80 FR 8619 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition to List Yellowtail Damselfish as Threatened or Endangered Under the Endangered Species Act

DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration

Federal Register Volume 80, Issue 32 (February 18, 2015)

Page Range8619-8627
FR Document2015-03326

We (NMFS) announce a 90-day finding on a petition to list yellowtail damselfish (Microspathodon chrysurus) as threatened or endangered under the Endangered Species Act (ESA). We find that the petition does not present substantial scientific or commercial information indicating that the petitioned action may be warranted.

Federal Register, Volume 80 Issue 32 (Wednesday, February 18, 2015)
[Federal Register Volume 80, Number 32 (Wednesday, February 18, 2015)]
[Notices]
[Pages 8619-8627]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2015-03326]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[Docket No. 130312237-5115-01]
RIN 0648-XC567


Endangered and Threatened Wildlife; 90-Day Finding on a Petition 
to List Yellowtail Damselfish as Threatened or Endangered Under the 
Endangered Species Act

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Department of Commerce.

ACTION: Notice of 90-day petition finding.

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SUMMARY: We (NMFS) announce a 90-day finding on a petition to list 
yellowtail damselfish (Microspathodon chrysurus) as threatened or 
endangered under the Endangered Species Act (ESA). We find that the 
petition does not present substantial scientific or commercial 
information indicating that the petitioned action may be warranted.

ADDRESSES: Copies of the petitions and related materials are available 
upon

[[Page 8620]]

request from the Assistant Regional Administrator, Protected Resources 
Division, Southeast Regional Office, NMFS, 263 13th Avenue South, St. 
Petersburg, FL 33701, or online at: http://sero.nmfs.noaa.gov/pr/ListingPetitions.htm.

FOR FURTHER INFORMATION CONTACT: Jason Rueter, NMFS Southeast Region, 
727-824-5312.

SUPPLEMENTARY INFORMATION: 

Background

    On September 14, 2012, we received a petition from the Center for 
Biological Diversity (CBD) to list eight reef fishes of the family 
Pomacentridae as threatened or endangered under the ESA. The eight 
species are orange clownfish (Amphiprion percula), black-axil chromis 
(Chromis atripectoralis), blue-green damselfish (Chromis viridis), 
Hawaiian dascyllus (Dascyllus albisella), reticulated damselfish 
(Dascyllus reticulatus), yellowtail damselfish or jewelfish 
(Microspathodon chrysurus), blackbar devil or Dick's damselfish 
(Plectroglyphidodon dickii), and blue-eyed damselfish 
(Plectroglyphidodon johnstonianus). The petition is available on our 
Web site (http://www.nmfs.noaa.gov/pr/species/petitions/pomacentrid_reef_fish_petition_2012.pdf). Given the geographic range of 
these species, we divided the lead for the response to the petition 
between our Southeast Regional Office (SERO) and our Pacific Islands 
Regional Office (PIRO). SERO led the response to the petition to list 
the yellowtail damselfish (Microspathodon chrysurus) in this finding; 
PIRO led the response for the remaining species separately and 
published a 90-day finding on those species on September 3, 2014 (79 FR 
52276).

ESA Statutory and Regulatory Provisions and Evaluation Framework

    Section 4(b)(3)(A) of the ESA of 1973, as amended (U.S.C. 1531 et 
seq.), requires, to the maximum extent practicable, that within 90 days 
of receipt of a petition to list a species as threatened or endangered, 
the Secretary of Commerce make a finding on whether that petition 
presents substantial scientific or commercial information indicating 
that the petitioned action may be warranted, and to promptly publish 
such finding in the Federal Register (16 U.S.C. 1533(b)(3)(A)). When we 
find that substantial scientific or commercial information in a 
petition indicates the petitioned action may be warranted (a ``positive 
90-day finding''), we are required to promptly commence a review of the 
status of the species concerned, during which we will conduct a 
comprehensive review of the best available scientific and commercial 
information. In such cases, we are to conclude the review with a 
finding as to whether, in fact, the petitioned action is warranted 
within 12 months of receipt of the petition. Because the finding at the 
12-month stage is based on a more thorough review of the available 
information, as compared to the narrow scope of review at the 90-day 
stage, a ``may be warranted'' finding at the 90-day stage does not 
prejudge the outcome of the status review.
    Under the ESA, a listing determination may address a ``species,'' 
which is defined to also include subspecies and, for any vertebrate 
species, any distinct population segment (DPS) that interbreeds when 
mature (16 U.S.C. 1532(16)). A species, subspecies, or DPS is 
``endangered'' if it is in danger of extinction throughout all or a 
significant portion of its range, and ``threatened'' if it is likely to 
become endangered within the foreseeable future throughout all or a 
significant portion of its range (ESA sections 3(6) and 3(20), 
respectively; 16 U.S.C. 1532(6) and (20)). Pursuant to the ESA and our 
implementing regulations, we determine whether species are threatened 
or endangered because of any one or a combination of the following five 
section 4(a)(1) factors: The present or threatened destruction, 
modification, or curtailment of habitat or range; overutilization for 
commercial, recreational, scientific, or educational purposes; disease 
or predation; inadequacy of existing regulatory mechanisms; and any 
other natural or manmade factors affecting the species' existence (16 
U.S.C. 1533(a)(1), 50 CFR 424.11(c)).
    ESA-implementing regulations issued jointly by NMFS and USFWS (50 
CFR 424.14(b)) define ``substantial information'' in the context of 
reviewing a petition to list, delist, or reclassify a species as the 
amount of information that would lead a reasonable person to believe 
that the measure proposed in the petition may be warranted. In 
evaluating whether substantial information is contained in a petition, 
the Secretary must consider whether the petition: (1) Clearly indicates 
the administrative measure recommended and gives the scientific and any 
common name of the species involved; (2) contains a detailed narrative 
justification for the recommended measure, describing, based on 
available information, past and present numbers and distribution of the 
species involved and any threats faced by the species; (3) provides 
information regarding the status of the species over all or a 
significant portion of its range; and (4) is accompanied by the 
appropriate supporting documentation in the form of bibliographic 
references, reprints of pertinent publications, copies of reports or 
letters from authorities, and maps (50 CFR 424.14(b)(2)).
    Court decisions clarify the appropriate scope and limitations of 
the Services' review of petitions at the 90-day finding stage to make a 
determination whether a petitioned action ``may be'' warranted. As a 
general matter, these decisions hold that a petition need not establish 
a ``strong likelihood'' or a ``high probability'' that a species is 
either threatened or endangered to support a positive 90-day finding.
    We evaluate the petitioner's request based upon the information in 
the petition, including its references, and the information readily 
available in our files. We do not conduct additional research, and we 
do not solicit information from parties outside the agency to help us 
in evaluating the petition. We will accept the petitioner's sources and 
characterizations of the information presented, if they appear to be 
based on accepted scientific principles, unless we have specific 
information in our files that indicates the petition's information is 
incorrect, unreliable, obsolete, or otherwise irrelevant to the 
requested action. Information that is susceptible to more than one 
interpretation or that is contradicted by other available information 
will not be dismissed at the 90-day finding stage, so long as it is 
reliable and a reasonable person would conclude it supports the 
petitioner's assertions. In other words, conclusive information 
indicating the species may meet the ESA's requirements for listing is 
not required to make a positive 90-day finding. We will not conclude 
that a lack of specific information alone negates a positive 90-day 
finding, if a reasonable person would conclude that the unknown 
information itself suggests an extinction risk of concern for the 
species at issue.
    To make a 90-day finding on a petition to list a species, we 
evaluate whether the petition presents substantial scientific or 
commercial information indicating the subject species may be either 
threatened or endangered, as defined by the ESA. First, we evaluate 
whether the information presented in the petition, along with the 
information readily available in our files, indicates that the 
petitioned entity constitutes a ``species'' eligible for listing under 
the ESA. Next,

