led to increased activity within southern Mississippi, including portions of the Pascagoula River basin. There are more than 100 water injection disposal wells and enhanced oil recovery wells within the basin (compiled from Active Injection Well Map of Mississippi in Phillips 2013, p. 49). A variety of chemicals (e.g., 15% diluted hydrochloric acid, surfactants, potassium chloride) are used during the drilling and fracking process (Colborn et al. 2011, pp. 1040-1042), and their wastes are stored in open pits (retention basins) or storage facilities. Spills during transport or releases due to retention basin failure or overflow pose a risk for surface and groundwater contamination, which can cause significant adverse effects to water quality and aquatic organisms that inhabit these watersheds (Osborn et al. 2011, pp. 8172-8176; Kargbo et al. 2010, pp. 5680-5681; Wiseman 2009, pp. 127-142). In addition, contamination of streams with brine (chloride), a byproduct of oil and gas development, poses a significant risk to aquatic habitats and species. High chloride concentrations interfere with osmoregulation (maintenance of proper levels of salts and other solutes in bodily fluids) and hinder the organism's survival, growth, and reproduction (Hunt et al. 2012, p. 1). Brine contamination has been documented within the pearl darter's historical range in the Pearl River system (Kalhoff 1993, pp. 12-15, 19-20, 25; Kalhoff 1986, p. 49) and within the Pascagoula River basin where it currently occurs, including several Leaf and Chickasawhay River drainage basin tributaries (Kalhoff 1986, pp. 52-63). There is currently no routine water quality monitoring in areas where the pearl darter currently occurs, so it is unlikely that the effects of a leak or spill would be detected quickly enough to allow for a timely response.

Piller et al. (2004, pp. 1004-1011) cited numerous human-caused disturbances within the Pearl River since the 1950s, including channelization, reservoir construction, and channel modification from bank collapse downstream of dams. Specifically, the Pearl River Navigation Canal in 1956, the Ross Barnett Reservoir in 1964, and channel changes of the lower Pearl River (increased width and decreased depth) were implicated in the decline of abundance for several fish species in that system (Piller et al. 2004, pp. 1004-1011). These habitat modifications and channel changes resulted in the loss of gravel substrates in places, completely replacing gravel bars with sand or sediment, which are not appropriate substrate for the pearl darter and other species (Tipton et al. 2004, pp. 58-60; TNC 2004, p. 5). Tipton et al. (2004, pp. 58-60) documented a decrease in fish diversity and abundance within the disturbed reaches as compared with relatively undisturbed reaches. These changes most likely contributed to the decline of the pearl darter in the Pearl River system and potentially threaten the species in the Pascagoula system.

Pearl darters are not found in impounded waters and are intolerant of lentic (standing water) habitats that may be formed by gravel mining or other landscape-altering practices. Incompatible sand and gravel mining and its disruption of topography, vegetation, and flow pattern of streams is considered a major stressor to the Pearl River system where the pearl darter once occurred (TNC 2004, p. 16). In the species' current range in the Pascagoula system, the results of historical sand and gravel dredging impacts have been a concern for the Bouie and Leaf Rivers (MDEQ 2000, pp. 1-98). Historically, the American Sand and Gravel Company (1995, p. B4) has mined sand and gravel using a hydraulic suction dredge, operating within the banks or adjacent to the Bouie and Leaf Rivers. Large gravel bars of the river and its floodplain have been removed over the past 50 years, creating open-water areas that function as deep lake systems (American Sand and Gravel Company 1995, pp. B4-B8). The creation of these large, open-water areas has accelerated geomorphic processes, specifically headcutting (erosional feature causing an abrupt drop in the streambed) that has adversely affected the flora and fauna of many coastal plain streams (Patrick et al. 1993, p. 90). Mining in active river channels typically results in incision upstream of the mine by knickpoints (breaks in the slope of a river or stream profile caused by renewed erosion attributed to a bottom disturbance that may retreat upstream), sediment deposition downstream, and an alteration in channel morphology that can have impacts for years (Mossa and Coley 2004, pp. 1-20). The upstream migration of knickpoints, or headcutting, may cause undermining of structures, lowering of alluvial water tables (aquifer comprising unconsolidated materials deposited by water and typically adjacent to rivers), channel destabilization and widening, and loss of aquatic and riparian habitat. This geomorphic change may cause the extirpation of riparian and lotic (flowing water) species (Patrick et al. 1993, p. 96).

Sedimentation from unstable banks and loose, unconsolidated streambeds (Bart and Piller 1997, p. 12) is likely impacting the pearl darters in the Bouie River and Black Creek. Mossa and Coley (2004, p. 17) determined that, of the major tributaries in the Pascagoula basin, the Bouie River was the least stable. Channel enlargement of the Bouie River showed higher than background values associated with avulsions (the rapid abandonment of a river channel and the formation of a new river channel) into floodplain pits and increased sedimentation. In addition, channel enlargement of 400 to 500 percent in the Bouie River has occurred at specific sites due to instream gravel mining (Mossa et al. 2006, entire; Mossa and Coley 2004, p. 17). Ayers (2014, pp. 43-45) also found significant and lengthy instream channel form changes in the Chickasawhay River floodplain. Clark and Schaefer (2015, pp. 13-14) noted a slight decrease in fish species richness in the upper Pascagoula River basin from their 2004 sampling, which they attributed to past anthropogenic influences such as gravel mining, bankside practices, and construction.

In the Bogue Chitto River of the Pearl River basin, Stewart et al. (2005, pp. 268-270) found that the assemblages of fishes had shifted over 27 years. In this time period, the sedimentation rates within the system had increased dramatically and caused the decrease in the relative abundance of all fish in the family Percidae (Stewart et al. 2005, pp. 268-270) from 35 percent to 9 percent, including the extirpation of pearl darters. Ross et al. (1992, pp. 8-9) studied threats to the Okatoma Creek (Pascagoula basin) fish diversity and predicted that geomorphic changes to the stream would reduce the fish habitat diversity resulting in a decline of the fish assemblages, including the pearl darter.

Dams and other flow control structures within a river can block fish passage, disrupt the natural flow patterns, and cause channel degradation and erosion (see “Geomorphology Changes” section above) that directly impact aquatic life habitat, as well as reduce the capacity of the stream to carry water (TNC 2004, p. 17). Streams with highly altered flow regimes often become wide, shallow, and homogeneous, resulting in poor habitat for many fish species (Bunn and Arthington 2002, pp. 493-498). The decline of the pearl darter in the Pearl River was noted after the construction of low sill dams. Bart (in TNC 2004, p. 5) speculated that, after spawning, young darters in the Pearl River were swept downriver and unable to migrate back upriver due to the low water sills and varied water flow; their limited success year after year likely caused the population to crash. These low sill dams are also thought to have led to the extirpation of the Alabama shad (Alosa alabamae) from that system (Mickel et al. 2010, p. 158).

The proposed damming of Little and Big Cedar Creeks, tributaries to the Pascagoula River, for establishment of two recreational lakes (George County Lakes) (U.S. Army Corps of Engineers 2015, pp. 1-13) has prompted the American Rivers organization to recently list the Pascagoula River as the 10th most endangered river in the country (American Rivers 2016, pp. 20-21). Though the proposed project is not directly within known pearl darter habitat, the lakes may decrease water quantity entering the lower Pascagoula basin and will likely concentrate pollutants, reduce water flow, and alter downstream food webs and aquatic productivity (Poff and Hart 2002, p. 660).

Habitat modification and resultant water quality degradation are occurring within the pearl darter's current range and likely led to the loss of the species from the Pearl River drainage. Water quality degradation occurs locally from point and nonpoint source pollution in association with land surface, stormwater, and effluent runoff from urbanization, industry, and municipal areas. Of particular concern is the threat of overflooding of storage ponds for industrial effluent, such as that from pulp and paper manufacturing. Increased sediment from a variety of sources, including geomorphological changes and bank instability from past habitat modification, appears to be the major contributor to water quality declines in this species' habitat. Localized sewage and waste water effluent also pose a threat to this species and its habitat. The pearl darter's vulnerability to catastrophic events, particularly the release of pollutants in its habitat from oil spills, train derailments, and hydraulic fracturing, is also a concern due to the abundance of oil wells, pumping stations, gas lines, and railways throughout its habitat, and the increased interest in alternative oil and gas collection methods in the area. The proposed damming of Big and Little Cypress Creeks may decrease water flow and increase nutrient concentration into the Pascagoula River. These threats continue to impact water quality and habitat conditions through much of this species' current range. Therefore, we conclude that habitat degradation is presently a moderate threat to the pearl darter that is expected to continue and possibly increase into the future.

The pearl darter is not a commercially valuable species, and collecting is not considered a factor in its decline. Therefore, we do not consider overutilization for commercial, recreational, scientific, or educational purposes to be a threat to the pearl darter at this time.

We have no specific information indicating that disease or predation is negatively impacting pearl darter populations. Therefore, we do not consider these factors to be threats to the pearl darter at this time.

The State of Mississippi classifies the pearl darter as endangered (Mississippi Natural Heritage Program 2015, p. 2), and prohibits the collection of the pearl darter for scientific purposes without a State-issued collecting permit. However, as discussed under Factor B, we have no evidence to suggest that scientific collection poses a threat to this species. This State classification conveys no legal protection for the pearl darter's habitat nor does it prohibit habitat degradation, which is the primary threat to the species. The pearl darter receives no protection in Louisiana, where it is considered to have historically occurred (Louisiana Department of Wildlife and Fisheries 2005, p. 39).

The pearl darter and its habitats are afforded some protection from water quality and habitat degradation under the Clean Water Act of 1972 (33 U.S.C. 1251 et seq.) and the Mississippi Water Pollution Control Law, as amended, 1993 (Code of Mississippi, section 49-17-1, et seq.) and regulations promulgated thereunder by the Mississippi Commission on Environmental Quality. Although these laws have resulted in some enhancement in water quality and habitat for aquatic life, particularly in reducing point-source pollutants, they have been inadequate in fully protecting the pearl darter from sedimentation and other nonpoint source pollutants.

The State of Mississippi maintains water-use classifications through issuance of National Pollutant Discharge Elimination System permits to industries, municipalities, and others that set maximum limits on certain pollutants or pollutant parameters. For water bodies on the Clean Water Act section 303(d) list of impaired streams, the State is required to establish a TMDL for the pollutants of concern that will improve water quality to the applicable standard. The establishment of TMDLs for 89 river or stream segments and ratings of fair to poor for 39 percent of the tributaries within the Pascagoula basin are indicative of water pollution impacts within the pearl darter's habitat (MDEQ 2008a, p. 17). TMDLs are not an enforced regulation, and only reflect benchmarks for improving water quality; they have not been successful in reducing water quality degradation within this species' habitat, as these streams continue to remain on the 303(d) list of impaired streams.

Mississippi Surface Mining and Reclamation Law, Miss. Code Ann. section 53-7-1 et seq., and Federal laws regarding oil and gas drilling (42 U.S.C. 6921) are generally designed to protect freshwater resources like the pearl darter, but these regulatory mechanisms do not contain specific provisions requiring an analysis of project impacts to fish and wildlife resources. They also do not contain or provide for any formal mechanism requiring coordination with, or input from, the Service or the Mississippi Department of Wildlife, Fisheries and Parks regarding the presence of federally endangered, threatened, or candidate species, or other rare and sensitive species. In the case of surface mining, penalties may be assessed if damage is serious, but there is no immediate response for remediation of habitats or species. As demonstrated under Factor A, periodic declines in water quality and degradation of habitat for this species are ongoing despite these protective regulations. These mechanisms have been inadequate to protect the species from sediment runoff and turbidity within its habitat associated with land surface runoff and municipal and industrial discharges, as described under Factor A. There are currently no requirements within the scope of other statewide environmental laws to specifically consider the pearl darter or ensure that a project will not significantly impact the species.

The pearl darter likely receives ancillary protection (i.e., water quality improvements, protection from geomorphological changes) where it co-occurs with two other federally listed species, the Gulf sturgeon (Acipenser oxyrhynchus desotoi) and yellow-blotched map turtle (Graptemys flavimaculata), during the course of consultation on these species under section 7 of the Act. However, protective measures through section 7 of the Act would be triggered only for those projects having a Federal nexus, which would not include many of the water quality disturbances caused by industry, municipalities, agriculture, or private landowners.