[[Page 8621]]

we evaluate whether the information indicates that the species at issue 
faces extinction risk that is cause for concern; this may be indicated 
in information expressly discussing the species' status and trends, or 
in information describing impacts and threats to the species. We 
evaluate any information on specific demographic factors pertinent to 
evaluating extinction risk for the species at issue (e.g., population 
abundance and trends, productivity, spatial structure, age structure, 
sex ratio, diversity, current and historical range, or habitat 
integrity), and the potential contribution of identified demographic 
risks to extinction risk for the species. We then evaluate the 
potential links between these demographic risks and the causative 
impacts and threats identified in section 4(a)(1).
    Information presented on impacts or threats should be such that it 
reasonably suggests that one or more of these factors may be operative 
threats that act, or have acted, on the petitioned species to the point 
that it may warrant protection under the ESA. Broad statements about 
generalized threats to the species, or identification of factors that 
could negatively impact a species, do not constitute substantial 
information that listing may be warranted. We look for information 
indicating that not only is the particular species exposed to a factor, 
but that the species may be responding in a negative fashion; then we 
assess the potential significance of that negative response.
    Many petitions identify risk classifications made by other 
organizations or agencies, such as the International Union on the 
Conservation of Nature (IUCN), the American Fisheries Society (AFS), or 
NatureServe, as evidence of extinction risk for a species. Risk 
classifications by other organizations or made under other federal or 
state statutes may be informative, but the classification alone may not 
provide the rationale for a positive 90-day finding under the ESA. For 
example, as explained by NatureServe, their assessments of a species' 
conservation status do ``not constitute a recommendation by NatureServe 
for listing under the U.S. Endangered Species Act'' because NatureServe 
assessments ``have different criteria, evidence requirements, purposes 
and taxonomic coverage than government lists of endangered and 
threatened species, and therefore these two types of lists should not 
be expected to coincide'' (http://www.natureserve.org/prodServices/statusAssessment.jsp). Thus, when a petition cites such 
classifications, we will evaluate the source information that the 
classification is based upon, in light of the standards on extinction 
risk and impacts or threats discussed above.

Species Description

    The yellowtail damselfish is a reef fish (Family Pomacentridae) 
that inhabits shallow coral reefs usually at depths between 1-10 m 
(depth range can be up to 120 m; Loris and Rucabado, 1990) in the 
western Atlantic Ocean including Bermuda, southern Florida, and the 
Caribbean Sea (Allen, 1991), south to Brazil (Moura et al., 1999), and 
also including the Gulf of Mexico (Bohlke and Chaplin, 1993). 
Yellowtail damselfish occupy non-overlapping, often contiguous 
territories on solid substrata averaging 44 m\2\ in size (range 14-109 
m\2\, n = 22; P. Sikkel, unpublished data) in which they feed on 
epilithic microalgae (algae growing on rock) and associated microfauna 
(Bohlke and Chaplin, 1968; Sikkel and Kramer, 2006). Adults are 
primarily algae-eaters (Robins et al., 1986), feeding on microalgae, 
epiphytic (growing on a plant) diatoms, and to a lesser extent live 
coral, and are therefore known as facultative corallivores (Cole et 
al., 2008). Adults of both sexes are solitary and they aggressively 
defend their territories against conspecifics and other species to a 
lesser extent (Sikkel and Kramer, 2006). The territories of females 
tend to be shallower and closer to shore than those of males (Sikkel 
and Kramer, 2006).
    Yellowtail damselfish spawning peaks for four to five weeks in 
February to March and again in July to August (Deloach, 1999). Spawning 
occurs during the first 1-3 hours of daylight (Sikkel and Kramer, 2006) 
at regular 3-day intervals from 3 days before to 3 weeks after the full 
moon (Pressley, 1980; Robertson et al., 1990). Females can travel up to 
120 m from their territory to find mates (Sikkel and Kramer, 2006). 
Females lay their entire clutch within the male territory during a 
spawning event and will often mate with the same male over successive 
spawning trips (Sikkel and Kramer, 2006). Male damselfish prepare nests 
within their territories, frequently in coral rubble, and protect the 
eggs (Pressley, 1980). Embryos hatch approximately five days after 
fertilization (Pressley, 1980), and larvae enter a 21 to 27 day pelagic 
phase. They then tend to settle on shallow patch reefs, often inhabited 
by Millepora (fire coral), which Deloach (1999) states makes up much of 
the early diet, and Acropora species rubble habitats (Wilkes et al., 
2008).

Analysis of the Petition

    We evaluated whether the petition presented the information 
required in 50 CFR 424.14(b)(2) and found that the petition contains 
the species' taxonomic description, current geographic distribution, 
habitat characteristics, and threats that could be affecting it. The 
petition does not present any information on past or present population 
numbers, instead it acknowledges that abundance and population trends 
are unknown for the petitioned species, but suggests that the decrease 
in average live coral cover across the Caribbean from 50 to 60 percent 
coverage in the 1970s to 8 percent coverage today suggests reasons for 
concern. The petition does not provide information regarding the status 
of yellowtail damselfish over all or a significant portion of its 
range, other than a discussion of threats. The petition includes 
supporting references.
    The petition states that yellowtail damselfish are vulnerable to 
coral habitat loss and degradation due to temperature-induced coral 
bleaching and ocean acidification, and that this vulnerability is 
heightened given their reliance on live branching corals such as 
species of Millepora and Acropora. The petition states yellowtail 
damselfish are threatened by ocean warming and ocean acidification that 
directly impairs its sensory capabilities, behavior, aerobic capacity, 
swimming ability, and reproduction. The petition also states that the 
global marine aquarium trade and lack of regulatory mechanisms further 
threaten yellowtail damselfish by decreasing their populations in the 
wild.

Information on Population Status, Trends and Demographics Relevant to 
Extinction Risk

    As stated above, the petition does not include any information on 
past or present population numbers, and it acknowledges that abundance 
and population trends are unknown. The petition does not provide 
information regarding the status of yellowtail damselfish over all or a 
significant portion of its range, although one of the references cited 
describes the species as ``common on shallow reefs in the tropical 
Western Atlantic,'' occurring at densities of up to four individuals 
per 100 m\2\ in the Barbados (Sikkel and Kramer, 2006). The petition 
does not identify any risk classifications by other organizations for 
this species.
    There is some information in our files on population status and 
trends for this species in the Florida Keys. We have data on the 
abundance of yellowtail

[[Page 8622]]

damselfish from our Southeast Fisheries Science Center's (SEFSC) Reef 
fish Visual Census (RVC). The RVC is a long-term, spatially-extensive 
survey that has assessed trends in abundance of reef fishes in the 
Florida Keys, by collection of standardized data on trends in frequency 
of occurrence and density. The RVC survey includes data from 1980 
through 2012 for the forereef, high relief spur and groove habitats, 
the preferred habitat zone for yellowtail damselfish (NMFS SEFSC, 
2014). These data show yellowtail damselfish abundance declined during 
the 1980's but stabilized in the 1990's with no apparent trends through 
2012. The RVC data recorded yellowtail damselfish in 93 percent of 
samples (annual average) in the 1980's. Since 1991, the frequency of 
occurrence has averaged around 79 percent, with no apparent trend. 
Similarly, the density of fish, when present, averaged 5 fish per 
standardized sample in the 1980's, and since 1991, the average annual 
density when present has been 2.7 fish per standardized sample, with no 
apparent trend (NMFS SEFSC, 2014). The observed decline in yellowtail 
damselfish frequency and density between the 1980's and the subsequent 
period of 1991-2012 in these data are correlated with the documented 
widespread loss of coral habitat that occurred during the 1980's, as 
noted in the petition. These data also indicate that since the initial 
decline, the long term trend in yellowtail damselfish frequency and 
density over 22 years of data collection has remained stable. We 
interpret these data as indicating a population that has demonstrated 
long term stability, despite significant habitat changes and a one-time 
population decline. Thus, we do not believe the available information 
on population status and trends suggest an extinction risk of concern 
for the species.

Information on Impacts and Threats to the Species

    We also evaluated whether the information in the petition and 
information in our files concerning the extent and severity of one or 
more of the ESA section 4(a)(1) factors suggest these impacts and 
threats may be operative threats that act or have acted on the species, 
posing a risk of extinction for yellowtail damselfish that is cause for 
concern. As stated above in the petition analysis section, the petition 
states that four of the five causal factors in section 4(a)(1) of the 
ESA are adversely affecting the continued existence of yellowtail 
damselfish: (A) Present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for commercial 
and recreational purposes; (D) inadequacy of existing regulatory 
mechanisms; and (E) other natural or manmade factors affecting its 
continued existence. In the following sections, we assess the 
information presented in the petition and readily available in our 
files to determine whether the petitioned action may be warranted.

Present and Threatened Destruction, Modification, or Curtailment of 
Habitat or Range

    The petition states that yellowtail damselfish are ``dependent on 
live coral for shelter, reproduction, recruitment, and/or food, which 
makes them highly vulnerable to coral habitat loss and degradation due 
to ocean warming and ocean acidification and they are habitat 
specialists that rely on branching corals which are particularly 
susceptible to bleaching.'' First we will evaluate the petition's 
arguments that dependency of the yellowtail damselfish on certain 
species of live corals is a source of extinction risk, and then we will 
evaluate the arguments that climate change impacts to the species' 
habitat pose extinction risk that is cause for concern.