Additional protection of 53,520 hectares (ha) (132,128 acres (ac)) within the Pascagoula basin watershed occurs due to the Mississippi Wildlife, Fisheries and Parks' management of six Wildlife Management Areas (WMAs) within the upper drainage basin for recreational hunting and fishing. Four of the six WMAs (Chickasawhay and Leaf Rivers, Mason and Red Creeks) do not directly border the river system, but they do contain and protect parcels of upland buffer, wetland, and tributaries to the basin. The Pascagoula River and Ward Bayou WMAs (20,329 ha; 50,234 ac) consist of wetland buffer and river/stream reach protecting approximately 106 km (66 mi) of the Pascagoula River main stem (Stowe in litt. 2015). The Nature Conservancy (TNC) protects 14,164 ha (35,000 ac) within the Pascagoula River watershed and approximately 10 km (6 mi) of the Pascagoula River shoreline in Jackson County, Mississippi. Of that amount, the Charles M. Deaton Nature Preserve (1,336 ha, 3,300 ac) protects the upper reaches of the Pascagoula River, where the Leaf and Chickasawhay Rivers converge, and is part of a 19,020-ha (47,000-ac) swath of public lands surrounding the Pascagoula River, which includes approximately 8 km (5 mi) of the Chickasawhay River and approximately 7 km (4 mi) of the Leaf River shorelines (Stowe in litt. 2015).

These State-managed WMAs and TNC preserves provide a measure of protection for approximately 134 km (84 mi) or 30 percent of the river reaches within this species' current range. Point and nonpoint sediment sources are decreased or reduced by using and monitoring certified BMPs during silviculture, road maintenance, and other landscape-altering activities. However, only short segments of shoreline in the Chickasawhay and Leaf Rivers are within these WMAs. Remaining lands within these segments can be vulnerable to farming and timbering to the bankside edge, and construction of structures such as houses, septic facilities, dams, and ponds. Each land management action can increase stormwater runoff laden with sediment and agricultural and wastewater chemicals. The impact of silvicultural activities on water quality degradation are likely lower than other land-altering activities according to information in the Mississippi Forestry Commission's report (2016, entire) that found certified BMP implementation rates to be high across all silvicultural landscapes in Mississippi.

Despite existing authorities such as the Clean Water Act, pollutants continue to impair the water quality throughout much of the current range of the pearl darter. State and Federal regulatory mechanisms have helped reduce the negative effects of point source and nonpoint source discharges, yet these regulations are difficult to implement, and may not provide adequate protection for sensitive species like the pearl darter. Thus, we conclude that existing regulatory mechanisms do not adequately protect the pearl darter from the impact of other threats.

The pearl darter has always been considered rare (Deacon et al. 1979, p. 42) and is currently restricted to localized sites within the Pascagoula River drainage. Genetic diversity has likely declined due to fragmentation and separation of reproducing pearl darter populations. Kreiser et al. (2012, pp. 12-17) found that disjunct populations of pearl darters within the Leaf and Chickasawhay Rivers showed some distinct alleles suggesting that gene flow between the two rivers was restricted and perhaps that the total gene pool diversity was declining. Collecting data (Ross 2001, p. 500; Bart and Piller 1997, p. 4; Bart and Suttkus 1996, p. 4; Suttkus et al. 1994, p. 19) indicate that the pearl darter is rare in the Pascagoula River system, as when this species is collected it is typically in low numbers and a disproportionately low percentage of the total fish collected (catch per unit effort of 2.1 individuals per site, Clark and Shaefer 2015, p. 4).

Species that are restricted in range and population size are more likely to suffer loss of genetic diversity due to genetic drift, potentially increasing their susceptibility to inbreeding depression, decreasing their ability to adapt to environmental changes, and reducing the fitness of individuals (Allendorf and Luikart 2007, pp. 117-146; Soulé 1980, pp. 157-158). It is likely that some of the pearl darter populations are below the effective population size required to maintain long-term genetic and population viability (Soulé 1980, pp. 162-164).

The long-term viability of a species is founded on the conservation of numerous local populations throughout its geographic range (Harris 1984, pp. 93-104). The presence of viable, separate populations is essential for a species to recover and adapt to environmental change (Noss and Cooperrider 1994, pp. 264-297; Harris 1984, pp. 93-104). Inbreeding and loss of neutral genetic variation associated with small population size reduces the fitness of the population (Reed and Frankham 2003, pp. 230-237) and accelerates population decline (Fagan and Holmes 2006, pp. 51-60). The species' small numbers within scattered locations, coupled with its lack of genetic variability, may decrease the species' ability to adapt or recover from major hydrological events that impact potential spawning habitat (Clark and Schaefer 2015, pp. 18-22).

Fish and aquatic communities and habitat, including that of the pearl darter, may be changed by hurricanes (Schaefer et al. 2006, pp. 62-68). In 2005, Hurricane Katrina destroyed much of the urban and industrial areas along the lower Pascagoula River basin and also impacted the ecology upriver to the confluence with the Leaf and Chickasawhay Rivers. Many toxic chemicals that leaked from grounded and displaced boats and ships, storage facilities, vehicles, septic systems, business sites, and other sources due to the hurricane were reported in the rivers, along with saltwater intrusion from the Gulf of Mexico. Initial assessment identified several fish kills and increased surge of organic material into the waters, which lowered dissolved oxygen levels (Schaefer et al. 2006, pp. 62-68). As discussed below, the deleterious impacts of climate change will likely lead to an increase in the strength and frequency of hurricanes.

Numerous long-term climate changes have been observed including widespread changes in precipitation amounts, ocean salinity, wind patterns, and aspects of extreme weather including droughts, heavy precipitation, heat waves, and the intensity of tropical cyclones (Intergovernmental Panel on Climate Change 2014, p. 4). Climate change, and the resultant shifts in spatial distribution, may result in increased fragmentation which would increase the vulnerability of any isolated populations to future extinction (Comet et al. 2013, p. 635). However, while continued change is certain, the magnitude and rate of change is unknown in many cases.

Climate change has the potential to increase the vulnerability of the pearl darter to random catastrophic events (Thomas et al. 2004, pp. 145-148; McLaughlin et al. 2002, pp. 6060-6074). An increase in both severity and variation in climate patterns is expected, with extreme floods, strong storms, and droughts becoming more common (Intergovernmental Panel on Climate Change 2014, pp. 58-83). Thomas et al. (2004, pp. 145-148) report that frequency, duration, and intensity of droughts are likely to increase in the Southeast as a result of global climate change. Kaushal et al. (2010, p. 465) reported that stream temperatures in the Southeast have increased roughly 0.2-0.4 °C (0.3-0.7 °F) per decade over the past 30 years, and as air temperature is a strong predictor of water temperature, stream temperatures are expected to continue to rise. Predicted impacts of climate change on fishes, related to drought, include disruption to their physiology (e.g., temperature tolerance, dissolved oxygen needs, and metabolic rates), life history (e.g., timing of reproduction, growth rate), and distribution (e.g., range shifts, migration of new predators) (Comte et al. 2013, pp. 627-636; Strayer and Dudgeon 2010, pp. 350-351; Heino et al. 2009, pp. 41-51; Jackson and Mandrak 2002, pp. 89-98). However, estimates of the effects of climate change using available climate models typically lack the geographic precision needed to predict the magnitude of effects at a scale small enough to discretely apply to the range of a given species. Therefore, there is uncertainty about the specific effects of climate change (and their magnitude) on the pearl darter. However, climate change is almost certain to affect aquatic habitats in the Pascagoula River basin through increased water temperatures resulting in stronger storm surges and more frequent droughts (Alder and Hostetler 2013, pp. 1-12), and species with limited ranges, fragmented distributions, and small population sizes are thought to be especially vulnerable to the effects of climate change (Byers and Norris 2011, p. 18).

The pearl darter's limited geographic range, fragmented distribution within the Pascagoula River system, small population numbers, and low genetic diversity threaten this species' long-term viability. These threats are current and are likely to continue or increase in the future, and would be exacerbated by climate change.

The threats that affect the pearl darter are important on a threat-by-threat basis but are even more significant in combination. Due to the loss of the species from the Pearl River system, the pearl darter is now confined to a single drainage system. The species continues to be subjected to water quality degradation from point and nonpoint source pollution in association with land-altering activities, discharges from municipalities, and geomorphological changes from past gravel mining. The laws and regulations directed at preventing water quality degradation have been ineffective at providing for the conservation of the pearl darter. Furthermore, these threats and their effect on this species are exacerbated due to the pearl darter's small population numbers, localized distribution, and low genetic diversity, which reduce its genetic fitness and resilience to possible catastrophic events. Though projecting possible synergistic effects of climate change on the pearl darter is somewhat speculative, climate change, and its effects of increased water temperatures leading to stronger storms and more frequent droughts, will have a greater negative impact on species with limited ranges and small population sizes, such as the pearl darter. While these threats or stressors may act in isolation, it is more probable that many stressors are acting simultaneously (or in combination) on the pearl darter, having a greater cumulative negative effect than any individual stressor or threat.

We have carefully assessed the best scientific and commercial information available regarding the past, present, and future threats to the pearl darter. The pearl darter has been extirpated from the Pearl River system, and it is now confined to the Pascagoula River watershed. The species occurs in low numbers within its current range, and continues to be at risk throughout all of its range due to the immediacy, severity, and scope of threats from habitat degradation and range curtailment (Factor A) and other natural or manmade factors affecting its continued existence (Factor E). Existing regulatory mechanisms have been inadequate in ameliorating these threats (Factor D).

Anthropogenic activities, such as general land development, agriculture and silviculture, oil and gas development (especially when BMPs were not implemented during these activities), along with inadequate sewage treatment, uncontrolled stormwater runoff, pulp mill effluent, past gravel mining and resultant geomorphological changes, and construction of dams or sills, have all contributed to the degradation of stream habitats and water quality within this species' range (Factor A). These land use activities have led to chemical and physical changes in the main stem rivers and tributaries that continue to affect the species through negative impacts to its habitat. Specific water quality threats include inputs of sediments covering bottom stream substrates, increased turbidity, and inputs of dissolved solids. These threats, especially the inputs of dissolved solids, chemical-laden effluent, sedimentation, and geomorphic changes, have had profound negative effects on pearl darter populations, as demonstrated in the Pearl River basin, and have been the primary factor in the species' decline. Existing regulatory mechanisms (e.g., the Clean Water Act) have provided for some improvements in water quality and habitat conditions across the species' range, but these laws and regulations have been inadequate in protecting the species' habitat (Factor D), as evidenced by the extirpation of the species within the Pearl River basin and by the number of section 303(d) listed streams within the species' historical and current range. The pearl darter's vulnerability to these threats is even greater due to its reduced range, scattered locations of small populations, and low genetic diversity (Factor E).

The Act defines an endangered species as any species that is “in danger of extinction throughout all or a significant portion of its range” and a threatened species as any species “that is likely to become endangered throughout all or a significant portion of its range within the foreseeable future.” We find that the pearl darter is likely to become endangered throughout all or a significant portion of its range within the foreseeable future, based on the immediacy, severity, and scope of the threats currently impacting the species. Foreseeable future for this species was determined to be approximately 20 years, which is based on our best professional judgement of the projected future conditions related to threats identified impacting this species. The overall range has been reduced substantially, and the remaining habitat and populations are threatened by a variety of factors acting in combination to reduce the overall viability of the species over time. The threats are not expected to change substantially within this 20-year timeframe, as water quality degradation continues to pose a risk locally despite existing regulations, and land development and land-altering activities are expected to increase. The risk of becoming endangered during this time is high because populations confined to this single watershed are fragmented and genetic diversity within the species is low. Many of the populations are small and likely below the effective population size needed to maintain long-term population viability which makes this species particularly vulnerable to catastrophic events. Though there is uncertainty about the magnitude of effects of climate change on the pearl darter, the frequency and intensity of storms affecting the Pascagoula River watershed are evident today and predicted to increase during this timeframe.

We find that endangered species status is not appropriate for this species. Despite low population numbers and numerous threats, the Chickasawhay and Leaf Rivers, within the upper Pascagoula River drainage, appear to support reproducing populations. In addition, the magnitude of threats is considered to be moderate overall, since the threats are having a localized impact on the species and its habitat. For example, water quality degradation, the most prevalent threat, is not as pervasive within areas where BMPs are utilized, and geomorphic changes caused by historic sand and gravel mining are also sporadic within its habitat. Therefore, on the basis of the best available scientific and commercial information, we are listing the pearl darter as threatened in accordance with sections 3(6) and 4(a)(1) of the Act.

Under the Act and our implementing regulations, a species may warrant listing if it is endangered or threatened throughout all or a significant portion of its range. Because we have determined that the pearl darter is threatened throughout all of its range, no portion of its range can be “significant” for purposes of the definitions of “endangered species” and “threatened species.” See the Final Policy on Interpretation of the Phrase “Significant Portion of Its Range” in the Endangered Species Act's Definitions of “Endangered Species” and “Threatened Species” (79 FR 37577, July 1, 2014). While it is the Service's position under the Policy that undertaking no further analysis of “significant portion of its range” in this circumstance is consistent with the language of the Act, we recognize that the Policy is currently under judicial review, so we also took the additional step of considering whether there could be any significant portions of the species' range where the species is in danger of extinction. We evaluated whether there is substantial information indicating that there are any portions of the species' range: (1) That may be “significant,” and (2) where the species may be in danger of extinction. In practice, a key part of identifying portions appropriate for further analysis is whether the threats are geographically concentrated. The threats affecting the species are throughout its entire range; therefore, there is not a meaningful geographical concentration of threats. As a result, even if we were to undertake a detailed “significant portion of its range” analysis, there would not be any portions of the species' range where the threats are harming the species to a greater degree such that it is in danger of extinction in that portion.

Section 3(5)(A) of the Act defines critical habitat as “(i) the specific areas within the geographical area occupied by the species, at the time it is listed...on which are found those physical or biological features (I) essential to the conservation of the species and (II) which may require special management considerations or protection; and (ii) specific areas outside the geographical area occupied by the species at the time it is listed...upon a determination by the Secretary that such areas are essential for the conservation of the species.”

Section 4(a)(3) of the Act and implementing regulations (50 CFR 424.12) require that we designate critical habitat at the time a species is determined to be an endangered or threatened species, to the maximum extent prudent and determinable. In our September 21, 2016, proposed rule to list the darter (81 FR 64857), we determined that designation of critical habitat was prudent. We also found that critical habitat for the pearl darter was not determinable because the specific information sufficient to perform the required analysis of the impacts of the designation is currently lacking, such as information on areas to be proposed for designation and the potential economic impacts associated with designation of these areas. We are continuing the process of obtaining information on the economic impacts of our critical habitat designation, and, once this process is completed, we intend to publish our proposed critical habitat designation for the pearl darter in the Federal Register and request public input.

Conservation measures provided to species listed as endangered or threatened species under the Act include recognition, recovery actions, requirements for Federal protection, and prohibitions against certain practices. Recognition through listing results in public awareness, and conservation by Federal, State, Tribal, and local agencies, private organizations, and individuals. The Act encourages cooperation with the States and requires that recovery actions be carried out for all listed species. The protection required by Federal agencies and the prohibitions against certain activities are discussed, in part, below.

The primary purpose of the Act is the conservation of endangered and threatened species and the ecosystems upon which they depend. The ultimate goal of such conservation efforts is the recovery of these listed species, so that they no longer need the protective measures of the Act. Subsection 4(f) of the Act requires the Service to develop and implement recovery plans for the conservation of endangered and threatened species. The recovery planning process involves the identification of actions that are necessary to halt or reverse the species' decline by addressing the threats to its survival and recovery. The goal of this process is to restore listed species to a point where they are secure, self-sustaining, and functioning components of their ecosystems.

Recovery planning includes the development of a recovery outline shortly after a species is listed and preparation of a draft and final recovery plan. The recovery outline guides the immediate implementation of urgent recovery actions and describes the process to be used to develop a recovery plan. Revisions of the plan may be done to address continuing or new threats to the species, as new substantive information becomes available. The recovery plan identifies site-specific management actions that set a trigger for review of the five factors that control whether a species remains endangered or may be downlisted or delisted, and methods for monitoring recovery progress. Recovery plans also establish a framework for agencies to coordinate their recovery efforts and provide estimates of the cost of implementing recovery tasks. Recovery teams (composed of species experts, Federal and State agencies, nongovernmental organizations, and stakeholders) are often established to develop recovery plans. When completed, the recovery outline, draft recovery plan, and the final recovery plan will be available on our Web site (http://www.fws.gov/endangered) or from our Mississippi Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).

Implementation of recovery actions generally requires the participation of a broad range of partners, including other Federal agencies, States, Tribal, nongovernmental organizations, businesses, and private landowners. Examples of recovery actions include habitat restoration (e.g., restoration of native vegetation), research, captive propagation and reintroduction, and outreach and education. The recovery of many listed species cannot be accomplished solely on Federal lands because their range may occur primarily or solely on non-Federal lands. To achieve recovery of these species requires additional cooperative conservation efforts on private, State, and Tribal lands.

Following publication of this final listing rule, funding for recovery actions will be available from a variety of sources, including Federal budgets, State programs, and cost share grants for non-Federal landowners, the academic community, and nongovernmental organizations. In addition, pursuant to section 6 of the Act, the State of Mississippi will be eligible for Federal funds to implement management actions that promote the protection or recovery of the pearl darter. Information on our grant programs that are available to aid species recovery can be found at: http://www.fws.gov/grants.

Please let us know if you are interested in participating in recovery efforts for the pearl darter. Additionally, we invite you to submit any new information on this species whenever it becomes available and any information you may have for recovery planning purposes (see FOR FURTHER INFORMATION CONTACT).

Section 7(a) of the Act requires Federal agencies to evaluate their actions with respect to any species that is listed as an endangered or threatened species and with respect to its critical habitat, if any is designated. Regulations implementing this interagency cooperation provision of the Act are codified at 50 CFR part 402. Section 7(a)(1) requires Federal agencies to utilize their authorities in furtherance of the purposes of the Act by carrying out programs for the conservation of endangered and threatened species listed pursuant to section 4 of the Act. Section 7(a)(2) of the Act requires Federal agencies to ensure that activities they authorize, fund, or carry out are not likely to jeopardize the continued existence of any endangered or threatened species or destroy or adversely modify its critical habitat. If a Federal action may affect a listed species or its critical habitat, the responsible Federal agency must enter into consultation with the Service.

Federal agency actions within the species' habitat that may require consultation as described in the preceding paragraph include actions on lands under ownership by the U.S. Army Corps of Engineers, the issuance of section 404 Clean Water Act permits by the U.S. Army Corps of Engineers, construction and maintenance of gas and oil pipelines and power line rights-of-way by the Federal Energy Regulatory Commission, Environmental Protection Agency pesticide registration, construction and maintenance of roads or highways by the Federal Highway Administration, and funding of various projects administered by the U.S. Department of Agriculture's Natural Resources Conservation Service and the Federal Emergency Management Agency.

Under section 4(d) of the Act, the Service has discretion to issue regulations that we find necessary and advisable to provide for the conservation of threatened species. The Act and its implementing regulations set forth a series of general prohibitions and exceptions that apply to threatened wildlife. The prohibitions of section 9(a)(1) of the Act, as applied to threatened wildlife and codified at 50 CFR 17.31, make it illegal for any person subject to the jurisdiction of the United States to take (which includes harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect; or to attempt any of these) threatened wildlife within the United States or on the high seas. In addition, it is unlawful to import; export; deliver, receive, carry, transport, or ship in interstate or foreign commerce in the course of commercial activity; or sell or offer for sale in interstate or foreign commerce any listed species. It is also illegal to possess, sell, deliver, carry, transport, or ship any such wildlife that has been taken illegally. Certain exceptions apply to employees of the Service, the National Marine Fisheries Service, other Federal land management agencies, and State conservation agencies.

We may issue permits to carry out otherwise prohibited activities involving threatened wildlife under certain circumstances. Regulations governing permits are codified at 50 CFR 17.32. With regard to threatened wildlife, a permit may be issued for the following purposes: For scientific purposes, to enhance the propagation or survival of the species, and for incidental take in connection with otherwise lawful activities. There are also certain statutory exemptions from the prohibitions, which are found in sections 9 and 10 of the Act.

It is our policy, as published in the Federal Register on July 1, 1994 (59 FR 34272), to identify to the maximum extent practicable at the time a species is listed, those activities that would or would not constitute a violation of section 9 of the Act. The intent of this policy is to increase public awareness of the effect of a final listing on proposed and ongoing activities within the range of a listed species. Based on the best available information, the following actions are unlikely to result in a violation of section 9, if these activities are carried out in accordance with existing regulations, permit requirements, or certification programs; this list is not comprehensive:

(1) Normal agricultural and silvicultural practices, including herbicide and pesticide use, which are carried out in accordance with existing regulations, permit and label requirements, and certified best management practices (i.e., Sustainable Forestry Initiative, Forest Stewardship Council, and American Tree Farm System).

(2) Normal residential and urban landscape activities, such as mowing, edging, fertilizing, etc.

(3) Normal pipeline/transmission line easement maintenance.

(4) Normal bridge, culvert, and roadside maintenance consistent with appropriate best management practices for these activities.

Based on the best available information, the following activities may potentially result in a violation of section 9 of the Act; this list is not comprehensive:

(1) Unauthorized handling or collecting of the species.

(2) Introduction of nonnative fish that compete with or prey upon the pearl darter.

(3) Unlawful discharge or dumping of toxic chemicals, contaminants, sediments, fracking and oil waste water, waste water effluent, or other pollutants into waters supporting the pearl darter that kills or injures individuals, or otherwise impairs essential life-sustaining behaviors such as spawning, feeding, or sheltering.

(4) Destruction or alteration of the species' habitat (e.g., unpermitted instream dredging, impoundment, water diversion or withdrawal, channelization, discharge of fill material, modification of tributaries, channels, or banks) that impairs essential behaviors such as spawning, feeding, or sheltering, or results in killing or injuring a pearl darter.

(5) Unpermitted gravel mining, oil and gas processes, silviculture, and agricultural processes that result in direct or indirect destruction of riparian bankside habitat or in channel habitat in waters supporting the pearl darter that kills or injures individuals, or otherwise impairs essential life-sustaining behaviors such as spawning, feeding, or sheltering.

Questions regarding whether specific activities would constitute a violation of section 9 of the Act should be directed to the Mississippi Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).

We have determined that environmental assessments and environmental impact statements, as defined under the authority of the National Environmental Policy Act, need not be prepared in connection with listing a species as an endangered or threatened species under the Endangered Species Act. We published a notice outlining our reasons for this determination in the Federal Register on October 25, 1983 (48 FR 49244).

In accordance with the President's memorandum of April 29, 1994 (Government-to-Government Relations with Native American Tribal Governments; 59 FR 22951), Executive Order 13175 (Consultation and Coordination With Indian Tribal Governments), and the Department of the Interior's manual at 512 DM 2, we readily acknowledge our responsibility to communicate meaningfully with recognized Federal Tribes on a government-to-government basis. In accordance with Secretarial Order 3206 of June 5, 1997 (American Indian Tribal Rights, Federal-Tribal Trust Responsibilities, and the Endangered Species Act), we readily acknowledge our responsibilities to work directly with tribes in developing programs for healthy ecosystems, to acknowledge that tribal lands are not subject to the same controls as Federal public lands, to remain sensitive to Indian culture, and to make information available to tribes. The pearl darter is not known to occur within any tribal lands or waters.

A complete list of references cited in this rulemaking is available on the Internet at http://www.regulations.gov and upon request from the Mississippi Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).

The primary authors of this final rule are the staff members of the Mississippi Ecological Services Field Office.