Dependency on Branching Coral Species

    The petition cites several studies in support of the argument that 
the yellowtail damselfish specializes on, or relies upon, branching 
corals such as Millepora and Acropora species. The petition cites Allen 
(1991) for the proposition that juvenile yellowtail damselfish ``are 
usually seen among branches of the yellow stinging coral Millepora.'' 
Deloach (1999) is cited for an association between juveniles and blade 
fire coral, M. complanata. Deloach (1999) is also cited as finding that 
Millepora makes up much of the early diet of yellowtail damselfish. The 
Web site www.species-identification.org is similarly cited for the 
statement that yellowtail damselfish are known to feed on the polyps of 
Millepora corals, though as the petition notes from another citation, 
this species is considered a facultative and not an obligate 
corallivore (Cole et al., 2008). Regardless of the importance as food 
or habitat to yellowtail damselfish, the petition does not present 
information that suggests Millepora corals have been affected by the 
numerous threats other corals face, thus we assume their role in the 
yellowtail damselfish's life cycle is unchanged. Additionally, Brainard 
et al. (2011), state ``Millepora are among the first to bleach and die, 
but they seem to have a special aptitude for recovering by recruiting 
new colonies.'' Further, Veron (2000) describes Millepora species as 
``common on reefs.'' Therefore, we do not find population trends of 
Millepora pose an extinction risk that is cause for concern for 
yellowtail damselfish.
    We also reviewed the information in the petition regarding the 
association between adult yellowtail damselfish and elkhorn coral. The 
petition cites Deloach (1999) in describing habitat use by yellowtail 
damselfish. In Deloach (1999), we found the statement ``[l]arge females 
reign over widespread territories of varying sizes on reef crests, 
while males typically occupy deeper zones of Elkhorn rubble.'' This was 
the only information presented in the citation relative to elkhorn 
coral, but it does not indicate yellowtail damselfish specialize on, or 
rely upon, branching coral.
    The petition also cites Tolimieri (1998) as a source for the 
premise that yellowtail damselfish are ``significantly associated with 
Acropora corals and total live coral cover.'' Tolimieri (1998), 
investigated microhabitat substrate use by several damselfish species 
on the Tague Bay Reef, St. Croix, United States Virgin Islands. This 
study evaluated use of Porites spp., Porites spp. rubble, Montastrea 
spp., Montastrea spp. rubble, Acropora spp. rubble, total live coral, 
boulder (unidentified coral) rubble, algae, and pavement/sand 
substrates. The author found that yellowtail damselfish were associated 
more than would be expected by random chance with dead Acropora palmata 
rubble, but not with live coral cover or the only live branching coral 
in the study area--Porites porites. The association between yellowtail 
damselfish and Acropora spp. coral rubble was statistically significant 
(p = 0.043), but only explained 32 percent of the variation in 
abundance of yellowtail damselfish between the various study sites on 
this reef.
    The petition presents Wilkes et al. (2008) for an association of 
adult yellowtail damselfish with live branching staghorn coral in the 
Dry Tortugas, Florida. Wilkes et al. (2008) described their study 
objective as determining what effect, if any, on damselfish could be 
discerned from much of the live staghorn coral in Dry Tortugas National 
Park having been reduced to rubble by extreme cold snaps and disease. 
Wilkes et al. (2008) compared damselfish densities on the largest 
remaining live staghorn coral formation and nearby staghorn coral 
rubble habitat, but did not directly investigate damselfish use of any 
other habitat types in the park. This study found that the density of 
adult

[[Page 8623]]

yellowtail damselfish was greater at sites with live staghorn coral 
compared to nearby sites comprised of dead and broken staghorn coral 
rubble. There was no significant difference in density of juvenile 
yellowtail damselfish between the two sites. These authors suggest that 
``complex reef topography of branching corals like Acropora are thought 
to be a major factor affecting reef fish distribution and abundance'' 
and that the higher adult densities observed in this study ``may be 
related to the increase in three-dimensional habitat that would provide 
predator refuge dimensions more conducive to adult body sizes that 
require larger shelter spaces.'' The authors conclude that ``reductions 
in damselfish density are the likely outcome in reefs where expanses of 
live branching coral are in decline and are being replaced by 
relatively low-dimensional fields of reef rubble.'' Finally, Wilkes et 
al. (2008) note that ``some damselfish species may require the habitat 
complexity provided by branching corals, whereas others are better 
suited to exploit a wide range of habitat types and display no specific 
coral preference.'' However, the authors make no conclusion about 
yellowtail damselfish and their habitat usage, though they do note 
another study (Wallman et al., 2006) that found that patch reefs 
lacking in live branching corals within Dry Tortugas National Park 
support populations of adult yellowtail damselfish.
    In our files we also have available Waldner and Robertson (1980) 
that considers patterns of spatial distribution and resource 
partitioning in damselfish to explain how ecologically similar reef 
fishes can co-exist on various spatial scales. Field surveys recorded 
yellowtail damselfish in Puerto Rico between 1976 and 1978 at both 
inshore and offshore reefs and recorded substrate within 15 cm (5.9 
inches) of where the species was observed or the substrate where the 
fish sought refuge when rapidly approached by a diver. A total of 54 
adult yellowtail damselfish were reported on 4 out of 6 substrate 
types: 48 percent of observations were associated with non-branching 
massive corals such as Montastraea annularis, 24 percent of the 
observations were associated each with elkhorn (A. palmata) and 
staghorn (A. cervicornis) coral, and 4 percent were associated with 
Millepora spp. When the amount of the different substrate types within 
the transect area was considered, elkhorn coral was found to be a most-
used substrate. Waldner and Robertson (1980) then compared their 
results with the results of other studies that occurred throughout the 
West Indies in the 1970's and concluded their results were in agreement 
in most cases that adult yellowtail damselfish were most 
characteristically associated with elkhorn coral and Millepora in very 
shallow to moderate depth range.
    Prior to the 1980's, Acropora corals were the overwhelmingly 
dominant reef-building coral on Caribbean reefs, to the extent that 
depth zones were named after these species (``elkhorn zone,'' 
``staghorn zone'') (Goreau, 1959). Given the dominance of these corals, 
it is reasonable to expect that yellowtail damselfish and many other 
reef fishes were found associated with acroporids then as well. For 
example, Waldner and Robertson (1980) found a significant association 
between yellowtail damselfish and elkhorn corals in the 1970's. During 
the 1980's, a massive die-off of Acropora species occurred in the 
Caribbean. The decline in Acropora species was greater than 90 percent 
(Ginsburg, 1994; Hughes, 1994; McClanahan and Muthiga, 1998). As the 
SEFSC RVC data indicate, yellowtail damselfish abundance declined in 
fore-reef, spur and groove habitats in the Florida Keys in the 1980's. 
The initial decline in yellowtail damselfish abundance is likely linked 
to the widespread die-off of corals. However, the yellowtail damselfish 
population has remained stable since 1991. Although the Florida Keys 
population is at a lower level than it was in the 1970's and 1980's, 
the stability in abundance indicates that it is not so low that 
depensatory processes, such as declining mate-finding ability or 
escalating risk of predation, are an extinction risk factor. Therefore, 
we conclude that the yellowtail damselfish is not dependent on 
acroporid corals to the extent that the decline of Acropora habitat 
presents an extinction risk that is cause for concern.
    In summary, we acknowledge that yellowtail damselfish was 
historically associated with Acropora corals in the Caribbean (Waldner 
and Robertson, 1980), and exhibited a population decline in habitats 
dominated by Acropora concurrent with the massive die-off of corals in 
the 1980s. However, the available information demonstrates yellowtail 
damselfish associate with a variety of coral species and habitats 
(Tolimieri, 1998; Wilkes et al, 2008) within the coral-reef ecosystem 
(e.g., branching, boulder, and dead rubble), and appear in at least one 
instance (Florida Keys) to have inhabited reef areas at stable 
population levels for over 20 years after the widespread decline of 
acroporids. Therefore, the loss of the branching elkhorn and staghorn 
corals does not constitute an extinction risk for the yellowtail 
damselfish that is a cause for concern.