Accordingly, we amend part 17, subchapter B of chapter I, title 50 of the Code of Federal Regulations, as follows:

Previous Federal Action

Please refer to the proposed listing rule for the Sonoyta mud turtle (81 FR 64829; September 21, 2016) for a detailed description of previous Federal actions concerning this subspecies.

We completed a comprehensive assessment of the biological status of the Sonoyta mud turtle, and prepared a report of the assessment, which provides a thorough account of the subspecies' overall viability. We define viability as the ability of the subspecies to persist over the long term and avoid extinction. In this section, we summarize the conclusions of that assessment, which can be accessed at Docket No. FWS-R2-ES-2016-0103 on http://www.regulations.gov and at http://www.fws.gov/southwest/es/arizona/. The Sonoyta mud turtle's Species Status Assessment (SSA Report; Service 2017, chapter 4) contains a detailed discussion of our evaluation of the biological status of the Sonoyta mud turtle and the influences that may affect its continued existence.

To assess Sonoyta mud turtle viability, we used the three conservation biology principles of resiliency, representation, and redundancy (Shaffer and Stein 2000, pp. 306-310). Briefly, resiliency supports the ability of the species to withstand environmental and demographic stochasticity (for example, wet or dry, warm or cold years); representation supports the ability of the species to adapt over time to long-term changes in the environment (for example, climate changes); and redundancy supports the ability of the species to withstand catastrophic events (for example, droughts). In general, the more redundant, representative, and resilient a species is, the more likely it is to sustain populations over time, even under changing environmental conditions. Using these principles, we identified the Sonoyta mud turtle's ecological requirements for survival and reproduction at the individual, population, and subspecies levels, and described the beneficial and risk factors influencing the subspecies' viability.

We evaluated the change in resiliency, representation, and redundancy from the past until the present, and projected the anticipated future states of these conditions. To forecast the biological condition into the future, we devised plausible future scenarios by using expert information on the primary stressors anticipated in the future to the Sonoyta mud turtle: habitat loss and degradation (i.e., surface water loss and riparian vegetation loss), effects of climate change, and small population dynamics. To assess population resiliency of the Sonoyta mud turtle, we evaluated habitat conditions and recruitment over time. To assess representation (as an indicator of adaptive capacity) of the Sonoyta mud turtle, we evaluated the ecological and genetic diversity and connectivity over time. To assess redundancy, we calculated the risk of population extirpations given the catastrophic events. That is, we tallied the number of populations historically, currently, and projected into the future to assess the viability of the subspecies.

The Sonoyta mud turtle is a freshwater turtle encountered in or near water in an otherwise arid environment that commonly experiences drought and extreme heat (ambient temperatures can exceed 45 degrees Celsius (°C) (113 degrees Fahrenheit (°F)). The Sonoyta mud turtle is one of two recognized subspecies of Sonora mud turtle (Kinosternon sonoriense) and has been differentiated from the other subspecies based on shell measurements and DNA analysis (Iverson 1981, p. 62; Rosen 2003, entire; Rosen et al. 2006, entire). The other subspecies, K. s. sonoriense, is commonly referred to as Sonora mud turtle. The Sonoyta mud turtle is an isolated, native endemic found in southern Arizona and northern Sonora, Mexico. The Sonoyta mud turtle is a dark, medium-sized freshwater turtle with a mottled pattern on the head, neck, and limbs. Average lifespan is from 10 to 12 years; however, one has been reported to be 39 years old.

Minimum age of sexual maturity of female Sonoyta mud turtles is just under 6 years, and males around 4 years (Rosen and Lowe 1996, pp. 14-16). Mating occurs in water from April to late June. Ovulation and shelling of eggs begins in June, and eggs remain in the oviducts until the monsoon rains occur from mid to late July through September (van Loben Sels et al. 1997, p. 343). In mid to late July through September, females leave the water briefly to lay eggs in terrestrial nests. Eggs may undergo embryonic diapause (delayed embryo development) in the nest for up to 11 months after being laid. Development begins as eggs warm during the following spring and takes about 80 days, and hatchlings emerge and disperse from the nest the following year to coincide with the onset of summer rains (van Lobel Sels et al. 1997, p. 343; Ernst and Lovich 2009, p. 497; Stone et al. 2015, p. 735).

The Sonoyta mud turtle is found in southern Arizona and northwestern Mexico and depends on aquatic habitat with adjacent terrestrial habitat. Its habitats commonly experience drought and extreme heat. Historically, the Sonoyta mud turtle was limited in its distribution to the Rio Sonoyta basin in Arizona and Sonora, Mexico. There are five historical records of the subspecies being found within three historical perennial sections of the Rio Sonoyta, including the Sonoyta, Santo Domingo, and Papalote (also referred to as Agua Dulce) reaches (Rosen et al. 2010, p. 152), which we assume supported three populations. Perennial waters likely flowed through these three sections of the Rio Sonoyta separated by seasonally ephemeral sections (figure 3.1.1.b of the SSA Report), and groundwater also supported springs and cienegas (wet, marshy areas) in the area (Miller and Fuiman 1987, p. 602; Schoenherr 1988, p. 110; Hendrickson and Varela-Romero 1989, p. 481). These three distinct perennial reaches of the Rio Sonoyta together likely provided 19 to 27 kilometers (km) (12 to 17 miles (mi)) of stream habitat for the Sonoyta mud turtle. The Rio Sonoyta probably flowed for short periods during wet seasons, providing connectivity for mud turtles, with the stream rapidly retracting during the dry season, as it still does today. During periods of above-average precipitation, the river may have been continuous for longer periods, making turtle population connectivity more likely along Rio Sonoyta. We assume that the historical locations of the Sonoyta mud turtles were in areas of the Rio Sonoyta basin that maintained perennial surface water at all times except, possibly, during rare, protracted drought periods. These locations may no longer have reliable surface water to support mud turtles or sufficient surface water to support as large a population as they used to (Paredes-Aguilar and Rosen 2003, p. 2; Rosen et al. 2010, p. 155). Perennial water also existed outside of the Rio Sonoyta in cienegas such as one fed by Quitobaquito Springs on Organ Pipe Cactus National Monument. Quitobaquito Springs is predominately supplied by groundwater (Carruth 1996, pp. 14, 18).

In the SSA Report, we define a population of Sonoyta mud turtles as a group of interbreeding individuals living in an ecological community and separated from other populations by barriers including desert upland (overland, not connected by riparian or xeroriparian habitat) or in-channel distances that lack water most of the time. Currently, five populations of Sonoyta mud turtles occur. Three of these populations are historical populations—Quitobaquito Springs, and the Sonoyta and Papalote reaches of the Rio Sonoyta. However, the Sonoyta reach has now been reduced to a much smaller reach referred to as Xochimilco. There are two new populations—the Sonoyta sewage lagoon and Quitovac in Mexico, which were historically unknown and only discovered in 2002 but likely were present since the 1990s (Knowles et al. 2002, p. 74). These two new populations are not connected hydrologically to each other or to the Rio Sonoyta populations and it is likely that humans transplanted turtles from the Rio Sonoyta to these sites. One other historical population is considered extirpated—Santo Domingo. Of the five extant populations, one is in the United States in the pond and channel associated with Quitobaquito Springs in Organ Pipe Cactus National Monument, Arizona. The other four populations are in Sonora, Mexico (Rosen et al. 2010, p. 152). Two populations in the Rio Sonoyta in the Papalote reach and Xochimilco reach are extant, but perennial water flow in these reaches is reduced from historical levels. Since these perennial reaches in the Rio Sonoyta are greatly reduced or gone, the connectivity among these remaining populations is highly unlikely. The other two extant populations are the Sonoyta sewage lagoon and Quitovac in Mexico. Quitovac consists of multiple springs impounded to form a pond. The Sonoyta sewage lagoon site consists of two lagoons of raw sewage. A new wastewater treatment plant has been constructed to replace the Sonoyta sewage lagoons. However, this new plant has yet to begin operating and it is unclear when it will open. The amount of water and riparian vegetation provided at the new plant is less than that provided at the sewage lagoons and only a portion of the Sonoyta mud turtles are likely to be transplanted.

The population at Quitobaquito Springs has been extensively monitored since the early 1980s. Surveys in the Rio Sonoyta basin in Sonora, Mexico, from 2001 through 2006 provide most of our knowledge of the current populations in Mexico (table 3.2.2 of the SSA Report; Paredes-Aguilar and Rosen 2003, entire; Knowles et al. 2002, entire; Rosen et al. 2010, pp. 152-153). However, we have low confidence that the population sizes for the Sonora populations remain at 2006 levels today, as many changes since the early 2000s have reduced or degraded habitat at most of the sites that still support Sonoyta mud turtles. In October 2001, a single turtle was found in a soup-bowl-sized remnant of water at the semi-perennial spring in the Santo Domingo reach (Santo Domingo is in the Rio Sonoyta and is the location of one of the five historical records of Sonoyta mud turtle listed above; Rosen et al. 2010, pp. 152-153), and we now think this historical population is likely extirpated due to loss of perennial surface water in this reach (Rosen 2016, pers. comm.).

Sonoyta mud turtles depend on aquatic habitat for foraging, shelter, and mating and terrestrial habitat for nesting and estivating. The Sonoyta mud turtle historically occupied habitat in cienegas and streams supported by groundwater-fed springs. Natural aquatic habitats of Sonoyta mud turtles are sustained by groundwater discharged from springs and augmented by seasonal rainfall. Terrestrial habitat that maintains soil moisture needed for Sonoyta mud turtles occurs in riparian areas along the banks of ponds and streams, including intermittently dry sections of a stream channel. However, natural aquatic habitats are highly limited. Sonoyta mud turtles can also be sustained by modified natural habitats or completely human-created habitats that provide similar permanent or almost permanent surface water. Currently, populations still occur within stream habitat, but all the cienegas have been modified from their natural state.

For the Sonoyta mud turtle to maintain viability, its populations, or some portion of its populations, must be resilient enough to withstand stochastic events such as fluctuations in water levels, habitat modification, and introduction of nonnative predators. In the SSA Report, we categorized the potential resiliency of populations of the subspecies. We developed four different resiliency levels: High, medium, low, and none. In a highly resilient Sonoyta mud turtle population, all or the majority of turtles are able to complete their life functions, breeding maintains a stable or increasing population, and the population is able to withstand stochastic events or recover from stochastic events from connected populations. Influencing those factors are elements of Sonoyta mud turtle habitat that determine whether survivorship among age classes is achieved, thereby increasing the resiliency of populations. These factors include perennial or near perennial water (i.e., 10 to 11 months annually for consecutive years) of sufficient volume and extent with connectivity to other populations, terrestrial riparian habitat with soil moisture, high invertebrate prey abundance, and lack of problem nonnative species. The factors used to develop these resiliency levels are discussed below.

Sonoyta mud turtles require perennial or mostly perennial water to complete their life-history functions and avoid desiccation. We define near-perennial as water present more than 10 to 11 months of the year for multiple years. Aquatic habitat in ponds and streams with water 2 meters (m) (6.5 feet (ft)) deep, with a rocky, muddy, or sandy substrate, and emergent or submergent vegetation, or both is needed (NPS 2015, p. 2; Paredes-Aguilar and Rosen 2003, p. 5-7; Rosen 2003, p. 5; Rosen et al. 2010, p. 14). Hatchling, juvenile, and sub-adult turtles prefer aquatic habitat with shallow water and dense emergent vegetation and overhanging vegetation along the stream channel or pond margin that provides foraging opportunities as well as protection from predators (Rosen 1986, pp. 14 and 36; Rosen and Lowe 1996, p. 11). Adults will also use shallow water habitat, but prefer aquatic habitat with accessible, deeper, open water (up to 2 m (6.5 ft)) when available, and submerged vegetation for feeding on benthic and plant-crawling invertebrates along the substrate (Rosen 1986, pp. 14, 16; Rosen and Lowe 1996, p. 11). Adults, juveniles, and subadults also use aquatic habitat with structure that provides protection from predators such as root masses, complex rock features, and undercut banks. Turtle recruitment can be affected by the amount of surface water available, how long it is available, as well as its fluctuation. In addition, hydrologic connectivity is needed for a population to recover from a stochastic event.

Sonoyta mud turtles need terrestrial habitat that maintains soil moisture for Sonoyta mud turtles in riparian areas along the banks of ponds and streams, including intermittently dry sections of stream channels. Riparian habitat provides shadier, cooler, and moister conditions than the adjacent upland areas. Sonoyta mud turtles likely need moist soil for nesting to prevent desiccation of eggs and estivation sites to prevent desiccation of juveniles and adults. Riparian vegetation may also provide some level of protection from terrestrial predators while turtles are out of the water. Sonoyta mud turtles further need accessible shoreline without insurmountable rock or artificial vertical barriers to allow for movement between wetted sites, between aquatic habitat and terrestrial nest sites, and between water and estivation sites.

Sonoyta mud turtle hatchlings and juveniles need shoreline invertebrate fauna, while subadults and adults need bottom dwelling (i.e. on or in the sediment) and plant-crawling invertebrates. Aquatic habitat with emergent and submerged vegetation or the substrate of ponds and streams is needed to support prey for Sonoyta mud turtles (Rosen 1986, pp. 14, 31; Rosen and Lowe 1996, pp. 32-35). Aquatic invertebrates primarily live on and require a variety of prey such as algae, diatoms, and other microorganisms. In habitats with poor aquatic invertebrate faunas, Sonoyta mud turtles will shift to omnivorous feeding, including plants and vertebrates. When invertebrates are abundant, and competition is low, turtles grow rapidly and have sufficient fat content to support reproduction.

Sonoyta mud turtles need aquatic habitat free of problematic nonnative predators and competitors such as crayfish, American bullfrogs, sunfish, black bullheads, African cichlid fishes (tilapia), western mosquitofish, and exotic turtles. Competition between nonnative species and mud turtles for food likely results in disruption of the food chain and alteration of the invertebrate community (Taylor et al. 1984, pp. 330-331; Fernandez and Rosen 1996, pp. 39-40; Duncan 2013, p. 1). Such competition, in turn, likely decreases the type and amount of aquatic invertebrate prey available to Sonoyta mud turtles (Fernandez and Rosen 1996, pp. 39-40) and leads to lower fitness of turtles.

Sonoyta mud turtles need genetic or ecological diversity to adapt to changing environmental conditions. The more representation, or diversity, a species has, the more it is capable of adapting to changes (natural or human-caused) in its environment. Representation can be measured by the breadth of genetic or environmental diversity within and among populations and gauges the probability that a species is capable of adapting to environmental changes. Currently, the Sonoyta mud turtle exhibits genetic and ecological diversity. Maintaining gene flow among populations and counteracting genetic drift and deleterious effects of inbreeding connectivity among populations are needed. A minimum of 1 and maximum of 10 migrants per generation is needed to successfully breed in populations of a species (Mills and Allendorf 1996, p. 1517; Nathan et al. 2017, p. 270; Wang 2004, p. 341). This is a large range of migrants per generation, and we do not know where within this range the Sonoyta mud turtle falls to maintain genetic diversity among the fragmented populations of the subspecies. Genetic analysis conducted in the mid-2000s reveals that successful migration has likely occurred in the past (Rosen 2006, p. 10). Maintaining representation in the form of genetic or ecological diversity is important to maintain the Sonoyta mud turtle's capacity to adapt to future environmental changes.

The Sonoyta mud turtle needs multiple resilient populations spread over its historical range distributed in such a way that a catastrophic event will not result in the loss of all populations. In addition, hydrologic connectivity is needed for a population to recover from a catastrophic event. We do not have an estimate of how many populations are needed to withstand localized loss of habitat and maintain redundancy. However, the loss of Quitobaquito Springs, Quitovac, and either Rio Sonoyta Papalote or Rio Sonoyta Xochimilco would reduce the representation for the subspecies.

The primary negative factor affecting the future viability of the Sonoyta mud turtle is continued loss of water that supports aquatic and riparian habitat. The sources of water loss affecting Sonoyta mud turtles include groundwater pumping, drought, changes to wastewater infrastructure, consumption by livestock, surface water diversion, and habitat manipulation. Of these sources, water loss caused by drought and groundwater pumping, both of which are exacerbated by climate change and changes to wastewater infrastructure, are the primary causes of population-level impacts to the Sonoyta mud turtle. The other sources of water loss are not likely to have population-level impacts unless mining near Quitovac is intensified and unregulated. However, the Quitovac site is routinely dredged, resulting in direct impacts to Sonoyta mud turtles and prey. All of these factors are additive in terms of impacts to populations that are already stressed by the primary activities causing population-level impacts. In addition, impacts from climate change (discussed below) are expected to exacerbate water loss.

Ground water pumping impacts the amount of surface water in areas used by Sonoyta mud turtles because the perennial sections of the Rio Sonoyta as well as the pond at Quitobaquito Springs and Quitovac are supplied by ground water. Diminished water reduces the amount of space, prey, and cover (from predators and for estivation) available to mud turtles. Reduction in aquatic habitat (i.e., space) leads to crowding and increased competition for limited resources (Stanila 2009, p. 45). Sonoyta mud turtles in dry or low surface water reaches will burrow in channels to escape desiccation for a short period of time. However, the ability of Sonoyta mud turtles to estivate may depend on behavioral cues provided by the level of permanence of water they reside in (Ligon and Stone 2003, p. 753; Stanila 2009, p. 45). After time, burrows themselves may become too dry; turtles will lose fat reserves due to lack of foraging opportunity; females may not have viable eggs due to lack of nutrition and fat reserves, thereby reducing reproduction; and eventually turtles will die from either starvation or desiccation. If water is not reliably present all year and absent beyond the dry season, turtles are not able to forage; may not reproduce; and, as drought periods lengthen, may eventually desiccate (Stanila 2009, p. 45).

Sonora mud turtles that live in permanent bodies of water have shown highly aquatic behavior with little terrestrial behavior or movement between water sources, while Sonora mud turtles in more ephemeral habits have been documented moving through or out of dry stream beds to reach wetted pools, for winter hibernation, or for estivation during drought as a drought-survival strategy (Hall and Steidl, 2007, pp. 406-408; Hensley et al. 2010, pp. 181-182; Ligon and Stone 2003, pp. 752-753; Stone 2001, pp. 46-51). Prolonged and recurrent estivation is expected to reduce fitness and increase mortality (Peterson and Stone 2000, pp. 692-698). Variation in body size among populations of Sonora mud turtles appears to be related to water permanence, and body size was significantly larger in permanent habitats compared to intermittent and ephemeral habitats (Stanila 2009, p. 31). In permanent water sites, growth and body size are positively correlated with aquatic invertebrate abundance at a site (Rosen and Lowe 1996, pp. 33, 35).

Reduced surface water and ground water reduce the survival and growth of vegetation in the riparian areas. Reductions in riparian habitat decrease subsurface moisture needed for nesting sites; drought refuge for hatchlings, juvenile, and adult turtles; and shelter from large flooding events for hatchlings, juveniles, and adults. It is likely that only adults will be the most resistant to severe droughts. Decreased riparian vegetation will lead to deterioration of the microclimate that provides soil moisture for nest sites and burrows.

Water permanence may also affect the diversity of aquatic invertebrate prey available for mud turtles, with ephemeral habitats having lower diversity than intermittent or perennial habitats (Stanila 2009, p. 38), in addition to the presence of nonnative aquatic species that compete for prey. When invertebrates are abundant, and competition is low, turtles grow rapidly and have sufficient lipid content to support reproduction. Turtle recruitment is likely driven in significant part by invertebrate prey available because nutritional stress on females may result in a reduction in annual survivorship (Rosen and Lowe 1996, p. 41). Competition from nonnatives could decrease the type and amount of aquatic invertebrate prey available to Sonoyta mud turtles (Fernandez and Rosen 1996, pp. 39-40) and lead to lower fitness of turtles. Because high average annual juvenile survivorship is required for populations of long-lived organisms to maintain population stability (Congdon et al. 1993, pp. 831-832; Congdon et al. 1994, pp. 405-406), nonnative predators that reduce recruitment in Sonoyta mud turtle populations likely cause population declines.

The current prognosis of climate change impacts on the Sonoran Desert includes fewer frost days; warmer temperatures; greater water demand by plants, animals, and people; and an increased frequency of extreme weather events (heat waves, droughts, and floods) (Weiss and Overpeck 2005, p. 2074; Archer and Predick 2008, p. 24). Any reductions in annual rainfall, coupled with the hotter temperatures that are projected with very high confidence (and that will alone bring reductions in aquifer inputs due to higher evaporation rates), would have negative effects on aquifers across the Southwest. Virtually any plausible future climate scenario projects longer dry spells between rains, which can have more severe impacts on the landscape, especially in spring and summer (Lenart 2008, entire).

Currently, five known populations of Sonoyta mud turtle remain. The perennial water supporting four of the five turtle extant populations has been reduced, and all five populations are isolated from one another. For the sole population in the United States, discharge from Quitobaquito Springs has diminished by 42 percent over the past 35 years, with 5,500 cubic feet (cf)/day average discharge measured in the period 1981-1992, down to 3,157 cf/day measured from 2005-present (Carruth 1996, pp. 13, 21; Holm 2016, pers. comm.). Thus far, declining spring flow has been associated with less than 30 centimeters (cm) (12 inches (in)) of surface water level decline at the pond, the depth of which ranges from 81 to 94 cm (32 to 37 in). This could indicate that current lower water levels of the pond are also caused by leakage or evapotranspiration, not just reduced spring flow. Excluding young-of-the-year (< 40 mm (1.6 in) carapace length), population estimates since 1984 ranged from a low of 39 turtles in 2005 to a high of 189 in 2013 with an average annual population estimate of 110 turtles. The population estimate for 2015 was 141 turtles.

In Mexico, the two populations in the Xochimilco and Papalote reaches of the Rio Sonoyta are isolated from one another even more than they used to be historically because the lengths of the perennial reaches have contracted. Added to this, a previously extant population in the Santa Domingo reach that was located between Xochimilco and Papalote reaches is no longer extant due to a complete lack of perennial water. The perennial waters in these three reaches have decreased by 80 to 92 percent from 19-27 km (11.8-16.8 mi) historically to approximately 1.5-5.5 km (0.9-3.4 mi) currently (table 1 and figure 3.1.1 of the SSA Report). Periodic movement between populations in the Rio Sonoyta basin may occur during prolonged periods of high rainfall, but the extent of immigration and emigration of turtles is unknown. However, it is thought to be rare to limited due to distances between populations coupled with limited hydrological connection.

Currently, the status of the Xochimilco population is unknown, but abundance is almost certainly far less, considering the reduced spatial and temporal extent of surface water. A total of 57 turtles have been marked in the Papalote reach in 2017, for a mark-recapture study that will provide better information on the status of the Sonoyta mud turtle in this reach in the next few years.

The population at the Sonoyta sewage lagoon adjacent to the Rio Sonoyta has the most reliable source of water at this time and may be the largest of the five populations based on water availability, but we have no current data on numbers of turtles at this site. If a new wastewater treatment plant is completed for the town of Sonoyta, the existing Sonoyta sewage lagoons will be drained and the new wastewater treatment plant will have 75 percent less habitat available for Sonoyta mud turtles. The fourth population in Mexico at Quitovac is outside of the Rio Sonoyta watershed, in the Rio Guadalupe basin, and has no present-day hydrological connection to the Rio Sonoyta. In addition, the Quitovac site was just recently completely dredged and the current status of Sonoyta mud turtles at that location is unknown.

The future resiliency of Sonoyta mud turtle populations depends on future water quantity, available riparian habitat, available invertebrate prey, and absence of certain nonnative aquatic species. In addition, if the new wastewater treatment plant becomes operational and replaces the Sonoyta sewage lagoons, this will be a reduction in water and riparian habitat for the Sonoyta mud turtle. Further, only a portion of the Sonoyta mud turtles are likely to be transplanted. Because there is uncertainty regarding how and when surface water loss and associated riparian habitat impairment may occur, as well as if and when various nonnative species may occur, we projected what the effects to the Sonoyta mud turtle may be in terms of population resiliency and species redundancy and representation under three plausible future scenarios over three meaningful time frames: 7 years, 35 years, and 70 years. We chose 7 years based on the area's drought cycle, 35 years because it incorporates both the maximum life span of the species and the mid-century climate projections for the southwestern United States, and 70 years because it is within the range of the available drought and climate change model forecasts and is about twice the maximum life span of the species (Lenart 2008, entire; Strittholt et al. 2012, entire; Garfin et al. 2013, entire).