Climate Change Impacts to Coral Reef Ecosystems Generally as a Threat 
to Yellowtail Damselfish

    The petition discusses at length climate change impacts to corals 
and coral reefs and future predictions for worsening impacts to corals 
at a global scale, and argues that these impacts pose extinction risk 
to yellowtail damselfish through destruction, modification or 
curtailment of its habitat. As discussed above, while the petition 
establishes an association with live branching coral species for 
yellowtail damselfish, we have established that they also associate 
with other coral species and forms within the coral-reef ecosystem and 
are not reliant upon branching corals for habitat.
    Many of the references provided in the petition offer global 
predictions on future rises in sea surface temperature (Donner et al., 
2005; Donner, 2009), ocean acidity (Hoegh-Guldberg et al., 2007), or 
coral reef decline in general (Hoegh-Guldberg, 1999; Veron et al., 
2009). Emission rates of greenhouse gases (GHG) associated with ocean 
warming have in recent years met or exceeded levels found in the worst-
case scenarios considered by the Intergovernmental Panel on Climate 
Change (IPCC), resulting in all scenarios underestimating the projected 
future climate condition. New information suggests that regardless of 
the emission concentration pathway, more than 97 percent of reefs will 
experience severe thermal stress by 2050 (Meissner et al., 2012). At 
the same time new information also highlights the spatial and temporal 
``patchiness'' of warming (79 FR 53851; September 10, 2014). This 
patchiness moderates vulnerability of corals to extinction because most 
species are not limited to one habitat type but occur in numerous types 
of reef environments that are predicted, on local and regional scales, 
to experience variable thermal regimes and ocean chemistry at any given 
point in time (79 FR 53851; September 10, 2014). Overall, there is 
ample evidence that climate change (including that which is already 
committed to occur from past GHG emissions and future emissions 
reasonably certain to occur) and will lead to a worsening environment 
for corals.
    If many coral species are to survive anticipated global warming, 
corals and their zooxanthellae will have to undergo significant 
acclimatization and/or adaptation. There has been a recent research 
emphasis on the processes of acclimatization and adaptation in

[[Page 8624]]

corals. For example, the results of a study funded by NOAA and 
conducted by the agency's scientists and its academic partners suggests 
some coral species may be able to adapt to moderate climate warming, 
improving their chance of surviving through the end of this century, if 
there are large reductions in carbon dioxide emissions (Logan et al, 
2013). Results of this study further suggest some corals have already 
adapted to part of the warming that has occurred in the past. The study 
modeled a range of possible coral adaptive responses to thermal stress, 
and projected that, through processes such as genetic adaptation, 
acclimation, and symbiont shuffling, the reefs could reduce the rate of 
temperature-induced bleaching by 20 to 80 percent of levels currently 
projected to occur by the year 2100, if there are large reductions in 
carbon dioxide emissions. The authors emphasize the caveat that coral 
adaptation will not significantly slow the loss of coral reefs if there 
is no decrease in GHG emissions and further, that not all species will 
be able to adapt fast enough or to the same extent.
    Thus, as a whole, the body of research on coral adaptation to 
global warming is inconclusive on how these processes may affect 
particular coral species' extinction risk, given the projected 
intensity and rate of ocean warming (Brainard et al., 2011).
    Similarly, because of the increase in carbon dioxide and other GHGs 
in the atmosphere since the industrial revolution, ocean acidification 
has already occurred throughout the world's oceans, including in the 
Caribbean, and is predicted to considerably worsen between now and 
2100. Overall, available information demonstrates that most corals 
exhibit declining calcification rates with rising carbon dioxide 
concentrations, declining pH, and declining carbonate saturation 
state--although the rate and mode of decline can vary among species (79 
FR 53851; September 10, 2014). Spatially, while carbon dioxide levels 
in the surface waters of the ocean are generally in equilibrium with 
the lower atmosphere, there can be considerable spatial variability in 
seawater pH across reef-building coral habitats, resulting in colonies 
of a species experiencing high spatial variability in exposure to ocean 
acidification (79 FR 53851; September 10, 2014).
    As we have discussed elsewhere (79 FR 53851; September 10, 2014), 
vulnerability of a coral species to a threat is a function of 
susceptibility and exposure, considered at the appropriate spatial and 
temporal scales. Susceptibility of a coral species to a threat is 
primarily a function of biological processes and characteristics, and 
can vary greatly between and within taxa (i.e., family, genus, or 
species). Susceptibility depends on direct effects of the threat on the 
species, and it also depends on the cumulative (i.e., additive) and 
interactive (i.e., synergistic or antagonistic) effects of multiple 
threats acting simultaneously on the species. For example, ocean 
warming affects coral colonies through the direct effect of bleaching, 
together with the interactive effect of bleaching and disease, because 
bleaching increases disease susceptibility. Vulnerability of a coral 
species to a threat also depends on the proportion of colonies and 
populations that are exposed to the threat. Exposure is primarily a 
function of the distribution of the threat. The degree or intensity of 
exposure to a threat is primarily a function of physical processes and 
characteristics that limit or moderate the intensity of the threat 
across the range of the species. In our final listing rule responding 
to a petition to list 83 species of corals, we found that not all coral 
species are highly vulnerable to the threats associated with global 
climate change (79 FR 53851; September 10, 2014). Even some species 
found to be susceptible to ocean warming were found not warranted for 
listing because they may have a buffering capacity to resist adverse 
effects on their status, due to high abundance, wide range, and/or high 
habitat heterogeneity.
    With information indicating yellowtail damselfish associate with a 
variety of coral habitats, and because susceptibility of coral species 
to climate change impacts is highly variable, we cannot infer any level 
of extinction risk from habitat loss due to climate change for 
yellowtail damselfish. Further, in a review of six studies examining 
the effects of coral bleaching on coral-reef fishes, Pratchett et al. 
(2008) found the density of 45 of 116 fish species' showed significant 
changes 1-3 years post-bleaching. The responses ranged from local 
extinction to several-fold increases in abundance. Though the 
damselfishes included in their study showed mixed results, Pratchett et 
al. (2008) found ``fishes that increased in abundance were mostly 
dietary and habitat generalist species,'' but some herbivores also 
showed increases. Thus, we do not view this study as providing any 
reliable prediction of yellowtail damselfish responses to coral 
bleaching. The petition also cites Bonin (2012) for effects of coral 
bleaching on damselfish. The paper concludes that as a result of coral 
mortality from bleaching, ``[fish] specialists will increasingly be 
forced to use alternative recruitment habitats, and that is likely to 
reduce population replenishment.'' As noted above, however, yellowtail 
damselfish is not a specialist on any particular coral species. Bonin 
(2012) further states that the ``available evidence suggests that the 
presence of conspecifics provides a stronger cue for settlement than 
does microhabitat (Booth, 1992; Lecchini et al., 2005a; 2005b).'' Thus, 
the presence of established individuals of the same fish species was 
more important for settling recruits than was habitat in that study. A 
third study cited by the petition, Booth and Beretta (2012), provided 
examples of fish recruit abundance decline independent of coral 
bleaching and concluded ``these examples highlight the stochastic 
nature of recruitment, and caution against the hasty attribution of 
cause and effect in explaining changes in recruitment through time.'' 
Graham et al. (2007) was also cited by the petition as an example of 
the effects of bleaching on coral-reef fishes. The authors concluded 
that ``of the indirect effects of bleaching that we have identified, 
one of the most significant for the reef ecosystem as a whole is likely 
to be the decline in smaller size classes of herbivorous fishes (mainly 
surgeonfishes and parrotfishes with some rabbitfishes and two species 
of damselfish).'' The petition also cites Wilson et al. (2006) for 
effects of bleaching on coral-reef fishes; however, Wilson et al. 
(2006) found ``abundances of species reliant on live coral for food and 
shelter consistently declined during this time frame, while abundance 
of some species that feed on invertebrates, algae and/or detritus 
increased. The response of species, particularly those expected to 
benefit from the immediate loss of coral, is variable.'' Thus, given 
that yellowtail damselfish is not an obligate corallivore and has a 
varied diet including algae and invertebrates, this study is not 
indicative of potential adverse impacts to yellowtail damselfish from 
coral bleaching. Finally, the petition cites Bonin et al. (2009) for 
effects of bleaching on coral-reef fishes. This study examined the 
effects of bleaching on two species of gobies that are live-coral 
symbionts. Again, this information does not allow us to infer any level 
of extinction risk from coral reef habitat loss due to climate change 
impacts for yellowtail damselfish.
    Therefore, we find that the petition does not provide substantial 
scientific or commercial information indicating that listing yellowtail 
damselfish as

[[Page 8625]]

threatened or endangered may be warranted due to loss or degradation of 
coral habitat that may result from global climate change.

Overutilization for Commercial and Recreational Purposes

    The petition provides information indicating damselfish are the 
most commonly harvested group of fishes in the global trade of marine 
aquarium fish. The petition does not include any information specific 
to the collection of yellowtail damselfish, nor does it provide any 
explanation of how harvest of yellowtail damselfish is an extinction 
risk to the species. Due to the pugnacious behavior of yellowtail 
damselfish and its solitary nature (Robins et al., 1986), it is likely 
a less desirable species for use in aquaria compared to damselfish that 
are schooling planktivores such as the blue-green chromis. Though we do 
not have information in our files for harvest and trade impacts across 
the entire range of the species, we do have information in our files 
about harvest of damselfish in Florida for the aquarium trade; 9,780 
damselfish were collected in 2009 from Florida waters for the aquarium 
trade. There are 14 species of damselfish in Florida waters and 
yellowtail damselfish is considered ``common'' (Humann, 1999), but 
specific information regarding the contribution of yellowtail 
damselfish to the aquarium trade harvest in Florida is not available 
(FWRI, 2009). Even if we assumed the entire Florida harvest in 2009 was 
comprised of yellowtail damselfish and is representative of ongoing 
harvest levels, we do not believe the collection of nearly 10,000 
individuals in Florida annually would constitute an extinction risk 
that is cause for concern to the status of yellowtail damselfish. 
Because field surveys throughout the Florida Keys forereef, high relief 
spur and groove habitat indicate yellowtail damselfish have remained 
stable in frequency and density for the last 22 years (NMFS SEFSC, 
2014), we believe harvest is not contributing to a decline in total 
numbers within Florida. In summary, we find the petition and 
information in our files do not present substantial scientific or 
commercial information to suggest that listing yellowtail damselfish as 
threatened or endangered may be warranted due to overutilization for 
commercial, recreational, educational, or scientific purposes.

Inadequacy of Existing Regulatory Mechanisms

    The petition states the regulatory mechanisms addressing greenhouse 
gas pollution, protecting coral reef habitat, and controlling the 
aquarium trade are inadequate to protect the yellowtail damselfish and 
that the ``widespread and growing trade in coral-reef fish and corals 
adds to the cumulative stresses . . . from ocean warming and ocean 
acidification.'' The petition states that both international and 
domestic laws controlling greenhouse gas emissions are inadequate and/
or have failed to control emissions, ``as acknowledged by NMFS in its 
Status Review Report of 82 Candidate Coral Species and Accompanying 
Management Report.'' We concur there is information in the petition, 
readily available in our files, and from scientific literature that 
indicates GHG emissions and associated ocean warming, acidification and 
other synergistic effects are contributing to extinction risk for some 
species of reef building corals (79 FR 53851; September 10, 2014), and 
that existing regulatory mechanisms are inadequate to prevent these 
emissions from causing serious harmful impacts to corals. However, we 
do not have information in our files, and we are not aware of any 
literature, indicating GHG emissions are negatively affecting 
yellowtail damselfish (e.g., through sensory impacts, discussed below). 
As discussed above, yellowtail damselfish associate with a variety of 
coral-reef habitats and we have no information from which to conclude 
the impacts of GHG emissions on coral reefs present extinction risk 
that is cause for concern for yellowtail damselfish. Therefore, we also 
cannot conclude that inadequacy of regulatory mechanisms to control 
these emissions is causing extinction risk that is cause for concern 
for this species.
    The petition states that existing regulatory mechanisms are 
inadequate to protect coral reef habitats from local threats (e.g., 
overfishing), despite international and domestic efforts to reduce 
threats to reefs. The petition cites Burke et al. (2011), as concluding 
that ``[m]ore than 60% of the world's coral reefs are under immediate 
and direct threat from one or more local sources,'' and that ``[of] 
local pressures on coral reefs, overfishing--including destructive 
fishing--is the most pervasive immediate threat, affecting more than 55 
percent of the world's reefs.'' The petition states ``this high level 
of threat clearly indicates that existing regulatory mechanisms are 
inadequate to protect the coral reefs on which the petitioned 
Pomacentrids depend.'' However, the petition fails to discuss how 
yellowtail damselfish may be susceptible to this generalized threat to 
coral reefs.
    The petition states that regulation of the aquarium trade is 
inadequate to control trade and prevent collection detrimental to the 
species' survival. The petition cites Tissot et al. (2010) for evidence 
of ``weak governance capacity in major source countries such as 
Indonesia and the Philippines; high international demand, particularly 
from the United States . . . and inadequate enforcement of the few 
existing laws, allowing collectors to use illegal and harmful 
collection methods such as sodium cyanide.'' Drawing inferences based 
on Indo-Pacific species and the regulatory mechanisms governing their 
collection is inappropriate because yellowtail damselfish do not occur 
in the foreign countries in the Indo-Pacific discussed as having 
inadequate governance and enforcement of laws. There is no information 
in our files indicating yellowtail damselfish is a highly prized, 
collected, or traded marine organism. We conclude the threats 
characterization in the petition regarding inadequacy of regulatory 
mechanisms to control harmful harvest of yellowtail damselfish is 
unsubstantiated.
    In summary we find the petition does not provide substantial 
scientific or commercial information to suggest that existing 
regulatory mechanisms related to any identified threats to the species 
are inadequate such that they may be causing an extinction risk for the 
yellowtail damselfish.

Other Natural or Manmade Factors

    The petition states that ocean acidification and ocean warming, in 
addition to causing habitat loss, ``directly threaten the survival of 
the petitioned species through a wide array of adverse impacts that are 
predicted to lead to negative fitness consequences and population 
declines.'' The petition states ``ocean acidification impairs the 
sensory capacity and behavior of larval clownfish and damselfish.'' The 
petition refers to a number of sources to demonstrate that in the 
laboratory, behavioral responses of larval fish can be affected by 
elevated carbon dioxide levels.
    The petition states ``research on the effects of ocean 
acidification on six species of larval damselfish found that elevated 
carbon dioxide levels expected within this century impair damselfish 
smell, vision, learning, behavior, and brain function, leading to a 
higher risk of mortality.'' Results from two of these six damselfish 
are from Munday et al. (2010) who found that ``700 ppm carbon dioxide 
is close to the threshold at which adaptation of behavioral responses 
might be possible in reef

[[Page 8626]]

fishes, provided that the variation in sensitivity to elevated carbon 
dioxide we observed between individuals at this concentration has a 
genetic basis. The olfactory capacity of approximately one-half of the 
larvae was unaffected by exposure to 700 ppm carbon dioxide, and these 
individuals exhibited less risky behavior in the field (remained closer 
to shelter) compared with affected individuals.'' The effect on 
olfactory capacity appears to be an individual response and not 
necessarily a population response. A variable individual response does 
not constitute a risk to the entire population and therefore, there is 
not sufficient evidence of extinction risk to yellowtail damselfish 
posed by elevated carbon dioxide impacts on olfactory capacity.
    Results from the other four of these six damselfish species are 
from Ferrari et al. (2011), where the effects of carbon dioxide 
exposure on the antipredator responses of four sympatric species who 
share the same ecology and life history was tested; all four are 
congeners in a different genus than yellowtail damselfish and all are 
found in the Pacific Ocean. The four damselfish in the Ferrari et al. 
(2011) study were specifically selected to compare similar species 
response to carbon dioxide in order to predict ecological impacts on 
marine communities. The concentrations of carbon dioxide tested ranged 
from those similar to recent atmospheric concentrations (390 ppm) to 
those representing highly elevated (700 and 850 ppm) atmospheric 
levels. This was accomplished by placing juveniles collected in traps 
into 35 L rearing aquariums that were either aerated with 390 ppm 
(current-day control), 728  88, or 1008  78 ppm 
(mean  SD) carbon dioxide enriched air (Munday et al., 
2009; Dixson et al., 2010) creating environments with 700 and 850 ppm 
CO2 (see Munday et al. (2010) for more details). While 
Ferrari et al. (2011) predicted the difference in behavioral response 
in the lab would translate into differential survival in the field, the 
``four congeneric species showed striking and unexpected variation in 
CO2 tolerance.'' The antipredator responses were reduced at 
the 700 ppm level, but did not disappear, while at the 850 ppm level, 
three out of four species did not show an adaptive antipredator 
response, and the fourth maintained an antipredator response similar to 
the response level of the 700 ppm exposure. Additionally, all fish 
displayed antipredator responses to odors from injured conspecifics, 
which is considered a reliable cue of general predation risk (Ferrari 
et al., 2010). The results by Ferrari et al. (2011) were described by 
the petitioner as highlighting how individual effects from elevated 
carbon dioxide are highly uncertain and constitute an extinction risk 
for the petitioned species. However, merely identifying factors that 
could negatively impact a species does not constitute substantial 
information that listing may be warranted. Because Ferrari et al. 
(2011) found ``marked intraspecific variation,'' we interpret these 
results to demonstrate variability in physiological responses within 
the functional group examined (functional groups were defined by their 
carbon dioxide tolerance). Further, Ferrari et al. (2011) found 
predation rates and prey selectivity were impacted by exposure to 
elevated levels of dissolved carbon dioxide, but the outcome of the 
interaction was dependent on the size of juvenile prey, not on the 
species. Additionally, Ferrari et al. (2011) concluded that if the 
negative effects of carbon dioxide were balanced between prey and 
predators, we would not expect any change in overall mortality rate. 
These data do not provide reliable information for conclusions about 
the response of the yellowtail damselfish, much less a population-level 
response that might occur if the carbon dioxide levels tested are 
eventually reached. Finally, Ferrari et al. (2011) note that their 
experimental results may represent a worst case scenario in that it 
assumes absence of adaptation. We do not have information in our files, 
and we are not aware of any literature, indicating increased carbon 
dioxide levels have reduced fitness of any western Atlantic damselfish, 
or that increased levels may pose an extinction risk that is cause for 
concern for yellowtail damselfish.
    The petition also states that elevated sea surface temperatures 
``can influence the physiological condition, developmental rate, growth 
rate, early life history traits, and reproductive performance of coral 
reef fishes, all of which can affect their population dynamics, 
community structure, and geographical distributions,'' citing Nilsson 
et al. (2009). We reviewed Nilsson et al. (2009) and found the results 
show physiological responses to changes in water temperature. Nilsson 
et al. (2009) examined the capacity of five species of marine fish to 
perform aerobically (aerobic scope). They found that all five species 
exhibited a decline in aerobic capacity at elevated water temperatures 
(31, 32, or 33 [deg]C) compared to the control (29 [deg]C); the three 
damselfish species tested retained over half their aerobic scope at 33 
[deg]C, while all capacity for additional oxygen uptake was exhausted 
at 33 [deg]C for the two cardinalfish species tested. One damselfish 
species' oxygen uptake was reduced from 142% at 29 [deg]C to 81% at 31 
[deg]C while another species' uptake went from 300% at 29 [deg]C to 
178% at 33 [deg]C. These results indicate that damselfish are thermally 
tolerant and as Nilsson et al. (2009) state, ``populations of thermally 
tolerant species are likely to persist at higher temperatures, but 
populations of thermally sensitive species could decline on low-
latitude reefs if individual performance falls below levels needed to 
sustain viable populations.
    The petition cites several other sources, primarily Johansen and 
Jones (2011), which found increasing temperatures have negative effects 
on the aerobic capacity and swimming performance of some damselfish, 
though the species tested did not include the yellowtail damselfish or 
any of its congeners. These studies also revealed inter-specific 
differences in the response to elevated temperature and discussed how 
acclimation, developmental plasticity, and adaptation can alleviate 
temperature-related physiological impacts. All but one of these studies 
were single generation studies and did not evaluate trans-generational 
plasticity for any species to determine if the species are able to 
adapt or acclimate to new environmental conditions over time. In fact, 
the one study that did (Donelson et al., 2011) found that ``complete 
compensation in aerobic scope occurred when both parents and offspring 
were reared throughout their lives at elevated temperature. Such 
acclimation could reduce the impact of warming temperatures and allow 
populations to persist across their current range. This study reveals 
the importance of trans-generational (across generations) acclimation 
as a mechanism for coping with rapid climate change and highlights that 
single generation studies risk underestimating the potential of species 
to cope.'' The petition does not provide any information about the 
aerobic scope of yellowtail damselfish, nor do we have any information 
in our files. Therefore, we do not believe Nilsson et al. (2009), 
Donelson et al. (2011), and Johansen and Jones (2011), are reliable 
sources for the premise that elevated sea temperatures will affect the 
physiological response of yellowtail damselfish to the extent it poses 
an extinction risk of concern to the species.
    Results from a study by Munday et al. (2008) are also included in 
the petition to indicate how larval growth rates and recruitment of 
some reef fishes can increase with warmer water. Munday et

[[Page 8627]]

al. (2008) documented high variability in response at both the 
individual and species level. Many coral reef fishes have geographical 
ranges spanning a wide temperature gradient and some have short 
generation times. These characteristics are conducive to acclimation or 
local adaptation to climate change and provide potential for more 
resilient species to persist (Munday et al., 2008).
    Thus, we conclude the petition did not explain, nor do we have 
information in our files explaining, how physiological effects of 
elevated carbon dioxide or elevated temperature would have negative 
effects on yellowtail damselfish. As we have noted, many of the 
references presented by the petition show highly variable physiological 
responses by individuals and species to various stimuli (elevated 
carbon dioxide or increased temperatures) and no reliable inference to 
yellowtail damselfish population responses can be drawn. We conclude 
the petition does not provide reliable support for the premise that the 
effects of ocean warming or ocean acidification may be posing 
extinction risk that is cause for concern for yellowtail damselfish.
    In summary, we conclude the petitions' characterization of ocean 
acidification and ocean warming as posing negative fitness consequences 
to be broad statements of generalized threats and do not indicate that 
ocean acidification and ocean warming directly threaten the survival or 
pose extinction risk that is cause for concern to the yellowtail 
damselfish. Therefore, we conclude the petition does not present 
substantial scientific or commercial information indicating the 
petitioned action may be warranted due to other natural or manmade 
factors.

Synergistic threats

    Additionally, we do not find that the combination of proposed 
threats to yellowtail damselfish poses extinction risk that is cause 
for concern for yellowtail damselfish. The proposed threat from loss of 
habitat or habitat degradation is overstated because not all coral 
species are highly vulnerable to the threats associated with global 
climate change, some coral species will survive, and yellowtail 
damselfish are capable of habitat adaptations in response to changes in 
composition of coral species on reefs; harvest of the species is 
minimal; and physiological responses to increased carbon dioxide levels 
and sea temperature vary widely. Therefore, we do not believe these 
proposed threats act synergistically on yellowtail damselfish to pose 
extinction risk that is cause for concern.

Finding

    After reviewing the information contained in the petition, as well 
as information readily available in our files, we conclude the petition 
does not present substantial scientific or commercial information 
indicating that listing the yellowtail damselfish as either an 
endangered species or as a threatened species may be warranted.

References Cited

    A complete list of all references is available on our Web site: 
http://sero.nmfs.noaa.gov/protected_resources/listing_petitions/species_esa_consideration/index.html .

Authority

    The authority for this action is the Endangered Species Act of 
1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: February 11, 2015.
Samuel D. Rauch, III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.
[FR Doc. 2015-03326 Filed 2-17-15; 8:45 am]
BILLING CODE 3510-22-P


Current View
CategoryRegulatory Information
CollectionFederal Register
sudoc ClassAE 2.7:
GS 4.107:
AE 2.106:
PublisherOffice of the Federal Register, National Archives and Records Administration
SectionNotices
ActionNotice of 90-day petition finding.
ContactJason Rueter, NMFS Southeast Region, 727-824-5312.
FR Citation80 FR 8619 
RIN Number0648-XC56

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