Since surface water availability limits the other elements and the carrying capacity of the site, the ranking of the surface water was weighted higher than the other metrics. This means that if surface water was ranked moderate and all other elements were ranked high, the overall ranking would be moderate. We are presenting the moderate case scenarios, as we have determined that this is the most likely future scenario based on our understanding of the future conditions of climate change and groundwater pumping.

In preparing this final rule, we reviewed and fully considered comments we received from the public and peer reviewers on the SSA Report and proposed rule. We received numerous comments and new information from peer reviewers on the science and analysis in the SSA Report, and we have updated the SSA Report to incorporate these accordingly. In addition, we met with the National Park Service (NPS) to discuss the SSA Report, and we updated the SSA Report with the information NPS provided. This final rule incorporates minor changes to our proposed listing based on the comments we received, as discussed below in Summary of Comments and Recommendations. We received multiple comments from peer reviewers that we underestimated some of the future risks to Sonoyta mud turtle populations. We have reevaluated the viability of the Sonoyta mud turtle in the SSA Report given this new information. These data allowed us to refine our risk assessment; thus, the final results are slightly different from those in the proposed rule. We found the probability of persistence lower than in the proposed rule. The new information we received in response to the proposed rule did not change our determination that the Sonoyta mud turtle is an endangered species, nor was it significant enough to warrant reopening the public comment period on the proposed rule.

In the proposed rule published on September 21, 2016 (81 FR 64829), we requested that all interested parties submit written comments on the proposal by November 21, 2016. We also contacted appropriate Federal and State agencies, scientific experts and organizations, and other interested parties and invited them to comment on the proposal. Newspaper notices inviting general public comment were published in the Arizona Daily Star. We did not receive any requests for a public hearing.

We reviewed all comments we received in response to the proposed rule for substantive issues and new information. We did not receive any comments from Federal agencies, States, or Tribes, and the public comments we received only stated a preference for listing or not listing the subspecies without including any substantive comments regarding the sufficiency of our analysis. All substantive information provided by peer reviewers during the comment period has either been incorporated directly into this final determination or is addressed below.

In accordance with our peer review policy published on July 1, 1994 (59 FR 34270), we solicited expert opinion from eight knowledgeable individuals with scientific expertise that included familiarity with the Sonoyta mud turtle and its habitat, biological needs, and threats, or the nominate subspecies Sonora mud turtle. We received responses from six of the peer reviewers.

We reviewed all comments received from the peer reviewers for substantive issues and new information regarding the listing of Sonoyta mud turtle. The peer reviewers generally concurred with our methods and conclusion, and provided additional and pertinent information, clarifications, and suggestions to improve the SSA Report and, therefore, the final rule. Peer reviewer comments are addressed in the following summary and incorporated into the SSA Report and this final rule as appropriate.

(1) Comment: One peer reviewer stated that the new wastewater treatment facility is not constructed, nor are there in-place plans to populate it, and there is currently no guarantee that whatever habitat is constructed will actually be suitable.

Our Response: We made revisions throughout the SSA Report to acknowledge the uncertainty related to future habitat for the Sonoyta mud turtle at the new wastewater treatment plant in the town of Sonoyta, Sonora, Mexico.

(2) Comment: One peer reviewer identified the importance of stipulating that the historical range and populations of the Sonoyta mud turtle are only those that are known or have been documented.

Our Response: We acknowledge that these are only the known populations of the Sonoyta mud turtle. While historically there could have been other populations, the best available commercial and scientific information does not indicate any other additional populations.

(3) Comment: One peer reviewer stated that he is not convinced that development of Sonoyta mud turtle embryos takes 80 days and is delayed after the eggs are laid, as stated in Ernst and Lovich (2009, p. 497).

Our Response: We acknowledge uncertainty regarding the timing of embryo development, or diapause, in the Sonoyta mud turtle. However, these specific steps in the reproductive process are also noted in van Lobel Sels et al. (1997, p. 497) and Stone et al. (2015, p. 735). The best available commercial and scientific information indicates that diapause likely occurs in this subspecies as it does in the nominate subspecies.

(4) Comment: One peer reviewer stated that we are assuming that Sonoyta mud turtles need riparian areas with moist soil.

Our Response: We acknowledge uncertainty around the terrestrial habitat needs of the Sonoyta mud turtle. However, we have high confidence that this subspecies uses areas with more shade and increased soil moisture to prevent desiccation of eggs in nest sites and turtles in estivation sites. Without suitable soil moisture, eggs will desiccate, and while the threshold is unknown, at some point the loss of soil moisture will impact egg survival. In the extremely arid environment where the Sonoyta mud turtle exists, riparian areas provide more shade and soil moisture than the surrounding uplands and, therefore, provide better habitat for nests.

(5) Comment: One peer reviewer stated that some nonnative aquatic species can be both predator and competitor to the Sonoyta mud turtle, and that not all nonnatives are harmful to the Sonoyta mud turtle.

Our Response: In the SSA Report, we clarified that only certain nonnative aquatic species are predators of the Sonoyta mud turtle, and we identify those that are a potential threat. We also clarified that only certain other nonnative aquatic species, as well as native fish species, may compete with Sonoyta mud turtles for invertebrate prey or disrupt the prey food chain. Further, we clarified the effects to the Sonoyta mud turtle from predation and competition from these specific nonnatives.

(6) Comment: Multiple peer reviewers thought that our viability projections for the Sonoyta mud turtle in chapter 5 of the SSA Report were overly optimistic based on uncertainty of the current status of populations in Mexico and because we underestimated the threats of introduction of nonnative aquatic species and climate change to the subspecies. Conversely, one peer reviewer thought we overestimated the threat of nonnatives persisting at Quitobaquito Springs because NPS would probably remove the threat.

Our Response: We agree that viability projections for the Sonoyta mud turtle were overly optimistic because of the high uncertainty of the number of turtles in the Mexico populations and that we underestimated some of the threats, such as long-term drought, nonnatives, and loss of connectivity, to the Sonoyta mud turtle. We modified the SSA Report accordingly. We also agree that the nonnatives at Quitobaquito Springs have been removed by NPS in the past; however, no mechanism ensures that changing resource priorities and funding constraints will not be an issue in the future. We have modified the SSA Report accordingly.

(7) Comment: Several peer reviewers noted that statements in the SSA Report that require citations to support them. For example, one peer reviewer believed that the statement “prolonged and recurrent estivation will reduce fitness and increase mortality” was entirely speculative. Similarly, another peer reviewer indicated the uncertainties acknowledged in the SSA Report reduce its predictive value (e.g., effects of transitioning to the new sewage treatment plant, likelihood of introduction of nonnative species, status of the turtle on Tohono O'odham Nation lands, long-term genetic viability, and continued ability of State and Federal agencies to manage for this species).

Our Response: We revised the SSA Report to add citations to support statements where needed throughout the document. We also recognize that the SSA Report contains uncertainties, and throughout the document we identify these uncertainties as well as quantify or clarify our level of uncertainty. However, because we are required by the Act (16 U.S.C. 1531 et seq.) to complete this determination based on the best available scientific and commercial information, we must move forward without resolving all potential uncertainties.

(8) Comment: One peer reviewer noted that the distribution map on page 4, figure 2.1.1., of the SSA Report is a bit out of date. Specifically, the Quitovac locality is not shown, and there are now many more localities in northeastern Sonora (see the Madrean Archipelago Biodiversity Assessment and Madrean Discovery Expeditions databases).

Our Response: Figure 2.1.1. in the SSA Report is used to demonstrate the general distribution of the two mud turtle subspecies, Sonora and Sonoyta, in relation to each other, not to delineate the current range or distribution of either subspecies.

We received only comments stating a preference for listing or not listing the subspecies. We did not receive any substantive comments regarding the sufficiency of the analysis.

Section 4 of the Act (16 U.S.C. 1533), and its implementing regulations at 50 CFR part 424, set forth the procedures for adding species to the Federal Lists of Endangered and Threatened Wildlife and Plants. Under section 4(a)(1) of the Act, we may list a species based on (A) The present or threatened destruction, modification, or curtailment of its habitat or range; (B) Overutilization for commercial, recreational, scientific, or educational purposes; (C) Disease or predation; (D) The inadequacy of existing regulatory mechanisms; or (E) Other natural or manmade factors affecting its continued existence. Listing actions may be warranted based on any of the above threat factors, singly or in combination.

The fundamental question before the Service is whether the species meets the definition of “endangered species” or “threatened species” under the Act. To make this determination, we evaluated the projections of extinction risk, described in terms of the condition of current and future populations and their distribution (taking into account the risk factors and their effects on those populations). For any species, as population condition declines and distribution shrinks, the species' extinction risk increases and overall viability declines.

We have carefully assessed the best scientific and commercial information available regarding the past, present, and future threats to the Sonoyta mud turtle. Currently, the five extant populations are all significantly isolated from one another such that recolonization of areas previously extirpated or areas that may be extirpated is extremely unlikely. Expert input provided during the development of the SSA Report indicated that connectivity or movement among the populations is a rare or nonexistent occurrence. The species' range has been reduced by 80 to 92 percent in the Rio Sonoyta (Factor A) in Mexico, and current distribution is limited to five populations in three ponds totaling less than 7 ha (less than 17.5 ac) and two perennial sections of the Rio Sonoyta totaling 1.5 to 5.5 km (0.9 to 3.4 mi). Two historical populations are extirpated due to loss of perennial water. There are two newly discovered extant populations in addition to the three historical populations that remain. One is within a wastewater treatment plant where the impacts from facility management and water quality make monitoring difficult and may be adverse to Sonoyta mud turtle viability, and the other is outside the Rio Sonoyta basin, which is likely outside the historical range of the species. None of the five populations are classified as having “high” resiliency, described in the SSA Report as “all or the majority of turtles are able to complete their life functions and breeding is successful to maintain a stable or increasing population, and able to withstand stochastic events or recover from stochastic events from connected populations.” Even with a resiliency classified as “moderate” in three populations, we expect stable or decreasing populations that are not able to recover from stochastic events. The remaining two populations have few turtles able to complete life functions, a decreasing population, and inability to withstand or recover from stochastic events. All five of these populations are currently facing stressors and are susceptible to current and ongoing impacts.

Habitat loss from anthropogenic ground water withdrawals and long-term drought is occurring rangewide and is likely to continue and increase in the near term (Factors A and E). This reduction in water restricts the limited available habitat and decreases the resiliency of Sonoyta mud turtle populations within those habitats. We find that ongoing cyclical drought is likely to continue and be exacerbated by climate change, further decreasing water availability and increasing evapotranspiration losses (Factors A and E). This threat is ongoing, rangewide, and expected to increase in the future. Predation by nonnative aquatic species has occurred at two sites in Mexico, although there is uncertainty with regard to the population effects (Factor C). Predation by nonnative aquatic species reduces recruitment and population size of populations of Sonora mud turtle, and it is likely to continue to affect Sonoyta mud turtle populations in the future. The Quitovac population's current habitat was just recently completely dredged (Factor A), and the current status of Sonoyta mud turtles at that location is unknown. Partial dredging in the near term is likely to occur based on past dredging activity. It is reasonably likely that a catastrophic event could occur imminently at one or more of the population sites, and current population resiliency and redundancy are inadequate to maintain population viability.

The implementation of the conservation measures by NPS and the Quitobaquito Rio Sonoyta Working Group has resulted in maintaining the only Sonoyta mud turtle population in the United States and reduces the risk of loss of at least one population in Mexico. However, the conservation measures do not alleviate the threats that are influencing the resiliency, redundancy, and representation of the Sonoyta mud turtle across its range (as described above).

The Act defines a “species” as including any “subspecies of fish or wildlife or plants, and any distinct population segment of any species of vertebrate fish or wildlife which interbreeds when mature.” The Act defines an “endangered species” as any species that is “in danger of extinction throughout all or a significant portion of its range” and a “threatened species” as any species “that is likely to become endangered throughout all or a significant portion of its range within the foreseeable future.” Based on the information presented in the SSA Report for the Sonoyta mud turtle, and the discussion above, we find that the best available scientific and commercial information indicates that the Sonoyta mud turtle is presently in danger of extinction throughout its entire range based on the severity and immediacy of threats currently impacting the subspecies. The overall range has been significantly reduced; the limited remaining habitat and populations are currently threatened by an increase in ground water pumping, which results in reduced spring flows and, therefore, reduced surface water. Discharge from Quitobaquito Springs has diminished by 42 percent over the past 35 years, and the pond depth has been declining since the early 1990s due to evapotranspiration, leakage, and the reduction in spring water discharge. The perennial waters in the three historical reaches of the Rio Sonoyta have decreased by 80 to 92 percent. Current distribution is limited to five populations in three ponds totaling less than 7 ha (less than 17.5 ac) and two perennial sections of the Rio Sonoyta totaling 1.5 to 5.5 km (0.9 to 3.4 mi). The new wastewater treatment plant, if utilized, will provide 75 percent less habitat available for Sonoyta mud turtles than the current sewage lagoon. Reduced surface water results in reduced aquatic habitat where the subspecies spends the majority of its time and that is needed to avoid desiccation of all life stages. Further, the reduction in surface water impacts aquatic vegetation used by the Sonoyta mud turtle for cover and by its prey species. Lastly, the reduction in ground water reduces the soil moisture of the riparian area, resulting in habitat that is too dry for Sonoyta mud turtles to use for estivation and nesting.

These factors, acting in combination, reduce the overall viability of the subspecies. Each of the five remaining populations are exposed to threats that may eliminate them individually at any time. The risk of extinction for this subspecies is currently high because the five remaining populations are small, isolated, and have limited (if any) potential for recolonization. Each population's isolation from other populations means that once a population is extirpated, it is likely to remain extirpated. The estimated current conditions of the known Sonoyta mud turtle populations as described in the SSA Report lead us to find that the condition and distribution of populations do not provide sufficient resiliency, redundancy, and representation for this subspecies at this time; therefore, we find that the subspecies meets the definition of an endangered species under the Act. Accordingly, on the basis of the best available scientific and commercial information, we are listing the Sonoyta mud turtle as endangered in accordance with sections 3(6) and 4(a)(1) of the Act.

We find that a threatened status is not appropriate for the Sonoyta mud turtle because the danger of extinction for this subspecies exists now. The current restricted range and ubiquitous and imminent threats occur rangewide. Consequently, we find the Sonoyta mud turtle to be in danger of extinction now throughout its range.

The Act defines an endangered species as any species that is “in danger of extinction throughout all or a significant portion of its range” and a threatened species as any species “that is likely to become endangered within the foreseeable future throughout all or a significant portion of its range.” The phrase “significant portion of its range” is not defined by the Act, and a district court has held that aspects of the Service's Final Policy on Interpretation of the Phrase “Significant Portion of Its Range” in the Endangered Species Act's Definitions of “Endangered Species and “Threatened Species” (79 FR 37577 (July 1, 2014)) (SPR Policy) were not valid. Center for Biological Diversity v. Jewell, No. 14-cv-02506-RM (D. Ariz. Mar. 29, 2017) (Pygmy-Owl Decision).

Although the court's order in that case has not yet gone into effect, if the court denies the pending motion for reconsideration, the SPR Policy would become vacated. Therefore, we have examined the plain language of the Act and court decisions addressing the Service's application of the SPR phrase in various listing decisions, and for purposes of this rulemaking we are applying the interpretation set out below for the phrase “significant portion of its range” and its context in determining whether or not a species is an endangered species or a threatened species. Because the interpretation we are applying is consistent with the SPR Policy, we summarize herein the bases for our interpretation, and also refer the public to the SPR Policy itself for a more-detailed explanation of our reasons for interpreting the phrase in this way.

An important factor that influences the question of whether an SPR analysis is necessary here is what the consequence would be if the Service were to find that the Sonoyta mud turtle is in danger of extinction or likely to become so throughout a significant portion of its range. Two district court decisions have evaluated whether the outcomes of the Service's SPR determinations were reasonable. As described in the SPR Policy, both courts found that, once the Service determines that a “species”—which can include a species, subspecies, or DPS under ESA Section 3(16)—meets the definition of “endangered species” or “threatened species,” the species must be listed in its entirety and the Act's protections applied consistently to all members of that species (subject to modification of protections through special rules under sections 4(d) and 10(j) of the Act). See Defenders of Wildlife v. Salazar, 729 F. Supp. 2d 1207, 1222 (D. Mont. 2010) (delisting of the Northern Rocky Mountains DPS of gray wolf; appeal dismissed as moot because of public law vacating the listing, 2012 U.S. App. LEXIS 26769 (9th Cir. Nov. 7, 2012)); WildEarth Guardians v. Salazar, No. 09-00574-PHX-FJM, 2010 U.S. Dist. LEXIS 105253, 15-16 (D. Ariz. Sept. 30, 2010) (Gunnison's prairie dog). The issue has not been addressed by a Federal Court of Appeals.

Consistent with the district court case law, we interpret that the consequence of finding that the Sonoyta mud turtle is in danger of extinction or likely to become so throughout a significant portion of its range would be that the entire species would be listed as an endangered species or threatened species, respectively, and the Act's protections would be applied to all individuals of the species wherever found. Thus, the “throughout all” phrase and the SPR phrase provide two independent bases for listing. We note that in the Act Congress placed the “all” language before the SPR phrase in the definitions of “endangered species” and “threatened species.” This suggests that Congress intended that an analysis based on consideration of the entire range should receive primary focus. Thus, the first step we undertook, above, in our assessment of the status of the species was to determine its status throughout all of its range. Having determined that the species is in danger of extinction throughout all of its range, we now examine whether it is necessary to determine its status throughout a significant portion of its range.

We conclude that in this situation we do not need to conduct an SPR analysis. This conclusion is consistent with the Act because the species is currently in danger of extinction throughout all of its range due either to high-magnitude threats across its range, or to threats that are so high in particular areas that they severely affect the species across its range. Therefore, the species is in danger of extinction throughout every portion of its range, and an analysis of whether the species is in danger of extinction or likely to become so throughout any significant portion of its range would be redundant and unnecessary. We accordingly conclude that we do not need to conduct further analysis of whether the Sonoyta mud turtle is in danger of extinction or likely to become so in the foreseeable future throughout a significant portion of its range.

Therefore, on the basis of the best available scientific and commercial information, we are adding Sonoyta mud turtle to the List of Endangered and Threatened Wildlife as an endangered species in accordance with sections 3(6) and 4(a)(1) of the Act. We find that a threatened species status is not appropriate for Sonoyta mud turtle because of the immediacy of threats facing the species with only five known populations, at least one of which is declining in abundance.

Section 4(a)(3) of the Act, as amended, and implementing regulations (50 CFR 424.12), require that, to the maximum extent prudent and determinable, the Secretary shall designate critical habitat at the time the species is determined to be an endangered or threatened species. Our regulations (50 CFR 424.12(a)(1)) state that the designation of critical habitat is not prudent when one or both of the following situations exist:

(1) The species is threatened by taking or other human activity, and identification of critical habitat can be expected to increase the degree of threat to the species, or

(2) Such designation of critical habitat would not be beneficial to the species. In determining whether a designation would not be beneficial, the factors the Service may consider include but are not limited to: Whether the present or threatened destruction, modification, or curtailment of a species' habitat or range is not a threat to the species, or whether any areas meet the definition of “critical habitat.”

There is currently no imminent threat of take attributed to collection or vandalism identified under Factor B for this subspecies, and identification and mapping of critical habitat is not expected to initiate any such threat. In the absence of finding that the designation of critical habitat would increase threats to a species, we next determine whether such designation of critical habitat would not be beneficial to the species. In our proposed listing rule, we determined that there are habitat-based threats to the Sonoyta mud turtle identified under Factor A. Therefore, we find that the designation of critical habitat would be beneficial to Sonoyta mud turtle through the provisions of section 7 of the Act. Because we have determined that the designation of critical habitat will not likely increase the degree of threat to the subspecies and would be beneficial, we find that designation of critical habitat is prudent for the Sonoyta mud turtle.

Having determined that designation is prudent, under section 4(a)(3) of the Act, we must find whether critical habitat for the Sonoyta mud turtle is determinable. Our regulations at 50 CFR 424.12(a)(2) state that critical habitat is not determinable when one or both of the following situations exist:

(i) Information sufficient to perform required analysis of the impacts of the designation is lacking, or

(ii) The biological needs of the species are not sufficiently well known to identify any area that meets the definition of “critical habitat.”

As required by section 4(b)(2) of the Act, we use the best scientific data available to designate critical habitat after taking into consideration the economic impact, national security impact, and any other relevant impact of specifying any particular area as critical habitat. In accordance with the Act and our implementing regulations at 50 CFR 424.12(b), we review available information pertaining to the habitat requirements of the species and identify specific areas within the geographical area occupied by the species at the time of listing and any specific areas outside the geographical area occupied by the species to be considered for designation as critical habitat. A careful assessment of the economic impacts that may occur due to a critical habitat designation is still ongoing, and we are in the process of working with Customs and Border Protection and the National Park Service in acquiring the necessary information needed to perform that assessment. The information sufficient to perform a required analysis of the impacts of the designation is lacking. Accordingly, we find that critical habitat for this subspecies, in accordance with section 4(a)(3)(A) of the Act, to be not determinable at this time. When critical habitat is not determinable, the Act allows the Service an additional year to publish a critical habitat designation (16 U.S.C. 1533(b)(6)(C)(ii)).

Conservation measures provided to species listed as endangered or threatened species under the Act include recognition, recovery actions, requirements for Federal protection, and prohibitions against certain practices. Recognition through listing results in public awareness, and conservation by Federal, State, Tribal, and local agencies, private organizations, and individuals. The Act encourages cooperation with the States and requires that recovery actions be carried out for all listed species. The protection required by Federal agencies and the prohibitions against certain activities are discussed, in part, below.

The primary purpose of the Act is the conservation of endangered and threatened species and the ecosystems upon which they depend. The ultimate goal of such conservation efforts is the recovery of these listed species, so that they no longer need the protective measures of the Act. Subsection 4(f) of the Act requires the Service to develop and implement recovery plans for the conservation of endangered and threatened species. The recovery planning process involves the identification of actions that are necessary to halt or reverse the species' decline by addressing the threats to its survival and recovery. The goal of this process is to restore listed species to a point where they are secure, self-sustaining, and functioning components of their ecosystems.

Recovery planning includes the development of a recovery outline shortly after a species is listed and preparation of a draft and final recovery plan. The recovery outline guides the immediate implementation of urgent recovery actions and describes the process to be used to develop a recovery plan. Revisions of the plan may be done to address continuing or new threats to the species, as new substantive information becomes available. The recovery plan identifies site-specific management actions that set a trigger for review of the five factors that control whether a species remains endangered or may be downlisted or delisted, and methods for monitoring recovery progress. Recovery plans also establish a framework for agencies to coordinate their recovery efforts and provide estimates of the cost of implementing recovery tasks. Recovery teams (composed of species experts, Federal and State agencies, nongovernmental organizations, and stakeholders) are often established to develop recovery plans. When completed, the recovery outline, draft recovery plan, and the final recovery plan will be available on our Web site (http://www.fws.gov/endangered) or from our Arizona Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).

Implementation of recovery actions generally requires the participation of a broad range of partners, including other Federal agencies, States, Tribes, nongovernmental organizations, businesses, and private landowners. Examples of recovery actions include habitat restoration (e.g., restoration of native vegetation), research, captive propagation and reintroduction, and outreach and education. The recovery of many listed species cannot be accomplished solely on Federal lands because their range may occur primarily or solely on non-Federal lands. To achieve recovery of these species requires cooperative conservation efforts on private, State, and Tribal lands.

Following publication of this final listing rule, funding for recovery actions will be available from a variety of sources, including Federal budgets, State programs, and cost share grants for non-Federal landowners, the academic community, and nongovernmental organizations. In addition, pursuant to section 6 of the Act, the State of Arizona will be eligible for Federal funds to implement management actions that promote the protection or recovery of the Sonoyta mud turtle. Information on our grant programs that are available to aid species recovery can be found at: http://www.fws.gov/grants.

Please let us know if you are interested in participating in recovery efforts for the Sonoyta mud turtle. Additionally, we invite you to submit any new information on this subspecies whenever it becomes available and any information you may have for recovery planning purposes (see FOR FURTHER INFORMATION CONTACT).

Section 7(a) of the Act requires Federal agencies to evaluate their actions with respect to any species that is listed as an endangered or threatened species and with respect to its critical habitat, if any is designated. Regulations implementing this interagency cooperation provision of the Act are codified at 50 CFR part 402. Section 7(a)(2) of the Act requires Federal agencies to ensure that activities they authorize, fund, or carry out are not likely to jeopardize the continued existence of any endangered or threatened species or destroy or adversely modify its critical habitat. If a Federal action may affect a listed species or its critical habitat, the responsible Federal agency must enter into consultation with the Service.

Federal agency actions within the subspecies' habitat that may require conference or consultation or both as described in the preceding paragraph include management and any other landscape-altering activities on Federal lands administered by NPS (Organ Pipe Cactus National Monument) and U.S. Customs and Border Protection.

The Act and its implementing regulations set forth a series of general prohibitions and exceptions that apply to endangered wildlife. The prohibitions of section 9(a)(1) of the Act, codified at 50 CFR 17.21, make it illegal for any person subject to the jurisdiction of the United States to take (which includes harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect; or to attempt any of these) endangered wildlife within the United States or on the high seas. In addition, it is unlawful to import; export; deliver, receive, carry, transport, or ship in interstate or foreign commerce in the course of commercial activity; or sell or offer for sale in interstate or foreign commerce any listed species. It is also illegal to possess, sell, deliver, carry, transport, or ship any such wildlife that has been taken illegally. Certain exceptions apply to employees of the Service, the National Marine Fisheries Service, other Federal land management agencies, and State conservation agencies.

We may issue permits to carry out otherwise prohibited activities involving endangered wildlife under certain circumstances. Regulations governing permits are codified at 50 CFR 17.22. With regard to endangered wildlife, a permit may be issued for the following purposes: for scientific purposes, to enhance the propagation or survival of the species, and for incidental take in connection with otherwise lawful activities. There are also certain statutory exemptions from the prohibitions, which are set forth at sections 9 and 10 of the Act.

It is our policy, as published in the Federal Register on July 1, 1994 (59 FR 34272), to identify to the maximum extent practicable at the time a species is listed, those activities that would or would not constitute a violation of section 9 of the Act. The intent of this policy is to increase public awareness of the effect of a final listing on proposed and ongoing activities within the range of a listed species. At this time, we are unable to identify specific activities that would not be considered to result in a violation of section 9 of the Act because the Sonoyta mud turtle sites where the species currently occurs are subject to a variety of potential activities, and it is likely that site-specific conservation measures may be needed for activities that may directly or indirectly affect the species. Based on the best available information, the following actions are likely to result in a violation of section 9; this list is not comprehensive:

(1) Unauthorized handling or collecting of the Sonoyta mud turtle.

(2) Destruction/alteration of Sonoyta mud turtle habitat by discharge of fill material, draining, ditching, tiling, pond construction, stream channelization or diversion, removal or destruction of emergent aquatic vegetation; or diversion or alteration of surface or ground water flow into or out of the wetland (i.e., due to roads, impoundments, discharge pipes, storm water detention basins, etc.) or in any body of water in which the Sonoyta mud turtle is known to occur.

(3) Direct or indirect destruction of riparian habitat.

(4) Introduction of nonnative species that compete with or prey upon the Sonoyta mud turtle, such as the introduction of nonnative fish and crayfish species.

(5) Release of biological control agents that attack any life stage of this subspecies.

(6) Discharge of chemicals or fill material into any waters in which the Sonoyta mud turtle is known to occur.

Questions regarding whether specific activities would constitute a violation of section 9 of the Act should be directed to the Arizona Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).

We have determined that environmental assessments and environmental impact statements, as defined under the authority of the National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), need not be prepared in connection with listing a species as an endangered or threatened species under the Endangered Species Act. We published a notice outlining our reasons for this determination in the Federal Register on October 25, 1983 (48 FR 49244).

In accordance with the President's memorandum of April 29, 1994 (Government-to-Government Relations with Native American Tribal Governments; 59 FR 22951), Executive Order 13175 (Consultation and Coordination With Indian Tribal Governments), and the Department of the Interior's manual at 512 DM 2, we readily acknowledge our responsibility to communicate meaningfully with recognized Federal Tribes on a government-to-government basis. In accordance with Secretarial Order 3206 of June 5, 1997 (American Indian Tribal Rights, Federal-Tribal Trust Responsibilities, and the Endangered Species Act), we readily acknowledge our responsibilities to work directly with tribes in developing programs for healthy ecosystems, to acknowledge that tribal lands are not subject to the same controls as Federal public lands, to remain sensitive to Indian culture, and to make information available to tribes.

Based on cultural claims maps and reservation boundaries we have on file, the distribution of the Sonoyta mud turtle overlaps areas that may be of interest to the following tribes: Tohono O'odham Nation, Quechan Tribe, Hopi Tribe, Colorado River Indian Tribes, and Cocopah Indian Tribe. On November 20, 2015, we notified these tribes via letter of our intent to conduct a status assessment for the purpose of determining whether the subspecies warrants protection under the Act. In our letter, we offered to meet with the tribe to discuss the process, potential impacts to the tribes, and how tribal information may be used in our assessment. In addition, we requested any information they have regarding the subspecies. On August 17, 2016, we invited comments from the five tribes, and on September 19, 2016, we submitted notification to tribal leaders of the proposed listing publication. To date, we have not received a response from these any of these tribes. Upon publication of this final rule, we will send notification letters to these tribes and again extend an invitation to meet and discuss.

A complete list of references cited in this rulemaking is available in the SSA Report (U.S. Fish and Wildlife Service 2017. Species status assessment report for the Sonoyta mud turtle (Kinosternon sonoriense longifemorale), Version 2.0. Albuquerque, NM) that is available on the Internet at http://www.regulations.gov at Docket Number FWS-R2-ES-2016-0103, at https://www.fws.gov/southwest/es/arizona/, and upon request from the Arizona Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).

The primary authors of this final rule are the staff members of the Arizona Ecological Services Field Office.

Accordingly, we amend part 17, subchapter B of chapter I, title 50 of the Code of Federal Regulations, as follows:

NMFS and the Western Pacific Fishery Management Council (Council) manage pelagic fisheries in the U.S. Pacific Islands under the Fishery Ecosystem Plan for Pelagic Fisheries of the Western Pacific Region, formerly the Fishery Management Plan for Pelagic Fisheries of the Western Pacific Region (FMP). In 2002, in response to a recommendation from the Council, NMFS implemented a measure under the FMP that prohibited certain vessels from fishing for Pacific pelagic management unit species in Federal waters from 3 nm to approximately 30-50 nm around the islands of American Samoa (the Large Vessel Prohibited Area, LVPA). The area prohibition applied to vessels more than 50 ft in length overall that had not landed pelagic management unit species in American Samoa under a Federal longline general permit prior to November 13, 1997. The LVPA was intended to prevent the potential for gear conflicts and catch competition between large and small vessels. At the time, the Council and NMFS felt that such conflicts and competition could have led to reduced opportunities for sustained participation by residents of American Samoa in the small-scale pelagic fishery. You may read more about the establishment of the LVPA in the 2001 proposed rule (66 FR 39475, July 31, 2001) and 2002 final rule (67 FR 4369, January 30, 2002).

Since 2002, however, the American Samoa longline fishery has been experiencing declining catch rates of albacore, lower fish prices, and increased fuel and operating costs. In the period 2001-2009, longline incomes had decreased by 96 percent, with average revenues only half of what was necessary for profitable operations. Concerned that the LVPA might be unnecessarily reducing the efficiency of the larger American Samoa longline vessels by displacing the fleet from a part of their historical fishing grounds, in early 2014 the Council began exploring ways to assist the longline fishery, while ensuring conservation of affected stocks and minimizing impacts to other fisheries. To address current fishery conditions, the Council recommended in 2015 that NMFS provide a limited exemption from the LVPA based on vessel size, and allow federally permitted U.S. longline vessels 50 ft and longer to fish in portions of the LVPA.

Accordingly, in 2016, NMFS published a final rule that allowed large federally permitted U.S. longline vessels to fish in specific areas of the LVPA. That action allowed large U.S. vessels that hold a Federal American Samoa longline limited entry permit to fish within the LVPA to within about 12-17 nm from shore around Swains Island, Tutuila, and the Manua Islands. Large vessels continued to be restricted from fishing within the remaining portions of the LVPA. The intent of the rule was to improve the viability of the American Samoa longline fishery and achieve optimum yield, while preventing overfishing in accordance with National Standard 1 of the Magnuson-Stevens Fishery Conservation and Management Act (Magnuson-Stevens Act). You may read more about the large vessel exemptions to the LVPA in the 2015 proposed rule (80 FR 51527, August 25, 2015) and 2016 final rule (81 FR 5619, February 3, 2016).

In July 2016, the Territory of American Samoa sued NMFS and the Council in the U.S. District Court for the District of Hawaii (Territory of American Samoa v. NMFS, et al. (D. HI) Civil 16-00095), seeking to set aside the 2016 final rule. The Territory claimed that NMFS did not consider, as other applicable law, the 1900 and 1904 Deeds of Cession with respect to the protection of the cultural fishing rights of the people of American Samoa.

On March 20, 2017, the U.S. District Court for the District of Hawaii held that, because NMFS did not consider whether the 2016 rule was consistent with the Deeds of Cession, the final rule was invalid. The Court issued an Order for NMFS to vacate and set aside the LVPA exemption rule. On August 10, 2017, the U.S. District Court denied Defendants' Motion for Reconsideration of this Judgment. Pursuant to the Final Judgment, this final rule removes the LVPA exemptions based on vessel size found at Title 50, Code of Federal Regulations, Section 665.818, paragraph (b). All other provisions applicable to the American Samoa longline fishery remain unchanged.

The Assistant Administrator for Fisheries, NOAA, has determined that this final rule is consistent with the Court's Final Judgment, the Magnuson-Stevens Act, and other applicable laws.

This final rule has been determined to be not significant for purposes of Executive Order 12866.

The Assistant Administrator for Fisheries, NOAA, finds good cause to waive notice and public comment on this action because it would be unnecessary and contrary to the public interest, as provided by 5 U.S.C. 553(b)(B). This action is limited in scope and ensures that the regulatory text provides accurate information to the regulated public that is consistent with a Federal Court Order. NMFS does not have discretion to take other action, as there is no alternative to complying with the requirements of the Court Order.

Furthermore, the Assistant Administrator for Fisheries finds good cause to waive the 30-day delayed effectiveness period, as provided by 5 U.S.C. 553(d)(3), finding that such delay would be contrary to the public interest because the measures contained in this rule are necessary to ensure that the fishery is conducted in compliance with a Federal Court Order. On March 27, 2017, NMFS notified longline permit holders of the Court Order, that the exemption available to large longline vessels no longer applies, and that they may not fish within the boundaries of the LVPA.

Because this rulemaking is required by Court Order, and prior notice and opportunity for public comment are not required under 5 U.S.C. 553, or any other law, the regulatory flexibility analysis requirements of the Regulatory Flexibility Act, 5 U.S.C. 603-605, do not apply to this rule. Accordingly, no regulatory flexibility analysis is required and none has been prepared.

In addition, because the changes required by the Court Order that are identified in this rule are non-discretionary, the National Environmental Policy Act does not apply to this rule.

For the reasons set out in the preamble, NMFS amends 50 CFR part 665 as follows: