12-Month Finding on a Petition To List Giant and Reef Manta Rays as Threatened or Endangered Under the Endangered Species Act, 3694-3715 [2017-00370]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 82, Number 8 (Thursday, January 12, 2017)]
[Proposed Rules]
[Pages 3694-3715]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-00370]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 223

[Docket No. 160105011-6999-02]
RIN 0648-XE390


12-Month Finding on a Petition To List Giant and Reef Manta Rays 
as Threatened or Endangered Under the Endangered Species Act

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

ACTION: Proposed rule; 12-month petition finding; request for comments.

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SUMMARY: We, NMFS, announce a 12-month finding on a petition to list 
the giant manta ray (Manta birostris) and reef manta ray (Manta 
alfredi) as threatened or endangered under the Endangered Species Act 
(ESA). We have completed a comprehensive status review of both species 
in response to this petition. Based on the best scientific and 
commercial information available, including the status review report 
(Miller and Klimovich 2016), and after taking into account efforts 
being made to protect these species, we have determined that the giant 
manta ray (M. birostris) is likely to become an endangered species 
within the foreseeable future throughout a significant portion of its 
range. Therefore, we propose to list the giant manta ray as a 
threatened species under the ESA. Any protective regulations determined 
to be necessary and advisable for the conservation of the proposed 
threatened giant manta ray under ESA section 4(d) would be proposed in 
a subsequent Federal Register announcement. Should the proposed listing 
be finalized, we would also designate critical habitat for the species, 
to the maximum extent prudent and determinable. We solicit information 
to assist this proposed listing determination, the development of 
proposed protective regulations, and

[[Page 3695]]

designation of critical habitat in the event the proposed threatened 
listing for the giant manta ray is finalized. Additionally, we have 
determined that the reef manta ray (M. alfredi) is not currently in 
danger of extinction throughout all or a significant portion of its 
range and is not likely to become so within the foreseeable future. 
Therefore, we find that the reef manta ray does not warrant listing 
under the ESA at this time.

DATES: Comments on the proposed rule to list the giant manta ray must 
be received by March 13, 2017. Public hearing requests must be made by 
February 27, 2017.

ADDRESSES: You may submit comments on this document, identified by 
NOAA-NMFS-2016-0014, by either of the following methods:
     Electronic Submissions: Submit all electronic public 
comments via the Federal eRulemaking Portal. Go to www.regulations.gov/#!docketDetail;D=NOAA-NMFS-2016-0014. Click the ``Comment Now'' icon, 
complete the required fields, and enter or attach your comments.
     Mail: Submit written comments to Maggie Miller, NMFS 
Office of Protected Resources (F/PR3), 1315 East West Highway, Silver 
Spring, MD 20910, USA.
    Instructions: Comments sent by any other method, to any other 
address or individual, or received after the end of the comment period, 
may not be considered by NMFS. All comments received are a part of the 
public record and will generally be posted for public viewing on 
www.regulations.gov without change. All personally identifying 
information (e.g., name, address, etc.), confidential business 
information, or otherwise sensitive information submitted voluntarily 
by the sender will be publicly accessible. NMFS will accept anonymous 
comments (enter ``N/A'' in the required fields if you wish to remain 
anonymous).
    You can find the petition, status review report, Federal Register 
notices, and the list of references electronically on our Web site at 
www.fisheries.noaa.gov/pr/species/fish/manta-ray.html.

FOR FURTHER INFORMATION CONTACT: Maggie Miller, NMFS, Office of 
Protected Resources, (301) 427-8403.

SUPPLEMENTARY INFORMATION: 

Background

    On November 10, 2015, we received a petition from Defenders of 
Wildlife to list the giant manta ray (M. birostris), reef manta ray (M. 
alfredi) and Caribbean manta ray (M. c.f. birostris) as threatened or 
endangered under the ESA throughout their respective ranges, or, as an 
alternative, to list any identified distinct population segments (DPSs) 
as threatened or endangered. The petitioners also requested that 
critical habitat be designated concurrently with listing under the ESA. 
On February 23, 2016, we published a positive 90-day finding (81 FR 
8874) announcing that the petition presented substantial scientific or 
commercial information indicating that the petitioned action may be 
warranted for the giant manta ray and reef manta ray, but that the 
Caribbean manta ray is not a taxonomically valid species or subspecies 
for listing, and explained the basis for that finding. We also 
announced the initiation of a status review of the giant manta ray and 
reef manta ray, as required by section 4(b)(3)(a) of the ESA, and 
requested information to inform the agency's decision on whether these 
species warrant listing as endangered or threatened under the ESA.

Listing Species Under the Endangered Species Act

    We are responsible for determining whether giant and reef manta 
rays are threatened or endangered under the ESA (16 U.S.C. 1531 et 
seq.). To make this determination, we first consider whether a group of 
organisms constitutes a ``species'' under section 3 of the ESA, then 
whether the status of the species qualifies it for listing as either 
threatened or endangered. Section 3 of the ESA defines species to 
include ``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.'' On February 7, 1996, NMFS and 
the U.S. Fish and Wildlife Service (USFWS; together, the Services) 
adopted a policy describing what constitutes a DPS of a taxonomic 
species (61 FR 4722). The joint DPS policy identified two elements that 
must be considered when identifying a DPS: (1) The discreteness of the 
population segment in relation to the remainder of the species (or 
subspecies) to which it belongs; and (2) the significance of the 
population segment to the remainder of the species (or subspecies) to 
which it belongs.
    Section 3 of the ESA defines an endangered species as ``any species 
which is in danger of extinction throughout all or a significant 
portion of its range'' and a threatened species as one ``which is 
likely to become an endangered species within the foreseeable future 
throughout all or a significant portion of its range.'' Thus, in the 
context of the ESA, the Services interpret an ``endangered species'' to 
be one that is presently at risk of extinction. A ``threatened 
species'' is not currently at risk of extinction, but is likely to 
become so in the foreseeable future. The key statutory difference 
between a threatened and endangered species is the timing of when a 
species may be in danger of extinction, either now (endangered) or in 
the foreseeable future (threatened).
    Additionally, as the definition of ``endangered species'' and 
``threatened species'' makes clear, the determination of extinction 
risk can be based on either assessment of the range wide status of the 
species, or the status of the species in a ``significant portion of its 
range.'' The Services published a final policy to clarify the 
interpretation of the phrase ``significant portion of the range'' in 
the ESA definitions of ``threatened species'' and ``endangered 
species'' (79 FR 37577; July 1, 2014) (SPR Policy). The policy consists 
of the following four components:
    (1) If a species is found to be endangered or threatened in only an 
SPR, and the SPR is not a DPS, the entire species is listed as 
endangered or threatened, respectively, and the ESA's protections apply 
across the species' entire range.
    (2) A portion of the range of a species is ``significant'' if its 
contribution to the viability of the species is so important that 
without that portion, the species would be in danger of extinction or 
likely to become so in the foreseeable future.
    (3) The range of a species is considered to be the general 
geographical area within which that species can be found at the time 
USFWS or NMFS makes any particular status determination. This range 
includes those areas used throughout all or part of the species' life 
cycle, even if they are not used regularly (e.g., seasonal habitats). 
Lost historical range is relevant to the analysis of the status of the 
species, but it cannot constitute an SPR.
    (4) If a species is not endangered or threatened throughout all of 
its range but is endangered or threatened within an SPR, and the 
population in that significant portion is a valid DPS, we will list the 
DPS rather than the entire taxonomic species or subspecies.
    The statute also requires us to determine whether any species is 
endangered or threatened throughout all or a significant portion of its 
range as a result of any one or a combination of the following five 
factors: the present or threatened destruction, modification, or

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curtailment of its habitat or range; overutilization for commercial, 
recreational, scientific, or educational purposes; disease or 
predation; the inadequacy of existing regulatory mechanisms; or other 
natural or manmade factors affecting its continued existence (ESA 
section 4(a)(1)(A)-(E)). Section 4(b)(1)(A) of the ESA requires us to 
make listing determinations based solely on the best scientific and 
commercial data available after conducting a review of the status of 
the species and after taking into account efforts being made by any 
State or foreign nation or political subdivision thereof to protect the 
species. In evaluating the efficacy of existing domestic protective 
efforts, we rely on the Services' joint Policy on Evaluation of 
Conservation Efforts When Making Listing Decisions (``PECE''; 68 FR 
15100; March 28, 2003) for any conservation efforts that have not been 
implemented, or have been implemented but not yet demonstrated 
effectiveness.

Status Review

    A NMFS biologist in the Office of Protected Resources led the 
status review for the giant manta ray and reef manta ray (Miller and 
Klimovich 2016). The status review examined both species' statuses 
throughout their respective ranges and also evaluated if any portion of 
their range was significant as defined by the Services' SPR Policy (79 
FR 37578; July 1, 2014).
    In order to complete the status review, information was compiled on 
each species' biology, ecology, life history, threats, and status from 
information contained in the petition, our files, a comprehensive 
literature search, and consultation with experts. We also considered 
information submitted by the public in response to our petition 
finding. In assessing the extinction risk of both species, we 
considered the demographic viability factors developed by McElhany et 
al. (2000). The approach of considering demographic risk factors to 
help frame the consideration of extinction risk has been used in many 
of our status reviews, including for Pacific salmonids, Pacific hake, 
walleye pollock, Pacific cod, Puget Sound rockfishes, Pacific herring, 
scalloped, great, and smooth hammerhead sharks, and black abalone (see 
www.nmfs.noaa.gov/pr/species/ for links to these reviews). In this 
approach, the collective condition of individual populations is 
considered at the species level according to four viable population 
descriptors: abundance, growth rate/productivity, spatial structure/
connectivity, and diversity. These viable population descriptors 
reflect concepts that are well-founded in conservation biology and that 
individually and collectively provide strong indicators of extinction 
risk (NMFS 2015).
    The draft status review report was subjected to independent peer 
review as required by the Office of Management and Budget (OMB) Final 
Information Quality Bulletin for Peer Review (M-05-03; December 16, 
2004). The draft status review report was peer reviewed by independent 
specialists selected from the academic and scientific community, with 
expertise in manta ray biology, conservation, and management. The peer 
reviewers were asked to evaluate the adequacy, appropriateness, and 
application of data used in the status review, including the extinction 
risk analysis. All peer reviewer comments were addressed prior to 
dissemination and finalization of the draft status review report and 
publication of this finding.
    We subsequently reviewed the status review report, its cited 
references, and peer review comments, and believe the status review 
report, upon which this 12-month finding and proposed rule is based, 
provides the best available scientific and commercial information on 
the two manta ray species. Much of the information discussed below on 
manta ray biology, distribution, abundance, threats, and extinction 
risk is attributable to the status review report. However, in making 
the 12-month finding determination and proposed rule, we have 
independently applied the statutory provisions of the ESA, including 
evaluation of the factors set forth in section 4(a)(1)(A)-(E) and our 
regulations regarding listing determinations. The status review report 
is available on our Web site (see ADDRESSES section) and the peer 
review report is available at https://www.cio.noaa.gov/services_programs/prplans/PRsummaries.html. Below is a summary of the 
information from the status review report and our analysis of the 
status of the giant manta ray and reef manta ray. Further details can 
be found in Miller and Klimovich (2016).

Description, Life History, and Ecology of the Petitioned Species

Species Description

    Manta rays are large bodied, planktivorous rays, considered part of 
the Mobulidae subfamily that appears to have diverged from Rhinoptera 
around 30 million years ago (Poortvliet et al. 2015). Manta species are 
distinguished from other Mobula rays in that they tend to be larger, 
with a terminal mouth, and have long cephalic fins (Evgeny 2010). The 
genus Manta has a long and convoluted taxonomic history due partially 
to the difficulty of preserving such large specimens and conflicting 
historical reports of taxonomic characteristics (Couturier et al. 2012; 
Kitchen-Wheeler 2013). All manta rays were historically categorized as 
Manta birostris, but Marshall et al. (2009) presented new data that 
supported the splitting of the monospecific Manta genus into two 
species: M. birostris and M. alfredi.
    Both Manta species have diamond-shaped bodies with wing-like 
pectoral fins; the distance over this wingspan is termed disc width 
(DW). There are two distinct color types in both species: chevron and 
black (melanistic). Most of the chevron variants have a black dorsal 
surface and a white ventral surface with distinct patterns on the 
underside that can be used to identify individuals (Marshall et al. 
2008; Kitchen-Wheeler 2010; Deakos et al. 2011). While these markings 
are assumed to be permanent, there is some evidence that the 
pigmentation pattern of M. birostris may actually change over the 
course of development (based on observation of two individuals in 
captivity), and thus caution may be warranted when using color markings 
for identification purposes in the wild (Ari 2015). The black color 
variants of both species are entirely black on the dorsal side and 
almost completely black on the ventral side, except for areas between 
the gill-slits and the abdominal area below the gill-slits (Kitchen-
Wheeler 2013).

Range, Distribution and Habitat Use

    Manta rays are circumglobal in range, but within this broad 
distribution, individual populations are scattered and highly 
fragmented (CITES 2013). The ranges of the two manta species sometimes 
overlap; however, at a finer spatial scale, the two species generally 
appear to be allopatric within those habitat areas (Kashiwagi et al. 
2011) and exhibit different habitat use and movement patterns (inshore 
versus offshore reef habitat use) (Marshall and Bennett 2010b; 
Kashiwagi et al. 2011). Clark (2010) suggests that the larger M. 
birostris may forage in less productive pelagic waters and conduct 
seasonal migrations following prey abundance, whereas M. alfredi is 
more of a resident species in areas with regular coastal productivity 
and predictable prey abundance. Kashiwagi et al. (2010) observed that 
even in areas where both species are found in large numbers at the same 
feeding and cleaning sites, the two species do not interact with each 
other (e.g., they are not part of the same feeding group, and males of 
one species

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do not attempt to mate with females of the other species). Additional 
studies on habitat use for both species are needed, particularly 
investigating how these individuals influence their environment as 
studies have shown that the removal of large plankton feeders, like 
manta rays, from the ecosystem can cause significant changes in species 
composition (Springer et al. 2003).
    The giant manta ray can be found in all ocean basins. In terms of 
range, within the Northern Hemisphere, the species has been documented 
as far north as southern California and New Jersey on the United States 
west and east coasts, respectively, and Mutsu Bay, Aomori, Japan, the 
Sinai Peninsula and Arabian Sea, Egypt, and the Azores Islands (Gudger 
1922; Kashiwagi et al. 2010; Moore 2012; CITES 2013). In the Southern 
Hemisphere, the species occurs as far south as Peru, Uruguay, South 
Africa, New Zealand and French Polynesia (Mourier 2012; CITES 2013). 
Despite this large range, sightings are often sporadic. The timing of 
these sightings also varies by region (for example, the majority of 
sightings in Brazil occur during June and September, while in New 
Zealand sightings mostly occur between January and March) and seems to 
correspond with the movement of zooplankton, current circulation and 
tidal patterns, seawater temperature, and possibly mating behavior 
(Couturier et al. 2012; De Boer et al. 2015; Armstrong et al. 2016).
    Within its range, M. birostris inhabits tropical, subtropical, and 
temperate bodies of water and is commonly found offshore, in oceanic 
waters, and near productive coastlines (Marshall et al. 2009; Kashiwagi 
et al. 2011). As such, giant manta rays can be found in cooler water, 
as low as 19 [deg]C, although temperature preference appears to vary by 
region (Duffy and Abbott 2003; Marshall et al. 2009; Freedman and Roy 
2012; Graham et al. 2012). Additionally, giant manta rays exhibit a 
high degree of plasticity in terms of their use of depths within their 
habitat, with tagging studies that show the species conducting night 
descents of 200-450 m depths (Rubin et al. 2008; Stewart et al. 2016b) 
and capable of diving to depths exceeding 1,000 m (A. Marshall et al. 
unpubl. data 2011 cited in Marshall et al. (2011a)).
    The giant manta ray is considered to be a migratory species, with 
satellite tracking studies using pop-up satellite archival tags 
registering movements of the giant manta ray from Mozambique to South 
Africa (a distance of 1,100 km), from Ecuador to Peru (190 km), and 
from the Yucatan, Mexico, into the Gulf of Mexico (448 km) (Marshall et 
al. 2011a). In a tracking study of six M. birostris individuals from 
off Mexico's Yucatan peninsula, Graham et al. (2012) calculated a 
maximum distance travelled of 1,151 km (based on cumulative straight 
line distance between locations; tag period ranged from 2 to 64 days). 
Similarly, Hearn et al. (2014) report on a tagged M. birostris that was 
tracked from Isla de la Plata (Ecuador) to west of Darwin Island (tag 
was released after 104 days), a straight-line distance of 1,500 km, 
further confirming that the species is capable of fairly long distance 
migrations but also demonstrating connectivity between mainland and 
offshore islands. However, a recent study by Stewart et al. (2016a) 
suggests that the species may not be as highly migratory as previously 
thought. Using pop-up satellite archival tags in combination with 
analyses of stable isotope and genetic data, the authors found evidence 
that M. birostris may actually exist as well-structured subpopulations 
off Mexico's coast that exhibit a high degree of residency (Stewart et 
al. 2016a). Additional research is required to better understand the 
distribution and movement of the species throughout its range.
    In terms of range of the reef manta ray, M. alfredi, the species is 
currently only observed in the Indian Ocean and the western and south 
Pacific. The northern range limit for the species in the western 
Pacific is presently known to be off Kochi, Japan (32[deg]48' N., 
132[deg]58' E.), and its eastern limit in the Pacific is known to be 
Fatu Hiva in French Polynesia (10[deg]29' S.; 138[deg]37' W.) 
(Kashiwagi et al. 2010; Mourier 2012). However, it is difficult to 
estimate the historical range of M. alfredi due to confusion until 
recently about its identification (Marshall et al. 2009). For example, 
prior to the splitting of the genus, it was assumed that all manta rays 
found in the Philippines were M. birostris; however, based on recent 
survey efforts, it has been confirmed that both M. birostris and M. 
alfredi occur in these waters (Verdote and Ponzo 2014; Aquino et al. 
2015; Rambahiniarison et al. 2016). This may be the case elsewhere 
through its range and underscores the need for concentrated survey 
effort in order to better understand the distribution of these two 
manta ray species.
    Manta alfredi is commonly seen inshore near coral and rocky reefs 
and appears to avoid colder waters (<21 [deg]C) (Rohner et al. 2013; 
Braun et al. 2014). Reef manta rays prefer habitats along productive 
nearshore environments (such as island groups or near upwelling 
events), and while recent tracking studies indicate that M. alfredi is 
capable of traveling long distances, similar to M. birostris (Yano et 
al. 1999; Germanov and Marshall 2014), reef manta rays are considered a 
more resident species than giant manta rays (Homma et al. 1999; Dewar 
et al. 2008; Clark 2010; Kitchen-Wheeler 2010; Anderson et al. 2011a; 
Deakos et al. 2011; Marshall et al. 2011b; McCauley et al. 2014), with 
residencies estimated at up to 1.5 years (Clark 2010). For example, 
along the east coast of Australia, mark-recapture methods and 
photographic identification of reef manta rays from 1982 to 2012 
revealed a re-sighting rate of more than 60 percent (with females more 
likely to be re-sighted than males), suggesting high site fidelity to 
aggregation sites, including several locations within a range of up to 
650 km (Couturier et al. 2014). In Hawaii, 76 percent of 105 M. alfredi 
individuals observed over 15 years of surveys were re-sighted along the 
Kona coast, also confirming the high site fidelity behavior of the 
species (Clark 2010). Additionally, predictable seasonal aggregations 
of M. alfredi, largely thought to be feeding-related and influenced by 
the seasonal distribution of prey (Anderson et al. 2011a), have been 
documented off the Maldives (Anderson et al. 2011a), Maui, Hawaii 
(Deakos et al. 2011), Lady Elliott Island, Australia (Couturier et al. 
2014), Ningaloo Reef, Western Australia (McGregor et al. 2008), and 
southern Mozambique (Marshall et al. 2011c; Rohner et al. 2013).

Diet and Feeding

    As previously mentioned, manta feeding habits appear to be 
influenced by the movement and accumulation of zooplankton (Armstrong 
et al. 2016). Both manta species primarily feed on planktonic organisms 
such as euphausiids, copepods, mysids, decapod larvae and shrimp, but 
some studies have noted their consumption of small and moderate sized 
fishes as well (Bertolini 1933; Bigelow and Schroeder 1953; Carpenter 
and Niem 2001; The Hawaii Association for Marine Education and Research 
Inc. 2005). Mantas appear to be primarily nocturnal feeders, consistent 
with the upward migration of zooplankton at night, increasing their 
accessibility (Cushing 1951; Forward 1988). Known manta feeding areas 
that have been reported in the literature are summarized in Table 1 of 
Miller and Klimovich (2016); however, it is likely that additional 
feeding areas exist throughout both species' respective ranges.

[[Page 3698]]

Growth and Reproduction

    Manta rays are viviparous (i.e., give birth to live young), with a 
gestation period of around one year (Matsumoto and Uchida 2008; Uchida 
et al. 2008), and a reproductive periodicity of anywhere from 1 to 5 
years (see Table 3 in Miller and Klimovich (2016)). Generally, not much 
is known about manta ray growth and development. Free swimming wild 
mantas have been observed as small as 1.02 m DW and 1.22 m DW (Kitchen-
Wheeler 2013), with size at birth estimates ranging from 0.9 m DW to 
1.92 m DW (see Tables 2 and 3 in Miller and Klimovich (2016)); however, 
the lack of observations of small manta rays throughout the species' 
respective ranges may indicate that manta rays segregate by size, with 
different habitats potentially used by neonates and juveniles (Deakos 
2010b). While these habitats have yet to be identified, Erdmann (2014) 
presents a hypothesis, based on tagging data of a juvenile M. alfredi 
(~1.5m DW), that mantas likely give birth in protected areas, such as 
lagoons, that provide protection from larger predators.
    In M. alfredi, Deakos (2012) observed that sexual maturity was 
delayed until growth had reached 90 percent of maximum size, pointing 
to large body size providing a reproductive advantage. Deakos (2010) 
concluded that the minimum size at sexual maturity was 3.37 DW for 
female M. alfredi and 2.80 m DW for males in Maui. There is no evidence 
that male size affects mating success of M. alfredi in any way, but 
larger females were observed to have higher rates of pregnancy than 
smaller females (Deakos 2012). Homma et al. (1999) hypothesized that 
age at sexual maturity was 8-13 years in mantas and the data of Uchida 
et al. (2008), Marshall et al. (2011a) and Marshall and Bennett (2010b) 
confirmed this estimate. However, a population of female M. alfredi in 
the Maldives displayed late maturity (15 years or more) and lower 
reproductive rates than previously reported (one pup every five years, 
instead of biennially) (G. Stevens in prep. as cited in CITES (2013)). 
In contrast, Clark (2010) described a rapid transition to maturity for 
M. alfredi in Kona, Hawaii, with estimates of males reaching sexual 
maturity as early as 3-4 years.
    In terms of mating behavior, during courting, manta rays are 
commonly observed engaging in ``mating chains,'' where multiple males 
will pursue a single female. The mating displays can last hours or 
days, with the female swimming rapidly ahead of the males and 
occasionally somersaulting or turning abruptly (Deakos et al. 2011). 
Sexual dimorphism is present in manta rays, with female M. alfredi as 
much as 18 percent larger than males, so it is unlikely that a male 
could force a female to mate against her will (Deakos 2010; Marshall 
and Bennett 2010b). Additionally, males have never been observed to 
compete with each other directly for the attention of the female, so 
these mating chains may function as a kind of endurance rivalry 
(Andersson 1994; Deakos 2012). No copulations have been observed in the 
wild, so it is difficult to determine which males have a mating 
advantage, but this kind of endurance trial usually selects for the 
success of larger males (Andersson and Iwasa 1996; Deakos 2012).
    Although mantas have been reported to live to at least 40 years old 
(Marshall and Bennett 2010b; Marshall et al. 2011b; Kitchen-Wheeler 
2013) with low rates of natural mortality (Couturier et al. 2012), the 
time needed to grow to maturity and the low reproductive rates mean 
that a female will be able to produce only 5-15 pups in her lifetime 
(CITES 2013). Generation time for both species (based on M. alfredi 
life history parameters) is estimated to be 25 years (Marshall et al. 
2011a; Marshall et al. 2011b). Known life history characteristics of M. 
birostris and M. alfredi are summarized in Tables 2 and 3 in Miller and 
Klimovich (2016).

Population Structure

    Since the splitting of the Manta genus, most of the recent research 
has examined the genetic discreteness, phylogeny, and the evolutionary 
speciation in manta rays (Cerutti-Pereyra et al. 2012; Kashiwagi et al. 
2012; Poortvliet et al. 2015). Very few studies have focused on the 
population structure within each species. However, based on genetic 
sampling, photo-identification, and tracking studies, preliminary 
results tend to indicate that reef manta rays exist in isolated and 
potentially genetically divergent populations. For example, using 
genetic sequencing of mitochondrial DNA (which is maternally-inherited) 
Cerutti-Pereyra et al. (2012) found low genetic divergence (<1 percent) 
but ``phylogeographic disjunction'' between the M. alfredi samples from 
Australia (n = 2; Ningaloo Reef) and Indonesia (n = 2), suggesting 
biogeographic factors may be responsible for population differentiation 
within the species. Although based on very few samples (4 total), these 
findings are consistent with photo-identification and tracking studies, 
which suggest high site-fidelity and residency for M. alfredi in many 
portions of its range, including Indonesia, Ningaloo Reef, Hawaii, 
Fiji, New Caledonia, and eastern Australia (Dewar et al. 2008; Clark 
2010; Couturier et al. 2011; Deakos et al. 2011; Cerutti-Pereyra et al. 
2012; Couturier et al. 2014).
    The population structure for the wider-ranging M. birostris is less 
clear. While Clark (2010), using photo-identification survey data 
collected between 1992 and 2007 along the Kona, Hawaii, coast, found 
low site-fidelity for M. birostris and high rate of immigration, 
indicative of a population that is pelagic rather than coastal or 
island-associated, Stewart et al. (2016a) provided recent evidence to 
show that the giant manta rays off Pacific Mexico may exist as isolated 
subpopulations, with distinct home ranges. Additionally, researchers 
are presently investigating whether there is a potential third manta 
ray species resident to the Yucat[aacute]n coastal waters of the Gulf 
of Mexico (previously identified as M. birostris) (Hinojosa-Alvarez et 
al. 2016). Using the mitochondrial ND5 region (maternally-inherited 
DNA), Hinojosa-Alvarez et al. (2016) found shared haplotypes between 
Yucat[aacute]n manta ray samples and known M. birostris samples from 
Mozambique, Indonesia, Japan, and Mexico, but discovered four new manta 
ray haplotypes, exclusive to the Yucat[aacute]n samples. While analysis 
using the nuclear RAG1 gene (bi-parentally-inherited DNA) showed the 
Yucat[aacute]n samples to be consistent with identified M. birostris 
samples, the authors suggest that the ND5 genetic evidence indicates 
the potential for a third, distinctive manta genetic group or possibly 
M. birostris subspecies. At this time, additional studies, including 
in-depth taxonomic studies and additional genetic sampling, are needed 
to better understand the population structure of both species 
throughout their respective ranges.

Population Demographics

    Given their large sizes, manta rays are assumed to have fairly high 
survival rates after maturity (e.g., low natural predation rates). 
Using estimates of known life history parameters for both giant and 
reef manta rays, and plausible range estimates for the unknown life 
history parameters, Dulvy et al. (2014) calculated a maximum population 
growth rate of Manta spp. and found it to be one of the lowest values 
when compared to 106 other shark and ray species. After taking into 
consideration different model assumptions, and the criteria for 
assessing productivity in Musick (1999), Dulvy et al. (2014) estimated 
realized productivity (r) for manta rays to be 0.029 (Dulvy et al.

[[Page 3699]]

2014). This value is similar to the productivity estimate from 
Kashiwagi (2014) who empirically determined an r value of 0.023 using 
capture-mark-recapture analyses. Ward-Paige et al. (2013) calculated 
slightly higher estimates for the intrinsic rate of population 
increase, with r = 0.05 for M. alfredi and r = 0.042 for M. birostris; 
however, these estimates still place both manta ray species into or at 
the very edge of the ``very low'' productivity category (r <0.05), 
based on the productivity parameters and criteria in Musick (1999).
    In order to determine how changes in survival may affect 
populations, Smallegange et al. (2016) modeled the demographics of reef 
manta rays. Results showed that increases in yearling or adult annual 
survival rates resulted in much greater responses in population growth 
rates, mean lifetime reproductive success, and cohort generation time 
compared to similar increases in juvenile annual survival rates 
(Smallegange et al. 2016). Based on the elasticity analysis, population 
growth rate was most sensitive to changes in the survival rate of 
adults (Smallegange et al. 2016). In other words, in order to prevent 
populations from declining further, Smallegange et al. (2016) found 
that adult survival rates should be increased, such as through 
protection of adult aggregation sites or a reduction in fishing of 
adult manta rays (Smallegange et al. 2016). For those populations that 
are currently stable, like the Yaeyama Islands (Japan) population 
(where adult annual survival rate is estimated at 0.95; noted above), 
Smallegange et al. (2016) note that any changes in adult survival may 
significantly affect the population.
    Overall, given their life history traits and productivity 
estimates, particularly their low reproductive output and sensitivity 
to changes in adult survival rates, giant and reef manta ray 
populations are inherently vulnerable to depletions, with low 
likelihood of recovery.

Historical and Current Distribution and Population Abundance

    There are no current or historical estimates of the global 
abundance of M. birostris. Despite their larger range, they are 
encountered with less frequency than M. alfredi. Most estimates of 
subpopulations are based on anecdotal diver or fisherman observations, 
which are subject to bias. These populations seem to potentially range 
from around 100 to1,500 individuals (see Table 4 in Miller and 
Klimovich (2016)). In the proposal to include manta rays on the 
appendices of the Convention on International Trade in Endangered 
Species of Wild Fauna and Flora (CITES), it states that because 10 
populations of M. birostris have been actively studied, 25 other 
aggregations have been anecdotally identified, and all other sightings 
are rare, the total global population may be small (CITES 2013). The 
greatest number of M. birostris identified in the four largest known 
aggregation sites ranges from 180 to 1,500. Ecuador is thought to be 
home to the largest identified population of M. birostris in the world, 
with large aggregation sites within the waters of the Machalilla 
National Park and the Galapagos Marine Reserve (Hearn et al. 2014). 
Within the Indian Ocean, numbers of giant manta rays identified through 
citizen science in Thailand's waters (primarily on the west coast, off 
Khao Lak and Koh Lanta) have been increasing over the past few years, 
from 108 in 2015 to 288 in 2016. These numbers reportedly surpass the 
estimate of identified giant mantas in Mozambique (n = 254), possibly 
indicating that Thailand may be home to the largest aggregation of 
giant manta rays within the Indian Ocean (MantaMatcher 2016). In the 
Atlantic, very little information on M. birostris populations is 
available, but there is a known, protected population within the Flower 
Garden Banks National Marine Sanctuary in the Gulf of Mexico. However, 
researchers are still trying to determine whether the manta rays in 
this area are only M. birostris individuals or potentially also 
comprise individuals of a new, undescribed species (Marshall et al. 
2009; Hinojosa-Alvarez et al. 2016).
    In areas where the species is not subject to fishing, populations 
may be stable. For example, Rohner et al. (2013) report that giant 
manta ray sightings remained constant off the coast of Mozambique over 
a period of 8 years. However, in regions where giant manta rays are (or 
were) actively targeted or caught as bycatch, such as the Philippines, 
Mexico, Sri Lanka, and Indonesia, populations appear to be decreasing 
(see Table 5 in Miller and Klimovich (2016)). In Indonesia, declines in 
manta ray landings are estimated to be on the order of 71 to 95 
percent, with potential extirpations noted in certain areas (Lewis et 
al. 2015). Given the migratory nature of the species, population 
declines in waters where mantas are protected have also been observed 
but attributed to overfishing of the species in adjacent areas within 
its large home range. For example, White et al. (2015) provide evidence 
of a substantial decline in the M. birostris population in Cocos Island 
National Park, Costa Rica, where protections for the species have 
existed for over 20 years. Using a standardized time series of 
observations collected by dive masters on 27,527 dives conducted from 
1993 to 2013, giant manta ray relative abundance declined by 
approximately 89 percent. Based on the frequency of the species' 
presence on dives (4 percent), with a maximum of 15 individuals 
observed on a single dive, the authors suggest that Cocos Island may 
not be a large aggregating spot for the species, and suggest that the 
decline observed in the population is likely due to overfishing of the 
species outside of the National Park (White et al. 2015).
    Given that all manta rays were identified as M. birostris prior to 
2009, information on the historical abundance and distribution of M. 
alfredi is scarce. In the proposal to include the reef manta ray on the 
appendices of the Convention on the Conservation of Migratory Species 
of Wild Animals (CMS), it states that current global population numbers 
are unknown and no historical baseline data exist (CMS 2014). Local 
populations of M. alfredi have not been well assessed either, but 
appear generally to be small, sparsely distributed, and isolated. 
Photo-identification studies in Hawaii, Yap, Japan, Indonesia, and the 
eastern coast of Australia suggest these subpopulations range from 100 
to 350 individuals (see Table 6 in Miller and Klimovich (2016)), 
despite observational periods that span multiple decades. However, in 
the Maldives, population estimates range from 3,300 to 9,677 
individuals throughout the 26 atolls in the archipelago (Kitchen-
Wheeler et al. 2012; CITES 2013; CMS 2014), making it the largest 
identified population of M. alfredi in the world. Other larger 
populations may exist off southern Mozambique (superpopulation estimate 
of 802-890 individuals; Rohner et al. (2013); CITES (2013)) and Western 
Australia (metapopulation estimate = 1,200-1,500; McGregor (2009) cited 
in CITES (2013)).
    In terms of trends, studies report that the rate of population 
reduction appears to be high in local areas, from 50-88 percent, with 
areas of potential local extirpations of M. alfredi populations (Homma 
et al. 1999; Rohner et al. 2013; Lewis et al. 2015). In the portions of 
range where reef manta rays are experiencing anthropogenic pressures, 
including Indonesia and Mozambique, encounter rates have dropped 
significantly over the last 5 to 10 years (CMS 2014). However, where M. 
alfredi receives some kind of protection, such as in Australia, Hawaii, 
Guam, Japan,

[[Page 3700]]

the Maldives, Palau, and Yap, CITES (2013) reports that subpopulations 
are likely to be stable. For example, in Hawaii, based on photo-
identification survey data collected between 1992 and 2007 along the 
Kona Coast, Clark (2010) used a discovery curve to estimate that an 
average of 4.27 new pups were entering the population per year. Off the 
Yaeyama Islands, Japan, Kashiwagi (2014) conducted quantitative 
analyses using encounter records, biological observations, and photo-ID 
of manta rays over the period of 1987 to 2009 and found that the 
apparent population size increased steadily but slowly over the 23-year 
period, with a population growth rate estimate of 1.02-1.03. Based on 
aerial surveys of Guam conducted from 1963 to 2012, manta ray 
observations were infrequent but showed an increase over the study 
period (Martin et al. 2015). Off Lady Elliott Island, Australia, 
Couturier et al. (2014) modeled annual population sizes of M. alfredi 
from 2009 to 2012 and found an annual increase in abundance for both 
sexes, but cautioned that the modeled increase could be an artifact of 
improvements in photo-identification by observers over the study 
period. Within Ningaloo Marine Park, the status of reef manta rays was 
assessed as ``Good'' in 2013, but with low confidence in the ratings 
(Marine Parks & Reserves Authority 2013). Overall, however, the reef 
manta ray population of Australia is deemed to be one of the world's 
healthiest (Australian Government 2012).

Species Finding

    Based on the best available scientific and commercial information 
described above, we find that M. birostris and M. alfredi are currently 
considered taxonomically-distinct species and, therefore, meet the 
definition of ``species'' pursuant to section 3 of the ESA. Below, we 
evaluate whether these species warrant listing as endangered or 
threatened under the ESA throughout all or a significant portion of 
their respective range.

Summary of Factors Affecting Giant and Reef Manta Rays

    As described above, section 4(a)(1) of the ESA and NMFS' 
implementing regulations (50 CFR 424.11(c)) state that we must 
determine whether a species is endangered or threatened because of any 
one or a combination of the following factors: The present or 
threatened destruction, modification, or curtailment of its habitat or 
range; overutilization for commercial, recreational, scientific, or 
educational purposes; disease or predation; inadequacy of existing 
regulatory mechanisms; or other natural or man-made factors affecting 
its continued existence. We evaluated whether and the extent to which 
each of the foregoing factors contribute to the overall extinction risk 
of both manta ray species, with a ``significant'' contribution defined, 
for purposes of this evaluation, as increasing the risk to such a 
degree that the factor affects the species' demographics (i.e., 
abundance, productivity, spatial structure, diversity) either to the 
point where the species is strongly influenced by stochastic or 
depensatory processes or is on a trajectory toward this point. This 
section briefly summarizes our findings and conclusions regarding 
threats to the giant and reef manta rays and their impact on the 
overall extinction risk of the species. More details can be found in 
the status review report (Miller and Klimovich 2016).

The Present or Threatened Destruction, Modification, or Curtailment of 
Its Habitat or Range

    Due to their association with nearshore habitats, manta rays are at 
elevated risk for exposure to a variety of contaminants and pollutants, 
including brevotoxins, heavy metals, polychlorinated biphenyls, and 
plastics. Many pollutants in the environment have the ability to 
bioaccumulate in fish species; however, only a few studies have 
specifically examined the accumulation of heavy metals in the tissues 
of manta rays (Essumang 2010; Ooi et al. 2015), with findings that 
discuss human health risks from the consumption of manta rays. For 
example, Essumang (2010) found platinum levels within M. birostris 
samples taken off the coast of Ghana that exceeded the United Kingdom 
(UK) dietary intake recommendation levels, and Ooi et al. (2015) 
reported concentrations of lead in M. alfredi tissues from Lady Elliot 
Island, Australia, that exceeded maximum allowable level 
recommendations for fish consumption per the European Commission and 
the Codex Alimentarius Commission (WHO/FAO). While consuming manta rays 
may potentially pose a health risk to humans, there is no information 
on the lethal concentration limits of these metals or other toxins in 
manta rays. Additionally, at this time, there is no evidence to suggest 
that current concentrations of these environmental pollutants are 
causing detrimental physiological effects to the point where either 
species may be at an increased risk of extinction.
    Plastics within the marine environment may also be a threat to the 
manta ray species, as the animals may ingest microplastics (through 
filter-feeding) or become entangled in plastic debris, potentially 
contributing to increased mortality rates. Jambeck et al. (2015) found 
that the Western and Indo-Pacific regions are responsible for the 
majority of plastic waste. These areas also happen to overlap with some 
of the largest known aggregations for manta rays. For example, in 
Thailand, where recent sightings data have identified over 288 giant 
manta rays (MantaMatcher 2016), mismanaged plastic waste is estimated 
to be on the order of 1.03 million tonnes annually, with up to 40 
percent of this entering the marine environment (Jambeck et al. 2015). 
Approximately 1.6 million tonnes of mismanaged plastic waste is being 
disposed of in Sri Lanka, again with up to 40 percent entering the 
marine environment (Jambeck et al. 2015), potentially polluting the 
habitat used by the nearby Maldives aggregation of manta rays. While 
the ingestion of plastics is likely to negatively impact the health of 
the species, the levels of microplastics in manta ray feeding grounds 
and frequency of ingestion are presently being studied to evaluate the 
impact on these species (Germanov 2015b; Germanov 2015a).
    Because manta rays are migratory and considered ecologically 
flexible (e.g., low habitat specificity), they may be less vulnerable 
to the impacts of climate change compared to other sharks and rays 
(Chin et al. 2010). However, as manta rays frequently rely on coral 
reef habitat for important life history functions (e.g., feeding, 
cleaning) and depend on planktonic food resources for nourishment, both 
of which are highly sensitive to environmental changes (Brainard et al. 
2011; Guinder and Molinero 2013), climate change is likely to have an 
impact on the distribution and behavior of both M. birostris and M. 
alfredi. Currently, coral reef degradation from anthropogenic causes, 
particularly climate change, is projected to increase through the 
future. Specifically, annual, globally averaged surface ocean 
temperatures are projected to increase by approximately 0.7 [deg]C by 
2030 and 1.4 [deg]C by 2060 compared to the 1986-2005 average (IPCC 
2013), with the latest climate models predicting annual coral bleaching 
for almost all reefs by 2050 (Heron et al. 2016). As declines in coral 
cover have been shown to result in changes in coral reef fish 
communities (Jones et al. 2004; Graham et al. 2008), the projected 
increase in coral habitat degradation may potentially lead to a

[[Page 3701]]

decrease in the abundance of manta ray cleaning fish (e.g., Labroides 
spp., Thalassoma spp., and Chaetodon spp.) and an overall reduction in 
the number of cleaning stations available to manta rays within these 
habitats. This potential decreased access to cleaning stations may 
negatively impact the fitness of the mantas by hindering their ability 
to reduce parasitic loads and dead tissue, which could lead to 
increases in diseases and declines in reproductive fitness and survival 
rates. However, these scenarios are currently speculative, as there is 
insufficient information to indicate how and to what extent changes in 
reef community structure will affect the status of both manta ray 
species.
    Changes in climate and oceanographic conditions, such as 
acidification, are also known to affect zooplankton structure (size, 
composition, diversity), phenology, and distribution (Guinder and 
Molinero 2013). As such, the migration paths and locations of both 
resident and seasonal aggregations of manta rays, which depend on these 
animals for food, may similarly be altered (Australian Government 2012; 
Couturier et al. 2012). It is likely that those M. alfredi populations 
that exhibit site-fidelity behavior will be most affected by these 
changes. For example, resident manta ray populations may be forced to 
travel farther to find available food or randomly search for new 
productive areas (Australian Government 2012; Couturier et al. 2012). 
As research to understand the exact impacts of climate change on marine 
phytoplankton and zooplankton communities is still ongoing, the 
severity of this threat to both species of manta rays has yet to be 
fully determined.

Overutilization for Commercial, Recreational, Scientific or Educational 
Purposes

    Manta rays are both targeted and caught as bycatch in fisheries 
worldwide. In fact, according to Lawson et al. (2016), manta ray 
catches have been recorded in at least 30 large and small-scale 
fisheries covering 25 countries. The majority of fisheries that target 
mobulids are artisanal (Croll et al. 2015) and target the rays for 
their meat; however, since the 1990s, a market for mobulid gill rakers 
has significantly expanded, increasing the demand for manta ray 
products, particularly in China. The gill rakers of mobulids are used 
in Asian medicine and are thought to have healing properties, such as 
curing diseases from chicken pox to cancer, boosting the immune system, 
purifing the body, enhancing blood circulation, remedying throat and 
skin ailments, curing male kidney issues, and helping with fertility 
problems (Heinrichs et al. 2011). The use of gill rakers as a remedy, 
which was widespread in Southern China many years ago, has recently 
gained renewed popularity over the past decade as traders have 
increased efforts to market its healing and immune boosting properties 
directly to consumers (Heinrichs et al. 2011). As a result, demand has 
significantly increased, incentivizing fishermen who once avoided 
capture of manta rays to directly target these species (Heinrichs et 
al. 2011; CITES 2013). According to Heinrichs et al. (2011), it is 
primarily the older population in Southern China as well as Macau, 
Singapore, and Hong Kong, that ascribes to the belief of the healing 
properties of the gill rakers; however, unlike products like shark 
fins, the gill rakers are not considered ``traditional'' or 
``prestigious'' items and many consumers and sellers are not even aware 
that gill rakers come from manta or mobula rays. Meat, cartilage, and 
skin of manta rays are also utilized, but valued significantly less 
than the gill rakers, and usually enter local trade or are kept for 
domestic consumption (Heinrichs et al. 2011; CITES 2013). Indonesia, 
Sri Lanka, and India presently represent the largest manta ray 
exporting range state countries; however, Chinese gill plate vendors 
have also reported receiving mobulid gill plates from other countries 
and regions as well, including Malaysia, Vietnam, South Africa, South 
America, the Middle East, and the South China Sea (CMS 2014). To 
examine the impact of this growing demand for gill rakers on manta ray 
populations, information on landings and trends (identified by species 
where available) are evaluated for both fisheries that target mantas 
and those that catch mantas as bycatch.
Targeted Fisheries
    Indonesia is reported to be one of the countries that catch the 
most mobulid rays (Heinrichs et al. 2011). Manta and mobula ray 
fisheries span the majority of the Indonesian archipelago, with most 
landing sites along the Indian Ocean coast of East and West Nusa 
Tenggara and Java (Lewis et al. 2015). Manta rays (presumably M. 
birostris, but identified prior to the split of the genus) have 
traditionally been harvested in Indonesia using harpoons and boats 
powered by paddles or sails, with manta fishing season lasting from May 
through October. Historically, the harvested manta rays would be 
utilized by the village, but the advent of the international gill raker 
market in the 1970s prompted the commercial trade of manta ray 
products, with gill plates generally sent to Bali, Surabaya (East 
Java), Ujung Pandant (Sulawasi), or Jakarta (West Java) for export to 
Hong Kong, Taiwan, Singapore and other places in Asia (Dewar 2002; 
White et al. 2006; Marshall and Conradie 2014). This economic 
incentive, coupled with emerging technological advances (e.g., 
motorized vessels) and an increase in the number of boats in the 
fishery, greatly increased fishing pressure and harvest of manta rays 
in the 1990s and 2000s (Dewar 2002). In Lamakera, Indonesia, one of the 
main landing sites for mobulids, and particularly manta rays, Dewar 
(2002) estimates that the total average harvest of ``mantas'' during 
the 2002 fishing season was 1,500 individuals (range 1,050-2,400), 
which is a significant increase from the estimated historical harvest 
levels of around 200-300 mantas per season. However, Lewis et al. 
(2015) note that this estimate likely represents all mobulid rays, not 
just manta rays.
    However, given these amounts, it is perhaps unsurprising that 
anecdotal reports from fishermen indicate possible local population 
declines, with fishermen noting that they have to travel farther to 
fishing grounds as manta rays are no longer present closer to the 
village (Dewar 2002; Lewis et al. 2015). In fact, using the records 
from Dewar (2002) and community (local) catch records, Lewis et al. 
(2015) show that there has been a steady decline in manta landings at 
Lamakera since 2002 (despite relatively unchanged fishing effort), with 
estimated landings in 2013-2014 comprising only 25 percent of the 
estimated numbers from 2002-2006. These declines in manta landings are 
not just limited to Lamakera, but also appear to be the trend 
throughout Indonesia at the common mobulid landing sites. For example, 
Lewis et al. (2015) reports a 95 percent decline in manta landings in 
Tanjung Luar (between 2001-2005 and 2013-2014), a decrease in the 
average size of mantas being caught, and a 71 percent decline in manta 
landings in the Cilacap gillnet fishery between 2001-2005 and 2014. 
Areas in Indonesia where manta rays have potentially been fished to 
extirpation, based on anecdotal reports (e.g., diver sightings data and 
fishermen interviews), include Lembeh Strait in northeast Sulawesi, 
Selayer Islands in South Sulawesi, and off the west coast of Alor 
Island (which may have been a local M. alfredi population) (Lewis et 
al. 2015).
    Although fishing for manta rays was banned within the Indonesian 
exclusive economic zone (EEZ) in February 2014

[[Page 3702]]

(see The Inadequacy of Existing Regulatory Mechanisms), in May 2014, 
manta rays were still being caught and processed at Lamakera, with M. 
birostris the most commonly targeted species (Marshall and Conradie 
2014). Around 200 fishing vessels targeting mantas rays are in 
operation (Marshall and Conradie 2014). Most of the fishing occurs in 
the Solor Sea and occasionally in the Lamakera Strait, with landings 
generally comprising around one to two dozen manta rays per day. Taking 
into account the manta ray fishing season in Lamakera (June to 
October), Marshall and Conradie (2014) estimate that between 625 and 
3,125 manta rays (likely majority M. birostris) may be landed each 
season. Lewis et al. (2015), however, report a much smaller number, 
with 149 estimated as landed in 2014.
    It is unlikely that fishing effort and associated utilization of 
the species will significantly decrease in the foreseeable future 
because interviews with fishermen indicate that many are excited for 
the new prohibition on manta rays in Indonesian waters, as it is 
expected to drive up the price of manta ray products and significantly 
increase the current income of resident fishermen (Marshall and 
Conradie 2014). Based on unpublished data, O'Malley et al. (2013) 
estimate that the total annual income from the manta ray fisheries in 
Indonesia is around $442,000 (with 94 percent attributed to the gill 
plate trade). Dharmadi et al. (2015) noted that there are still many 
fishermen, particularly in Raja Ampat, Bali, and Komodo, whose 
livelihoods depend on shark and ray fishing. Without an alternative for 
income, it is unlikely that these fishing villages will stop their 
traditional fishing practices. Additionally, enforcement of existing 
laws appears to be lacking in this region (Marshall and Conradie 2014). 
The high market prices for manta products, where a whole manta (~5 m 
DW) will sell for anywhere from $225-$450 (Lewis et al. 2015), drives 
the incentive to continue fishing the species, and evidence of 
continued targeted fishing despite prohibitions suggests that 
overutilization of the Indonesian manta ray populations (primarily M. 
birostris, based on the data) is likely to continue to occur into the 
foreseeable future.
    In the Philippines, fishing for manta rays mainly occurs in the 
Bohol Sea. According to Acebes and Tull (2016), the manta ray fishery 
can be divided into two distinct periods based on technology and 
fishing effort: (1) 1800s to 1960s, when mantas were mainly hunted in 
small, non-motorized boats using harpoons from March to May; and (2) 
1970s to 2013 (present), when boats became bigger and motorized and the 
fishing technique switched to drift gillnets, with the manta hunting 
season extending from November to June. In the earlier period, the 
manta fishing grounds were fairly close to the shore (<5 km), noted 
along the coasts of southern Bohol, northwestern and southern coasts of 
Camiguin and eastern coasts of Limasawa. Boats would usually catch 
around one manta per day, with catches of 5-10 mantas for a fishing 
village considered a ``good day'' (Acebes and Tull 2016). As the 
fishery became more mechanized in the 1970s, transitioning to larger 
and motorized boats, and as the primary gear changed from harpoons to 
non-selective driftnets, fishermen were able to access previously 
unexplored offshore fishing grounds, stay out for longer periods of 
time, and catch more manta rays (Acebes and Tull 2016). Additionally, 
it was during this time that the international gill raker market opened 
up, increasing the value of gill rakers, particularly for manta 
species. By 1997, there were 22 active mobulid ray fishing sites in the 
Bohol Sea (Acebes and Tull 2016). In Pamilacan, 18 boats were fishing 
for mobulids in 1993, increasing to 40 by 1997, and in Jagna, at least 
20 boats were engaged in mobulid hunting in the 1990s (Acebes and Tull 
2016). Catches from this time period, based on the recollection of 
fishermen from Pamilacan and Baclayon, Bohol, were around 8 manta rays 
(for a single boat) in 1995 and 50 manta rays (single boat) in 1996 
(Alava et al. 2002). However, it should be noted that the mobulid 
fishery ended in Lila and Limasawa Island in the late 1980s and in 
Sagay in 1997, around the time that the whale fishery closed and a 
local ban in manta ray fishing was imposed (Acebes and Tull 2016).
    Despite increases in fishing effort, catches of manta rays began to 
decline in Philippine waters, likely due to a decrease in the abundance 
of the population, prompting fishermen to shift their fishing grounds 
farther east and north. Although a ban on hunting and selling giant 
manta rays was implemented in the Philippines in 1998 (see The 
Inadequacy of Existing Regulatory Mechanisms), this has not seemed to 
impact the mobulid fishery in any way. In Pamilacan, there were 14 
mobulid hunting boats reported to be in operation in 2011 (Acebes and 
Tull 2016). In the village of Bunga Mar, Bohol, there were 15 boats 
targeting mobulids in 2012, and out of 324 registered fishermen, over a 
third were actively engaged in ray fishing (Acebes and Tull 2016). 
Acebes and Tull (2016) monitored the numbers of manta rays landed at 
Bunga Mar over a period of 143 days from April 2010 to December 2011 
(during which there were around 16-17 active fishing boats targeting 
mobulids), and in total, 40 M. birostris were caught. In 2013, records 
from a single village (location not identified) showed over 2,000 
mobuilds landed from January to May, of which 2 percent (n = 51 
individuals) were M. birostris (Verdote and Ponzo 2014). As there is 
little evidence of enforcement of current prohibitions on manta ray 
hunting, and no efforts to regulate the mobulid fisheries, with mobulid 
fishing providing the greatest profit to fishermen, it is unlikely that 
fishing for mantas, of which the majority appears to be M. birostris, 
will decrease in the future.
    Manta rays are also reportedly targeted in fisheries in India, 
Ghana, Peru, Thailand, Mozambique, Tonga, Micronesia, possibly the 
Republic of Maldives, and previously in Mexico. In India, Ghana, Peru, 
and Thailand, little information is available on the actual level of 
take of manta rays. In India, manta rays are mainly landed as bycatch 
in tuna gillnetting and trawl fisheries; however, a harpoon fishery at 
Kalpeni, off Lakshadweep Islands, is noted for ``abundantly'' landing 
mantas (likely M. alfredi; A.M. Kitchen-Wheeler pers. comm. 2016) 
during peak season (from June-August) (Raje et al. 2007). In Ghana, 
there is no available data on the amount of manta rays landed in 
Ghanaian fisheries; however, Debrah et al. (2010) observed that giant 
manta rays were targeted using wide-mesh drift gillnets in artisanal 
fisheries between 1995 and 2010, and D. Berces (pers. comm. 2016) 
confirmed that manta rays are taken during artisanal fishing for 
pelagic sharks, and not ``infrequently,'' with manta rays consumed 
locally. In Peru, Heinrichs et al. (2011), citing to a rapid assessment 
of the mobulid fisheries in the Tumbes and Piura regions, reported 
estimated annual landings of M. birostris on the order of 100-220 manta 
rays for one family of fishermen. As such, total landings for Peru are 
likely to be much larger. According to Heinrichs et al. (2011), dive 
operators in the Similan Islands, Thailand, have also observed an 
increase in fishing for manta rays, including in protected Thai 
national marine parks, and while information on catches is unavailable, 
sightings of Manta spp. (likely M. birostris) decreased by 76 percent 
between 2006 and 2012 (CITES 2013b).
    In southern Mozambique, reef manta rays are targeted by fishermen, 
with

[[Page 3703]]

estimates of around 20-50 individuals taken annually from only a 50 km 
section of studied coastline (Rohner et al. 2013). As annual estimates 
of this M. alfredi population range only from 149 to 454 individuals 
(between 2003 and 2007), this take is equivalent to removing anywhere 
from 4 percent to 34 percent of the population per year. This removal 
rate is potentially unsustainable for a species with such a low 
productivity, and has likely contributed to the estimated 88 percent 
decline that has already been observed in the local reef manta ray 
population (Rohner et al. 2013). Manta birostris, on the other hand, 
has not exhibited a decline off Mozambique, represents only 21 percent 
of the identified manta rays in this area, and is rarely observed in 
the local fishery (one observed caught over an 8-year period), 
indicating that fishing pressure is likely low for this species (Rohner 
et al. 2013; Marine Megafauna Foundation 2016).
    Opportunistic hunting of manta rays (likely M. alfredi) has been 
reported in Tonga and Micronesia (B. Newton and J. Hartup pers. comms. 
cited in CMS 2014), and in the Maldives, Anderson and Hafiz (2002) note 
that very small catches of manta rays occur in the traditional 
fisheries, with meat used for bait for shark fishing and skin used for 
musical drums. Given the available information, it is unlikely that 
fishing pressure on either manta ray species is significant in these 
areas.
    In Mexico, giant manta rays and mobula rays were historically 
targeted for their meat in the Gulf of California. In 1981, 
Notarbartolo di Sciara (1988) observed a seasonally-active mobulid 
fishery located near La Paz, Baja California Sur. Mobulids were fished 
in the Gulf of California using both gillnets and harpoons, with their 
meat either fileted for human consumption or used as shark bait. The 
giant manta ray was characterized as ``occasionally captured'' by the 
fishery, and while it is unclear how abundant M. birostris was in this 
area, by the early 1990s, Homma et al. (1999) reported that the entire 
mobulid fishery had collapsed.
Bycatch
    Given the global distribution of manta rays, they are frequently 
caught as bycatch in a number of commercial and artisanal fisheries 
worldwide. In a study of elasmobranch bycatch patterns in commercial 
longline, trawl, purse seine and gillnet fisheries, Oliver et al. 
(2015) presented information on species-specific composition of ray 
bycatch in 55 fisheries worldwide. Based on the available data, Oliver 
et al. (2015) found that manta rays comprised the greatest proportion 
of ray bycatch in the purse seine fisheries operating in the Indian 
Ocean (specifically M. birostris; ~40 percent) and especially the 
Eastern Pacific Ocean (identified as Manta spp.; ~100 percent, but 
would be M. birostris as well), but were not large components of the 
ray bycatch in the longline, trawl, or gillnet fisheries in any of the 
ocean basins.
    In the Atlantic Ocean, bycatch of giant manta rays has been 
observed in purse seine, trawl, and longline fisheries; however, M. 
birostris does not appear to be a significant component of the bycatch. 
For example, in the European purse seine fishery, which primarily 
operates in the Eastern Atlantic off western Africa, observer data 
collected over the period of 2003-2007 (27 trips, 598 sets; observer 
coverage averaged 2.93 percent) showed only 11 M. birostris caught, 
with an equivalent weight of 2.2 mt (Amand[egrave] et al. 2010). In the 
U.S. bottom longline and gillnet fisheries operating in the western 
Atlantic, M. birostris is also a very rare occurrence in the 
elasmobranch catch, with the vast majority that are caught released 
alive (see NMFS Reports available at https://www.sefsc.noaa.gov/labs/panama/ob/bottomlineobserver.htm and https://www.sefsc.noaa.gov/labs/panama/ob/gillnet.htm). Overall, given the present low fishing pressure 
on giant manta rays, and evidence of minimal bycatch of the species 
(see Miller and Klimovich (2016) for additional discussion), it is 
unlikely that overutilization as a result of bycatch mortality is a 
significant threat to M. birostris in the Atlantic Ocean. However, 
information is severely lacking on both population sizes and 
distribution of the giant manta ray as well as current catch and 
fishing effort on the species throughout this portion of its range.
    In the Indian Ocean, manta rays (primarily M. birostris) are mainly 
caught as bycatch in purse seine and gillnet fisheries. In the western 
Indian Ocean, data from the pelagic tuna purse seine fishery suggests 
that manta and mobula rays, together, are an insignificant portion of 
the bycatch, comprising less than one percent of the total non-tuna 
bycatch per year (Romanov 2002; Amand[egrave] et al. 2008). However, in 
the eastern Indian Ocean, manta rays appear at higher risk of capture 
from the fisheries operating throughout this area, with two of the top 
three largest Manta spp. fishing and exporting range states (Sri Lanka 
and India) located in this region (Heinrichs et al. 2011). In Sri 
Lanka, manta rays are primarily caught as bycatch in the artisanal 
gillnet fisheries. While fishermen note that they generally tend to 
avoid deploying nets near large aggregations of manta rays or regularly 
release them when caught, as recently as 2011, giant manta rays were 
observed being sold at Sri Lanka fish markets (Fernando and Stevens 
2011). Additionally, although Sri Lankan fishermen state that they try 
to release pregnant and young manta rays alive, based on 40 observed M. 
birostris being sold at markets (from May through August 2011), 95 
percent were juveniles or immature adults (Fernando and Stevens 2011). 
Extrapolating the observed market numbers to a yearly value, Fernando 
and Stevens (2011) estimated total annual landings for M. birostris in 
Sri Lanka to be around 1,055 individuals, which they concluded would 
likely result in a population crash (Fernando and Stevens 2011). 
Additionally, more recent data from the Indian Ocean Tuna Commission 
(IOTC) database (https://www.iotc.org/iotc-online-data-querying-service) 
covering the time period of 2012-2014 indicate that over 2,400 mt of M. 
birostris were recorded caught by the Sri Lankan gillnet and longline 
fleets primarily engaged in artisanal fishing. This amount is almost 
double the 1,413 mt total catch that was reported in Clarke and IOTC 
Secretariat (2014) by both Sri Lanka and Sudan fleets from a time 
period that was more than twice as long (2008-2013). Using the maximum 
observed weight of M. birostris in the Indian Ocean (2,000 kg; which 
was described as ``unusually large'' (Kunjipalu and Boopendranath 
1982)), this translates to a minimum of around 400 giant manta rays 
caught annually in recent years by Sri Lankan fishing fleets. Given 
that fishermen have already noted a decrease in catches of manta rays 
over the past 5 years, it is likely that the continued and heavy 
fishing pressure on M. birostris, and associated bycatch mortality, is 
significantly contributing to the overutilization of the species in 
this portion of its range.
    Manta ray landings have also become a more common occurrence in the 
bycatch of fishermen operating off India. Here, mobulids, including 
mantas, are landed as bycatch during tuna gillnetting and trawling 
operations and are auctioned off for their gill plates, while the meat 
enters the local markets. Historical reports (from 1961-1995) indicate 
that manta rays were only sporadically caught by fishermen along the 
east and west coasts of India, likely due to the fact that the species 
was rarely found near the shore (Pillai 1998). However, based on 
available information, it appears that landings

[[Page 3704]]

have increased in recent years, particularly on the southwest coast. 
For the years 2003 and 2004, Raje et al. (2007) reported 647 mt of M. 
birostris from the southwest coast of India by the trawl fisheries. In 
a snapshot of the Indian tuna gillnet fishery, Nair et al. (2013) 
documented 5 individuals of M. birostris that were landed by fishermen 
off the coast of Vizhinjam, Kovalam and Colachel over the course of 
only 7 days. On the east coast of India, Raje et al. (2007) documented 
43 mt of M. birostris landed in 2003 and 2004 at the Chennai fishing 
harbor. The apparent increase in landings since the sporadic reports of 
the species in the mid-1990s is likely due to the demand for the 
species' gill rakers, with M. birostris gill plates characterized as 
``First Grade'' and fetching the highest price at auction at the major 
fishing port of Cochin Fisheries Harbour (Nair et al. 2013).
    While Manta spp. are rarely reported in the catch from the western 
Pacific, with Hall and Roman (2013) noting that M. japonica represents 
the most abundant mobulid in the fisheries data, the available 
information still suggests the potential for bycatch mortality and 
indicates declining trends within this region. For example, based on 
observer data from the Western and Central Pacific Fisheries Commission 
(WCPFC) fisheries, M. birostris is observed at a rate of 0.0017 
individuals per associated set and 0.0076 individuals per unassociated 
set in the purse seine fisheries, and at a rate of 0.001-0.003 
individuals per 1,000 hooks in the longline fisheries (Tremblay-Boyer 
and Brouwer 2016). The longline standardized catch-per-unit-effort 
data, while covering observations from only the past decade, indicates 
that M. birostris is observed less frequently in recent years compared 
to 2000-2005 (Tremblay-Boyer and Brouwer 2016). Additionally, a sharp 
decline in the catches of manta rays off Papua New Guinea, where WCPFC 
fishing effort is high, was observed in Papua New Guinea purse seiner 
bycatch in 2005-2006, after a previously steady rise in manta ray 
catches from 1994-2005 (C. Rose pers. comm. cited in Marshall et al. 
2011b).
    In the eastern Pacific, giant manta rays are frequently reported as 
bycatch in the purse seine fisheries; however, identification to 
species level is difficult, and, as such, most manta and mobula ray 
captures are pooled together (Hall and Roman 2013). Based on reported 
M. birostris catch to the Inter-American Tropical Tuna Commission 
(IATTC), including available national observer program data, an average 
of 135 giant manta rays were estimated caught per year from 1993-2015 
in the eastern Pacific purse seine fishery by IATTC vessels (Hall 
unpublished data). While the impact of these bycatch levels on giant 
manta ray populations is uncertain, effort in the fishery appears to 
coincide with high productivity areas, such as the Costa Rica Thermal 
Dome, west of the Galapagos, off the Guayas River estuary (Ecuador), 
and off central and northern Peru, where giant mantas are likely to 
aggregate and have been observed caught in sets (Hall and Roman 2013). 
If effort is concentrated in manta ray aggregation areas, this could 
lead to substantial declines and potential local extirpations of giant 
manta ray populations. Already, evidence of declines in this portion of 
the giant manta ray's range is apparent, with White et al. (2015) 
estimating an 89 percent decline in the relative abundance of M. 
birostris off Cocos Island, Costa Rica. Presently, the largest 
population of M. birostris is thought to reside within the waters of 
the Machalilla National Park and the Galapagos Marine Reserve (Hearn et 
al. 2014); however, given the distribution of purse seine fishing 
effort, and the migratory nature of the species, it is likely that 
individuals from this population are highly susceptible to the purse 
seine fisheries operating in the area.
    Overall, given that the majority of observed declines in landings 
and sightings of manta rays originate from the Indo-Pacific and eastern 
Pacific portions of their range (see Table 5 in Miller and Klimovich 
2016), additional pressure on these species through bycatch mortality 
may have significant negative effects on local populations throughout 
this area. This is particularly a risk for M. birostris, which appears 
to be the species most frequently observed in the fisheries catch and 
bycatch, with this pressure already contributing to declines in the 
species (of up to 95 percent) throughout many areas (i.e., Indonesia, 
Philippines, Sri Lanka, Thailand, Madagascar, Costa Rica). As such, we 
find that current fisheries-related mortality rates are a threat 
significantly contributing to the overutilization of M. birostris 
throughout this portion of its range. Additionally, given the high 
market prices for manta ray gill plates, we find that the practice of 
landing these species as valuable bycatch will likely continue through 
the foreseeable future.

Disease or Predation

    No information has been found to indicate that disease or predation 
is a factor that is significantly and negatively affecting the status 
of manta rays. Manta rays are frequently observed congregating in 
inshore cleaning stations, often associated with coral reefs, where 
small cleaner fish remove parasites and dead tissue from their bodies 
(Marshall and Bennett 2010a; O'Shea et al. 2010; CITES 2013). They may 
remain at these cleaning stations for large periods of time, sometimes 
up to 8 hours a day, and may visit daily (Duinkerken 2010; Kitchen-
Wheeler 2013; Rohner et al. 2013). While there is no information on 
manta ray diseases, or data to indicate that disease is contributing to 
population declines in either species, impacts to these cleaning 
stations (such as potential loss through habitat degradation) may 
negatively impact the fitness of the mantas by decreasing their ability 
to reduce their parasite load. However, at this time, the impact and 
potential loss of cleaning stations is highly speculative.
    In terms of predation, manta rays are frequently sighted with non-
fatal injuries consistent with shark attacks, although the prevalence 
of these sightings varies by location (Homma et al. 1999; Ebert 2003; 
Mourier 2012). For example, Deakos et al. (2011) reported that scars 
from shark predation, mostly on the posterior part of the body or the 
wing tip, were evident in 24 percent of M. alfredi individuals observed 
at a manta ray aggregation site off Maui, Hawaii. At Lady Elliott 
Island, off eastern Australia, Couturier et al. (2014) observed 23 
percent of individuals had shark scars. In contrast, in southern 
Mozambique, between 2003 and 2006, 76.3 percent of the M. alfredi 
identified by Marshall and Bennett (2010a) exhibited shark-inflicted 
bite marks, the majority of which were already healed. Rohner et al. 
(2013) found a lower rate for M. birostris, with only 35 percent of 
individuals observed with bite marks. Marshall and Bennett (2010a) also 
recorded two mid-pregnancy abortions by pregnant female M. alfredi 
attributed to damage from shark attacks. The authors observed that the 
rate of shark-inflicted bites in southern Mozambique appears to be 
higher than predation rates in other manta ray populations, which is 
generally noted at less than five percent (Ito 2000; Kitchen-Wheeler et 
al. 2012), but it is unknown why this difference exists.
    Because the damage from a shark bite usually occurs in the 
posterior region of the manta ray, there may be disfigurement leading 
to difficult clasper insertion during mating or inhibited waste 
excretion (Clark and Papastamatiou 2008). Given the already low 
reproductive ability of these species, attacks by sharks (or 
occasionally killer whales, see Fertl et

[[Page 3705]]

al. (1996) and Visser and Bonoccorso (2003)) may pose a threat to the 
species by further impairing the manta rays' ability to rebuild after 
depletion. However, at this time, the impact of shark bites on manta 
ray reproduction, or predation mortality rates on the status of either 
species, is highly speculative.

The Inadequacy of Existing Regulatory Mechanisms

    Protections for manta rays are increasing, yet there are still a 
number of areas where manta rays are targeted or allowed to be landed 
as bycatch. In fact, only one of the Regional Fishery Management 
Organizations (RFMOs) has prohibited retention of bycaught manta rays. 
Additionally, because both manta species were identified as M. 
birostris prior to 2009, some national protections that were 
implemented before 2009 are specific only to giant manta rays, despite 
both species being present in that nation's waters. Below we provide an 
analysis of the adequacy of measures in terms of controlling threats to 
each species where available data permit. A list of current protections 
for manta rays can be found in the Appendix of Miller and Klimovich 
(2016).
Overutilization of M. birostris
    Based on the available data, M. birostris appears to be most at 
risk of overutilization in the Indo-Pacific and eastern Pacific 
portions of its range. Targeted fishing and incidental capture of the 
species in Indonesia, Philippines, Sri Lanka, and India, and throughout 
the eastern Pacific, has led to observed declines in the M. birostris 
populations. Despite national protections for the species, poor 
enforcement and illegal fishing have essentially rendered the existing 
regulatory mechanisms inadequate to achieve their purpose of protecting 
the giant manta ray from fishing mortality.
    In Indonesia, M. birostris and M. alfredi were provided full 
protection in the nation's waters in 2014 (4/KEPMEN-KP/2014), with the 
creation of the world's largest manta ray sanctuary at around 6 million 
km\2\. Fishing for the species and trade in manta ray parts are banned. 
Despite this prohibition, fishing for manta rays continues, with 
evidence of the species being landed and traded in Indonesian markets 
(AFP 2014; Marshall and Conradie 2014; Dharmadi et al. 2015). As 
mentioned previously (see Overutilization for commercial, recreational, 
scientific, or educational purposes), many fishermen throughout 
Indonesia rely on shark and ray fishing for their livelihoods, and 
without an alternative source of income, are unlikely to stop their 
traditional fishing practices, including the targeting of manta rays. 
Additionally, in interviews with fishermen, many viewed the prohibition 
positively because it would likely drive up the market price of manta 
ray products (Marshall and Conradie 2014). Given the size of the 
Indonesian archipelago, and current resources, Dharmadi et al. (2015) 
note there are many issues with current enforcement of regulations. For 
example, the collection of data is difficult due to insufficient 
fisheries officers trained in species identification and the large 
number of landing sites that need to be monitored (over 1,000). Catch 
data are typically not accurately recorded at the smaller landing sites 
either, with coastal waters heavily fished by artisanal fishermen using 
non-selective gear (Dharmadi et al. 2015). Given the issues with 
enforcement and evidence of illegal fishing, existing regulatory 
mechanisms are inadequate to protect the species from further declines 
due to overutilization.
    In the Philippines, legal protection for manta rays was introduced 
in 1998; however, similar to the situation in Indonesia, enforcement of 
the prohibitions is lacking and illegal fishing of the species is 
evident. For example, in a random sampling of 11 dried products of 
sharks and rays confiscated for illegal trading, Asis et al. (2016) 
found that four of the products could be genetically identified as 
belonging to M. birostris. Dried manta meat and gill rakers were 
frequently observed in markets between 2010 and 2012, and fishing boats 
specifically targeting mobulids (including manta rays) were identified 
in a number of local fishing villages in the Philippines, with landings 
consisting of M. birostris individuals. Fishing for mobulids is a ``way 
of life'' and the primary source of income for many fishermen, and with 
the high prices for manta gill rakers in the Philippine markets (where 
an average manta ray of around 3 m DW could fetch up to $808; Acebes 
and Tull (2016)), it is unlikely that pressure on the species will 
decrease. With essentially no efforts to regulate the mobulid fisheries 
in the Philippines, and a severe lack of enforcement of the current 
manta ray hunting prohibition, current regulations to protect M. 
birostris from overutilization in the Philippines are inadequate.
    In the eastern and central Indian Ocean, very few national 
protections have been implemented for M. birostris. Essentially, 
fishing for the species and retention of bycatch is allowed except 
within the Republic of Maldives EEZ and within specific marine parks of 
Western Australia. Given the declines observed in the species 
throughout the Indian Ocean, and the migratory nature of the animal, 
with the potential for the species to move out of protected areas into 
active fishing zones (e.g., from the Maldives to Sri Lanka--a distance 
of ~820 km, well within the ability of M. birostris), it is likely that 
existing regulatory measures within this portion of the species' range 
are inadequate to protect it from overutilization.
    In the eastern Pacific portion of the species' range, the IATTC 
recently implemented a prohibition on the retention, transshipment, 
storage, landing, and sale of all devil and manta (mobula and manta) 
rays taken in its large-scale fisheries (Resolution C-15-04). This 
regulation went into force on August 1, 2016. Cooperating members must 
report mobulid catch data and ensure safe release; however, developing 
countries were granted an exception for small-scale and artisanal 
fisheries that catch these species for domestic consumption. Given that 
M. birostris is primarily caught as bycatch in the IATTC purse seine 
fisheries, the adequacy of this prohibition in protecting the species 
from overutilization depends on the post-release survival rate of the 
species. While injuries from entanglements in fishing gear (e.g., 
gillnets and longlines) have been noted (Heinrichs et al. 2011), at 
this time, at-vessel and post-release mortality rates for manta rays in 
purse seine nets are unknown. For other Mobula species, Francis and 
Jones (2016) provided preliminary evidence that may indicate a 
potential for significant post-release mortality of the spinetail 
devilray (Mobula japanica) in purse seine fisheries; however, the study 
was based on only seven observed individuals and, because of this, the 
authors caution that it is ``premature to draw conclusions about 
survival rates.'' In fact, based on observer data in the New Zealand 
purse seine fishery, mentioned in Francis and Jones (2016), rays that 
were caught during sets and released were ``usually lively'' and swam 
away from the vessel and judged by the observers as ``likely to 
survive.'' Although decreasing purse seine fishing effort in manta ray 
hotspots would significantly decrease the likelihood of bycatch 
mortality, without further information on post-release survival rates, 
it is highly uncertain if the prohibition will be adequate in 
decreasing the mortality of the species.
    Additionally, in 2016, prohibitions on the fishing and sale of M. 
birostris and requirement for immediate release of mantas caught as 
bycatch were

[[Page 3706]]

implemented in Peru. Ecuador banned the fishing, landing and sale of 
manta rays in its waters back in 2010. Given that the largest 
population of M. birostris is found in the waters between Peru and 
Ecuador (with the Isla de la Plata population estimated at around 1,500 
individuals), these prohibitions should provide some protection to the 
species from fishing mortality when in these waters. However, illegal 
fishing still occurs in these waters. For example, in Ecuador's 
Machalilla National Park (a major M. birostris aggregation site), 
researchers have observed large numbers of manta rays with life-
threatening injuries as a result of incidental capture in illegal wahoo 
(Acanthocybium solandri) trawl and drift gillnet fisheries operating 
within the park (Heinrichs et al. 2011; Marshall et al. 2011a). 
Depending on the extent of the activities, illegal fishing could 
potentially contribute to local declines in the population if not 
adequately controlled. Also, given the migratory nature of the species, 
national protections may not be adequate to protect the species from 
overutilization throughout its range, particularly when the species 
crosses boundary lines where protections no longer exist, as evidenced 
by the significant decline in M. birostris observed in Cocos Island 
National Park, Costa Rica (White et al. 2015).
Overutilization of M. alfredi
    Despite a significant overlap in range with M. birostris in the 
Indian and Pacific Oceans, and the more nearshore and reef-associated 
resident behavior, M. alfredi is rarely identified in commercial and 
artisanal fisheries catch. While the prior lumping of all manta rays as 
M. birostris may account for these findings, in certain portions of the 
species' range, the distribution of M. alfredi may not overlap with the 
areas of fishing operations. For example, in the Philippines, 
Rambahiniarison et al. (2016) explains that capture of reef manta rays 
is unusual, as the main mobulid fishing ground in the Bohol Sea lies 
offshore in deeper waters, where the presence of the more coastal M. 
alfredi is unlikely. Additionally, while M. alfredi are known to make 
night time deep-water dives offshore for foraging (>150 m; Braun et al. 
(2014)), the driftnets deployed by the mobulid fishermen are set at 
night at much shallower maximum depths of 40 m and thus are unlikely to 
catch the species (Rambahiniarison et al. 2016). However, Acebes and 
Tull (2016) did observe a new, active mobulid fishery off Dinagat 
Island in northern Mindanao that appears to target M. alfredi around 
seamounts in the Leyte Gulf. In 2010, there were 4 active fishing boats 
in this fishery, supplying manta ray products to Bohol during the ``off 
season'' (Acebes and Tull 2016). While it is uncertain whether fishing 
pressure on M. alfredi will increase in the future (given that the 
majority of effort is presently concentrated outside of their 
distribution), current regulations in the Philippines only prohibit 
fishing of M. birostris, and, as such, are inadequate to protect the 
species from potential declines in the future.
    In Indonesia, while the majority of landings data is reported as M. 
birostris, anecdotal reports from fishermen note that M. alfredi used 
to be caught as bycatch in drift gillnets. Evidence of declines and 
extirpations of local reef manta ray populations suggest that the 
species is at risk of overutilization by fisheries in these local, 
inshore areas, despite a lack of records. As such, the inadequacy of 
existing mechanisms (discussed previously) may pose a threat to the 
remaining local reef manta ray populations in Indonesia.
    In the Indian Ocean, M. alfredi is subject to targeted fishing in 
the western Indian Ocean (off Mozambique) where declines of up to 88 
percent have been observed but no fishery protections or regulatory 
measures are in place. While the Commonwealth of Australia has now 
listed both species of Manta on its list of migratory species under its 
Environment Protection and Biodiversity Conservation Act 1999, which 
means that any action that may have a significant impact on the species 
must undergo an environmental assessment and approval process, there 
are no specific regulatory protections for the species throughout 
Western Australian waters. Manta spp. are only explicitly protected 
from targeted fishing within Ningaloo Marine Park and, collectively, 
with all species in small designated zones along the Western Australian 
coast; however, it is important to note that neither species is subject 
to directed fishing in these waters. In fact, in those portions of the 
species' range where populations are either not fished and/or are 
afforded protection and appear stable, we find existing regulatory 
measures to be adequate in protecting the species from overutilization. 
These areas include waters of Australia, Hawaii, Guam, Japan, the 
Republic of Maldives, Palau, and Yap. Given the more coastal and 
resident behavior of M. alfredi, national measures prohibiting fishing 
of manta rays are likely to provide adequate protection to the species 
from overutilization through the foreseeable future.
Tourism Impacts
    Codes of conduct have been developed by a number of organizations 
and used by dive operators to promote the safe viewing of manta rays 
and reduce the potential negative impacts of these activities on manta 
rays (see Other Natural or Man-Made Factors Affecting Its Continued 
Existence for discussion of this threat). The Manta Trust, a UK-
registered charity, has developed a number of guidelines for divers, 
snorkelers, tour group operators, and in-water tourists, based on 
studies of interaction effects conducted by the organization from 2005-
2013 (available here: https://www.mantatrust.org/awareness/resources/). 
The Hawaii Association for Marine Education and Research Inc. (2014) 
notes that codes of conduct for manta ray dive operators have been 
implemented in a number of popular manta ray diving locales, including 
Kona, Hawaii, Western Australia, Mozambique, Bora Bora, and in the 
Maldives; however, information on the adherence to, effectiveness, or 
adequacy of these codes of conduct in minimizing potential negative 
impacts of tourism activities on the populations could not be found.

Other Natural or Man-Made Factors Affecting Its Continued Existence

    Manta rays are known to aggregate in various locations around the 
world, in groups usually ranging from 100-1,000 for M. birostris and 
100-700 for M. alfredi (Notarbartolo-di-Sciara and Hillyer 1989; Graham 
et al. 2012; Venables 2013). These sites function as feeding sites, 
cleaning stations, or sites where courtship interactions take place 
(Heinrichs et al. 2011; Graham et al. 2012; Venables 2013), with the 
appearance of manta rays at these locations generally predictable and 
related to food availability (Notarbartolo-di-Sciara and Hillyer 1989; 
Heinrichs et al. 2011; Jaine et al. 2012). Additionally, manta rays 
exhibit learned behaviors, with diving spots using artificial lights to 
concentrate plankton and attract manta rays (Clark 2010). These 
behavioral traits, including the predictable nature of manta ray 
appearances, combined with their slow swimming speeds, large size, and 
lack of fear towards humans, may increase their vulnerability to other 
threats, such as overfishing, which was previously discussed, and 
tourism (O'Malley et al. 2013; CMS 2014).
    Tourism was identified as a potential threat to the species, given 
that interacting (i.e., swimming) with manta rays is a significant 
tourist attraction throughout the range of both species. In

[[Page 3707]]

fact, O'Malley et al. (2013) estimated that the manta ray tourism 
industry provides $140 million annually in direct revenue or economic 
impact. Regular manta ray concentrations off Mozambique, parts of 
Indonesia, Australia, Philippines, Yap, southern Japan, Hawaii, and 
Mexico have all become tourist attractions where manta dives are common 
(Anderson et al. 2011b). Estimates of the number of people interacting 
with manta rays per year at these popular dive sites are significant, 
ranging from over 10,000 at Ho'ona Bay (Hawaii; Clark (2010)) to at 
least 14,000 in the Maldives (Anderson et al. 2011b).
    While manta ray tourism is far less damaging to the species than 
the impact of fisheries, this increasing demand to see and dive with 
the animals has the potential to lead to other unintended consequences 
that could harm the species. For example, Osada (2010) found that a 
popular manta dive spot in Kona, Hawaii, had fewer emergent zooplankton 
and less diversity compared to a less used dive spot, and attributed 
the difference to potential inadvertent habitat destruction by divers. 
Tour groups may also be engaging in inappropriate behavior, such as 
touching the mantas. Given the increasing demand for manta ray tourism, 
with instances of more than 10 tourism boats present at popular dive 
sites with over 100 divers in the water at once (Anderson et al. 2011b; 
Venables 2013), without proper tourism protocols, these activities 
could have serious consequences for manta ray populations.
    Already, evidence of tourism activities potentially altering manta 
ray behavior has been observed. For example, from 2007-2008, low 
numbers of mantas were observed at normally popular manta dive sites in 
the Maldives while manta ray numbers remained stable at less visited 
sites (Anderson et al. 2011b). Similarly, De Rosemont (2008) noted the 
disappearance of a resident manta ray colony from a popular cleaning 
station in a Bora Bora lagoon in 2005, and attributed the absence to 
new hotel construction and increased tourism activities; however, by 
2007, the author notes that the mantas had returned to the site. In a 
study of the tourism impacts on M. alfredi behavior in Coral Bay, 
Western Australia, Venables (2013) observed that mantas exhibited a 
variety of behavioral changes in response to swim group interactions 
(i.e., their response was different than their behavior prior to the 
approach of the swim group). Although the long-term effects of tourism 
interactions are at this time unknown, the results from the Venables 
(2013) study provide a preliminary estimate of the potentially minimum 
response of the species to interactions with tourists, and indicates 
that these interactions can cause the species to alter (and even stop) 
behaviors that serve critical biological functions (such as feeding and 
cleaning). Additional studies on both the short-term and long-term 
impact of tourist interactions with manta rays are needed in order to 
evaluate if this interaction is a potential threat to the survival of 
the species.
    In addition to tourism activities, another potential threat to both 
manta ray species is an increase in mortality from boat strikes and 
entanglements. Because manta ray aggregation sites are sometimes in 
areas of high maritime traffic (such as Port Santos in Brazil or in the 
Caribbean (Marshall et al. 2011a; Graham et al. 2012)), manta rays are 
at potential risk of being struck and killed by boats. Mooring and boat 
anchor line entanglement may also wound manta rays or cause them to 
drown (Deakos et al. 2011; Heinrichs et al. 2011). For example, in a 
Maui, Hawaii, M. alfredi population (n = 290 individuals), Deakos et 
al. (2011) observed that 1 out of 10 reef manta rays had an amputated 
or disfigured non-functioning cephalic fin, likely a result of line 
entanglement. Internet searches also reveal photographs of mantas with 
injuries consistent with boat strikes and line entanglements, and manta 
researchers report that such injuries may affect manta fitness in a 
significant way (The Hawaii Association for Marine Education and 
Research Inc. 2005; Deakos et al. 2011; Heinrichs et al. 2011; 
Couturier et al. 2012; CMS 2014; Germanov and Marshall 2014; Braun et 
al. 2015), potentially similar to the impacts of shark or orca attacks. 
However, there is very little quantitative information on the frequency 
of these occurrences and no information on the impact of these injuries 
on the overall health of the populations.

Assessment of Extinction Risk

    The ESA (section 3) defines an endangered species as ``any species 
which is in danger of extinction throughout all or a significant 
portion of its range.'' A threatened species is defined as ``any 
species which is likely to become an endangered species within the 
foreseeable future throughout all or a significant portion of its 
range.'' For the term ``foreseeable future,'' we define it as the time 
frame over which identified threats could be reliably predicted to 
impact the biological status of the species. For the assessment of 
extinction risk for both manta ray species, the ``foreseeable future'' 
was considered to extend out several decades (>50 years). Given both 
species' life history traits, with longevity estimated to be greater 
than 20-40 years, maturity ranges from 3 to >15 years, reproductive 
periodicity anywhere from an annual cycle to a 5-year cycle, with a 
litter of only 1 pup, and a generation time estimated to be around 25 
years, it would likely take more than a few decades (i.e., multiple 
generations) for any recent management actions to be realized and 
reflected in population abundance indices. Similarly, the impact of 
present threats to both species could be realized in the form of 
noticeable population declines within this time frame, as demonstrated 
in the very limited available sightings time-series data. As the main 
potential operative threat to the species is overutilization by 
commercial and artisanal fisheries, this time frame would allow for 
reliable predictions regarding the impact of current levels of fishery-
related mortality on the biological status of the two species. 
Additionally, this time frame allows for consideration of the 
previously discussed impacts on manta ray habitat from climate change 
and the potential effects on the status of these two species.
    In determining the extinction risk of a species, it is important to 
consider both the demographic risks facing the species as well as 
current and potential threats that may affect the species' status. To 
this end, a demographic analysis was conducted for the giant manta ray 
and the reef manta ray. A demographic risk analysis is an assessment of 
the manifestation of past threats that have contributed to the species' 
current status and informs the consideration of the biological response 
of the species to present and future threats. This analysis evaluated 
the population viability characteristics and trends available for the 
manta rays, such as abundance, growth rate/productivity, spatial 
structure and connectivity, and diversity, to determine the potential 
risks these demographic factors pose to each species. The information 
from this demographic risk analysis was considered alongside the 
information previously presented on threats to these species, including 
those related to the factors specified by the ESA section 4(a)(1)(A)-
(E) (and summarized in a separate Threats Assessment section below) and 
used to determine an overall risk of extinction for M. birostris and M. 
alfredi. Because species-specific information is sporadic and sometimes

[[Page 3708]]

uncertain (due to the prior lumping of the Manta genus), the 
qualitative reference levels of ``low risk,'' ``moderate risk'' and 
``high risk'' were used to describe the overall assessment of 
extinction risk, with detailed definitions of these risk levels found 
in the status review report (Miller and Klimovich 2016).

Demographic Risk Analysis

Giant Manta Ray

Abundance
    Current and accurate abundance estimates are unavailable for the 
giant manta ray, as the species tends to be only sporadically observed. 
While observations of individuals in local aggregations range from 
around 40 individuals to over 600, estimates of subpopulation size have 
only been calculated for Mozambique (n = 600 individuals) and Isla de 
la Plata, Ecuador (n = 1,500 individuals).
    If a population is critically small in size, chance variations in 
the annual number of births and deaths can put the population at added 
risk of extinction. Demographic stochasticity refers to the variability 
of annual population change arising from random birth and death events 
at the individual level. When populations are very small, chance 
demographic events can have a large impact on the population. The 
conservation biology ``50/500'' rule-of-thumb suggests that the 
effective population size (Ne; the number of reproducing individuals in 
a population) in the short term should not be <50 individuals in order 
to avoid inbreeding depression and demographic stochasticity (Franklin 
1980; Harmon and Braude 2010). In the long-term, Ne should not be <500 
in order to decrease the impact of genetic drift and potential loss of 
genetic variation that will prevent the population from adapting to 
environmental changes (Franklin 1980; Harmon and Braude 2010). Given 
the two available subpopulation estimates, M. birostris is not likely 
to experience extreme fluctuations that could lead to depensation; 
however, data are severely lacking. The threshold for depensation in 
giant manta rays is also unknown. Additionally, the genetic diversity 
in the giant manta ray has not been investigated. While a preliminary 
study suggests that the species may exist as isolated subpopulations, 
available tracking information indicates these manta rays are pelagic 
and migratory and can likely travel large distances to reproduce. It is 
this more transient and pelagic nature of the species that has made it 
difficult to estimate population sizes.
    Yet, given the reports of anecdotal declines in sightings and 
decreases in M. birostris landings (of up to 95 percent) in areas 
subject to fishing (particularly the Indo-Pacific and eastern Pacific 
portions of the species' range), with take estimates that currently 
exceed those subpopulation and aggregation estimates (e.g., 50-3,125 
individuals), abundance of these particular populations may be at 
levels that place them at increased risk of genetic drift and 
potentially at more immediate risks of inbreeding depression and 
demographic stochasticity. Extirpations of these populations would 
inherently increase the overall risk of extinction for the entire 
species.
Growth Rate/Productivity
    The current net productivity of M. birostris is unknown due to the 
imprecision or lack of available abundance estimates or indices. 
Fecundity, however, is extremely low, with one pup per litter and a 
reproductive periodicity of 1-2 years. Using estimates of life history 
parameters for both giant and reef manta rays, Dulvy et al. (2014) 
calculated a median maximum population growth rate to be 0.116 (one of 
the lowest values compared to other shark and ray species), and 
estimated productivity (r) to be 0.029. Ward-Paige et al. (2013) 
calculated a slightly higher intrinsic rate of population increase for 
M. birostris at r = 0.042; however, both these estimates indicate that 
the giant manta ray has very low productivity and, thus, is extremely 
susceptible to decreases in its abundance.
    Given their large sizes, manta rays are assumed to have a fairly 
high survival rate after maturity (e.g., low natural predation), with 
estimated annual survival rates for M. alfredi populations supporting 
this assumption. Based on modeling work on M. alfredi, adult survival 
rate was found to be the most significant factor affecting the 
viability of the population.
    Additionally, at this time, no changes in demographic or 
reproductive traits or barriers to the exploitation of requisite 
habitats/niches/etc. have been observed in M. birostris.
Spatial Structure/Connectivity
    The giant manta ray inhabits tropical, subtropical, and temperate 
bodies of water and is commonly found offshore, in oceanic waters, and 
near productive coastlines. It occurs over a broad geographic range and 
is found in all ocean basins. Most tagging and tracking studies 
indicate that the home range of individuals is likely large, with the 
species exhibiting migratory behavior and distances tracked of up to 
1,500 km. However, a recent study of the M. birostris population found 
off Pacific Mexico suggests there may be a degree of spatial 
structuring within the species. At this time, it is unknown whether 
natural rates of dispersal among populations are too low to prevent 
sufficient gene flow among populations. Additionally, there is no 
information to indicate that M. birostris is composed of conspicuous 
source[hyphen]sink populations or habitat patches.
Diversity
    Rates of dispersal and gene flow are not known to have been altered 
in M. birostris. Presently, giant manta rays are wide[hyphen]ranging 
inhabitants of offshore, oceanic waters and productive coastline 
ecosystems and thus are continually exposed to ecological variation at 
a broad range of spatial and temporal scales. As such, large-scale 
impacts that affect ocean temperatures, currents, and potentially food 
chain dynamics, may pose a threat to this species. However, given the 
migratory behavior of the giant manta ray and tolerance to both 
tropical and temperate waters, these animals likely have the ability to 
shift their range or distribution to remain in an environment conducive 
to their physiological and ecological needs, providing the species with 
resilience to these effects. At this time, there is no information to 
suggest that natural processes that cause ecological variation have 
been significantly altered to the point where M. birostris is at risk.

Reef Manta Ray

Abundance
    Current and accurate abundance estimates are unavailable for the 
reef manta ray. Observations of individuals in local aggregations range 
from 35 individuals to over 2,400; however, many are on the order of 
100-600 individuals. Subpopulation sizes range from 100 to 350 
individuals, with the exception of the Maldives at 3,300-9,677 
individuals. Meta-population estimates for southern Mozambique and 
Ningaloo Reef, Australia are 802-890 and 1,200-1,500 individuals, 
respectively.
    The rather low subpopulation estimates for M. alfredi throughout 
most of its range suggest that the species may be at increased risk of 
genetic drift and potential loss of genetic variation. Unlike the giant 
manta ray, M. alfredi is thought to be a more resident species, with 
populations that occur year-round at certain sites. This reproductive 
isolation further increases the risk of

[[Page 3709]]

inbreeding depression and potential inability of the population to 
respond to environmental variation or anthropogenic perturbations. For 
example, Kashiwagi (2014) recently estimated the effective population 
size of the M. alfredi population off the Yaeyama Islands to be Ne = 
89, indicating that the population is not part of a large gene pool and 
may be close to a level where viability could be jeopardized in the 
shorter term. Total population was estimated at 165-202 individuals, 
indicating long-term viability vulnerability. With most available 
subpopulation estimates ranging only from 100 to 600 individuals (with 
the exception of Western Australia, Maldives, and Southern Mozambique), 
it is likely that these populations similarly have low effective 
population sizes that may increase their vulnerability to inbreeding 
depression, the loss of genetic variants, or fixation of deleterious 
mutations.
    Overall, based on the information above, the estimates of small and 
isolated subpopulations throughout most of the species' range, with the 
three exceptions off Mozambique, Maldives, and Western Australia, 
inherently place M. alfredi at an increased risk of extinction from 
environmental variation or anthropogenic perturbations. However, the 
trend in overall abundance of M. alfredi is highly uncertain.
Growth Rate/Productivity
    The current net productivity of M. alfredi is unknown due to the 
imprecision or lack of available abundance estimates or indices. 
Fecundity, however, is extremely low, with one to, rarely, two pups per 
litter and a reproductive periodicity of anywhere from 1-5 years. 
Estimated productivity (r) values range from 0.023 to 0.05, indicating 
that the reef manta ray has very low productivity and, thus, is 
extremely susceptible to decreases in its abundance.
    Annual survival rate for reef manta rays is fairly high. Estimated 
survival rates for subpopulations range from 0.95 to 1 off Australia, 
Hawaii, and Japan (Deakos et al. 2011; Couturier et al. 2014; Kashiwagi 
2014). In Mozambique, rates were lower, between 0.6-0.7; however shark 
attacks are also more common in this area (Marshall et al. 2011c). 
Based on modeling work, Smallegange et al. (2016) showed that 
population growth rate was most sensitive to changes in the survival of 
adults.
    Additionally, no changes in demographic or reproductive traits or 
barriers to the exploitation of requisite habitats/niches/etc. have 
been observed.
Spatial Structure/Connectivity
    The reef manta ray is commonly seen inshore near coral and rocky 
reefs. The species is associated with warmer waters (>21 [deg]C) and 
productive nearshore habitats (such as island groups). It is considered 
a more resident species than M. birostris. While the species has been 
tracked undertaking long-distance movements (>700 km), usually to 
exploit offshore productive areas, reef manta rays tend to return to 
known aggregation sites, indicating a degree of site-fidelity. Based on 
photo-identification surveys of the M. alfredi population off Maui, 
Hawaii, Deakos et al. (2011) suggested that geographic barriers, such 
as deep channels, might be barriers to movement between neighboring M. 
alfredi populations. Collectively, this information suggests that gene 
flow is likely limited among populations of M. alfredi, particularly 
those separated by deep ocean expanses.
    With the exception of the Yaeyama, Japan population of M. alfredi, 
which Kashiwagi (2014) hypothesized may be a ``sink'' population but is 
presently increasing with a population growth rate of 1.02-1.03, there 
is no information to indicate that M. alfredi is composed of 
conspicuous source[hyphen]sink populations or habitat patches whose 
loss may pose a risk of extinction.
Diversity
    Given their tendency towards site fidelity, M. alfredi likely 
exists as isolated populations with low rates of dispersal and little 
gene flow among populations. Currently, there is no information to 
suggest that natural processes that cause ecological variation have 
been significantly altered to the point where the species is at risk. 
Reef manta rays also likely have the ability to shift their 
distribution to remain in an environment conducive to their 
physiological and ecological needs, providing the species with 
resilience to these effects. For example, in response to changing 
ecological conditions, like the biannual reversal of monsoon currents, 
reef manta rays will migrate to the downstream side of atolls, 
potentially to remain in nutrient-rich waters year-round (Anderson et 
al. 2011a). Presently, there is no information to suggest that natural 
processes that cause ecological variation have been significantly 
altered to the point where M. alfredi is at risk.

Threats Assessment

Giant Manta Ray

    The most significant and certain threat to the giant manta ray is 
overutilization for commercial purposes. Giant manta rays are both 
targeted and caught as bycatch in a number of global fisheries 
throughout their range. Estimated take of giant manta rays, 
particularly in many portions of the Indo-Pacific, frequently exceeds 
numbers of observed individuals in those areas, and is accompanied by 
observed declines in sightings and landings of the species. Efforts to 
address overutilization of the species through regulatory measures 
appear inadequate, with evidence of targeted fishing of the species 
despite prohibitions (Indo-Pacific; Eastern Pacific) and only one 
regional measure to address bycatch issues, with uncertain 
effectiveness (Eastern Pacific). Additionally, given the migratory and 
pelagic behavior, national protections for the species are less likely 
to adequately protect the species from fisheries-related mortality. 
Giant manta rays are not confined by national boundaries and may, for 
example, lose certain protections as they conduct seasonal migrations 
or even as they move around to feed if they cross particular national 
jurisdictional boundaries (e.g., between the Maldives and Sri Lanka or 
India), move outside of established Marine Protected Areas, or enter 
into high seas. While the species recently has been added to CITES 
Appendix II (added in March 2013 with a delayed effectiveness of 
September 2014), which may curb targeted fishing as countries must 
ensure that manta ray products are legally obtained and trade is 
sustainable, the species is still likely to be caught as bycatch in the 
industrial fisheries and targeted by artisanal fisheries for domestic 
consumption.
    Other threats to M. birostris that potentially contribute to long-
term risk of the species include (micro) plastic ingestion rates, 
increased parasitic loads as a result of climate change effects, and 
potential disruption of important life history functions as a result of 
increased tourism; however, due to the significant data gaps, the 
likelihood and impact of these threats on the status of the species is 
highly uncertain.

Reef Manta Ray

    Given their more inshore distribution and association with shallow 
coral and rocky reefs, M. alfredi does not appear to be as vulnerable 
to commercial and larger-scale artisanal fishing operations as M. 
birostris. These fisheries tend to operate in deeper and more pelagic

[[Page 3710]]

waters, targeting migratory and commercially valuable species (like 
tunas, billfishes, and sharks), and, hence, have a higher likelihood of 
catching giant manta rays. In the available information, only two 
countries are reported to have targeted artisanal fisheries for M. 
alfredi: The Philippines (documented 4 fishing boats) and Mozambique. 
The species has been identified in bycatch from Indonesia, Papua New 
Guinea, and Kiribati, with subsequent observed declines in sightings, 
and potential local extirpations; however, the extent of fishing 
mortality on the species throughout its range is highly uncertain. 
Additionally, the lumping of both species as M. birostris prior to 
2009, as well as the fact that much of the catch is not reported down 
to species level, also significantly contributes to this uncertainty. 
However, based on the data available, many of the identified 
populations of M. alfredi throughout the western and central Pacific 
are currently protected by regulations and appear stable, indicating 
that these existing regulatory measures are adequate at protecting the 
species from declines due to fishing mortality. Within the Indian 
Ocean, national protections exist for the large population of M. 
alfredi off the Maldives, and while specific protections for M. alfredi 
have not been implemented in Western Australia, the species is not 
subject to directed fishing (or prevalent in bycatch) and is presently 
one of the largest identified populations.
    Climate change was identified as a potential threat contributing to 
the long-term extinction risk of the species. Because M. alfredi are 
more commonly associated with coral reefs compared to giant manta rays, 
frequently aggregating within these habitats and showing a high degree 
of site-fidelity and residency to these areas, we found the impact of 
climate change on coral reefs to be a potential risk to the species. 
Although the species itself is not dependent on corals, which are most 
susceptible to the effects of climate change, the manta rays rely on 
the reef community structure, like the abundance of cleaner fish, to 
carry out important functions, such as removing parasite loads and dead 
tissue. Coral reef community structure is likely to be altered as a 
result of increasing events of coral bleaching through the foreseeable 
future; however, what this change will look like and its subsequent 
impact on the species is highly uncertain. Similarly, changes in 
zooplankton communities and distribution, including in and around coral 
reefs, are also likely to occur as a result of climate change, 
affecting the potential previous predictability of M. alfredi food 
resources. Reef manta rays may need to venture out farther to find 
available food or search for new productive areas; however, given that 
the species has been shown capable of making long-distance foraging 
movements, the impact of this potential displacement or change in 
distribution of zooplankton may not be a significant contributor to the 
species' extinction risk.
    Other threats that potentially contribute to long-term risk of the 
species include (micro) plastic ingestion rates, and potential 
disruption of important life history functions or destruction of 
habitat as a result of increased tourism; however, due to the 
significant data gaps, the likelihood and impact of these threats on 
the status of the species is highly uncertain.

Overall Risk Summary

Giant Manta Ray

    Given the extremely low reproductive output and overall 
productivity of the giant manta ray, it is inherently vulnerable to 
threats that would deplete its abundance, with a low likelihood of 
recovery. While there is considerable uncertainty regarding the current 
abundance of M. birostris throughout its range, the best available 
information indicates that the species has experienced population 
declines of potentially significant magnitude within areas of the Indo-
Pacific and eastern Pacific portions of its range, primarily due to 
fisheries-related mortality. Yet, larger subpopulations of the species 
still exist, including off Mozambique (where declines were not 
observed) and Ecuador. However, as giant manta rays are a migratory 
species and continue to face fishing pressure, particularly from the 
industrial purse seine fisheries and artisanal gillnet fisheries 
operating within the Indo-Pacific and eastern Pacific portions of its 
range, overutilization will continue to be a threat to these remaining 
M. birostris populations through the foreseeable future, placing them 
at a moderate risk of extinction.
    While we assume that declining populations within the Indo-Pacific 
and eastern Pacific portions of its range will likely translate to 
overall declines in the species throughout its entire range, there is 
very little information on the abundance, spatial structure, or extent 
of fishery-related mortality of the species within the Atlantic portion 
of its range. As such, we cannot conclude that the species is at a 
moderate risk of extinction throughout its entire range. However, under 
the final Significant Portion of Its Range (SPR) policy, we must 
consider whether the species may be in danger of extinction, or likely 
to become so within the foreseeable future, in a significant portion of 
its range (79 FR 37577; July 1, 2014).
Significant Portion of Its Range (SPR) Analysis
    To identify only those portions that warrant further consideration 
under the SPR Policy, we must determine whether there is substantial 
information indicating that (1) the portions may be significant and (2) 
the species may be in danger of extinction in those portions or likely 
to become so within the foreseeable future. With respect to the second 
of those determinations, as mentioned previously, the best available 
information indicates that the giant manta ray faces concentrated 
threats throughout the Indo-Pacific and eastern Pacific portion of its 
range. Estimated take of giant manta rays is frequently greater than 
the observed individuals in those areas, with observed declines in 
sightings and landings of the species of up to 95 percent. Efforts to 
address overutilization of the species through regulatory measures 
appear inadequate in this portion of its range, with evidence of 
targeted fishing of the species despite prohibitions and bycatch 
measures that may not significantly decrease fisheries-related 
mortality rates of the species. Based on the demographic risks and 
threats to the species in this portion, we determined that the species 
has a moderate risk of extinction in this portion of its range.
    Next, we must evaluate whether this portion is ``significant.'' As 
defined in the SPR Policy, a portion of a species' range is 
``significant'' ``if the species is not currently endangered or 
threatened throughout its range, but the portion's contribution to the 
viability of the species is so important that, without the members in 
that portion, the species would be in danger of extinction, or likely 
to become so in the foreseeable future, throughout all of its range'' 
(79 FR 37578; July 1, 2014). Without the Indo-Pacific and eastern 
Pacific portion of the species' range, the species would have to depend 
on only its members in the Atlantic for survival. While areas 
exhibiting source-sink dynamics, which could affect the survival of the 
species, are not known, the largest subpopulations and records of 
individuals of the species come from the Indo-Pacific and eastern 
Pacific portion. The only data from the Atlantic on the abundance of 
the species are records of >70 individuals in the Flower Garden

[[Page 3711]]

Banks Marine Sanctuary (Gulf of Mexico) and 60 manta rays from waters 
off Brazil (see Table 4 in Miller and Klimovich (2016)). Given that the 
species is rarely identified in the fisheries data in the Atlantic, it 
may be assumed that populations within the Atlantic are small and 
sparsely distributed. These demographic risks, in conjunction with the 
species' inherent vulnerability to depletion, indicate that even low 
levels of mortality may portend drastic declines in the population. As 
such, without the Indo-Pacific and eastern Pacific portion, the minimal 
targeted fishing of the species by artisanal fishermen and bycatch 
mortality from the purse seine, trawl, and longline fisheries operating 
in the Atlantic becomes a significant contributing factor to the 
extinction risk of the species. Based on the above findings, we 
conclude that the Indo-Pacific and eastern Pacific portion of the giant 
manta ray's range comprises a significant portion of the range of the 
species because this portion's contribution to the viability of M. 
birostris is so important that, without the members in this portion, 
the giant manta ray would likely become in danger of extinction within 
the foreseeable future, throughout all of its range.
    Under the SPR policy, we conclude that the Indo-Pacific and eastern 
Pacific portion of the giant manta ray's range qualifies as a 
significant portion of the species' range. Additionally, based on the 
information above and further discussed in our demographic risks 
analysis and threats assessment, as well as the information in the 
status review report, we conclude that M. birostris is at a moderate 
risk of extinction within this significant portion of its range.
Distinct Population Segment (DPS) Analysis
    In accordance with the SPR policy, if a species is determined to be 
threatened or endangered in a significant portion of its range, and the 
population in that significant portion is a valid distinct population 
segment (DPS), NMFS will list the DPS rather than the entire taxonomic 
species or subspecies. Because the Indo-Pacific and eastern Pacific 
represents a significant portion of the range of the species, and this 
portion is at a risk of extinction that is higher than ``low,'' we 
performed a DPS analysis on the population within this portion to see 
if it qualifies as a valid DPS.
    The Services' policy on identifying DPSs (61 FR 4722; February 7, 
1996) identifies two criteria for DPS designations: (1) The population 
must be discrete in relation to the remainder of the taxon (species or 
subspecies) to which it belongs; and (2) the population must be 
``significant'' (as that term is used in the context of the DPS policy, 
which is different from its usage under the SPR policy) to the 
remainder of the taxon to which it belongs.
    In terms of discreteness, a population segment of a vertebrate 
species may be considered discrete if it satisfies either one of the 
following conditions: (1) ``It is markedly separated from other 
populations of the same taxon as a consequence of physical, 
physiological, ecological, or behavioral factors. Quantitative measures 
of genetic or morphological discontinuity may provide evidence of this 
separation''; or (2) ``it is delimited by international governmental 
boundaries within which differences in control of exploitation, 
management of habitat, conservation status, or regulatory mechanisms 
exist that are significant in light of section 4(a)(1)(D)'' of the ESA 
(61 FR 4722; February 7, 1996).
    Research on the genetics of the species, which may provide evidence 
of discreteness between populations, is ongoing. As discussed 
previously in this finding, while there may be evidence of a potential 
M. birostris subspecies, or new manta species, found off the 
Yucat[aacute]n coast in the Gulf of Mexico, the study by Hinojosa-
Alvarez et al. (2016) also showed that some of the Yucat[aacute]n manta 
rays found in the area shared haplotypes with M. birostris samples from 
the Indo-Pacific and eastern Pacific. Additionally, based on nuclear 
DNA, the Yucat[aacute]n samples were consistent with the M. birostris 
samples from the Indo-Pacific and eastern Pacific portions of its 
range. This is the only study that we are aware of that has compared 
potential genetic differences between ocean basins for giant manta 
rays. Given the available data, we do not find evidence to indicate 
genetic discreteness between M. birostris in the Atlantic and M. 
birostris in the Indo-Pacific and eastern Pacific.
    In terms of physical, physiological, morphological, ecological, 
behavioral, and regulatory factors, there is no evidence that the Indo-
Pacific and eastern Pacific population of M. birostris is markedly 
separate from the population in the Atlantic. There is no evidence of 
differences in the morphology or physiology between the populations, 
nor any information to indicate changes in habitat use or behavior 
across ocean basins. Also, given that the species is highly migratory 
and pelagic, with no identified barriers to movement, these populations 
cannot be delimited by international governmental boundaries. As such, 
we find that the M. birostris population in the Indo-Pacific and 
eastern Pacific does not meet the discreteness criteria of the DPS 
policy, and, thus, is not a valid DPS.

Reef Manta Ray

    Overall, the species' life history characteristics increase its 
inherent vulnerability to depletion. Its tendency towards site fidelity 
and high residency rates suggests that there may be little gene flow 
between subpopulations, meaning that reestablishment after depletion is 
unlikely. Additionally, because these aggregations tend to be small, 
even light fishing may lead to population depletion. However, despite 
these inherent risks, the species does not appear subjected to 
significant threats that are causing declines, or likely to cause 
declines, to the point where the species would be at risk of 
extinction. As mentioned in the threats analysis, targeted fishing of 
the species has only been observed in a select few locations, and its 
identification in bycatch is limited. The majority of the known M. 
alfredi subpopulations, particularly throughout the western and Central 
Pacific, while small, are protected from fishing mortality and appear 
stable. Some of the larger known M. alfredi subpopulations, such as off 
the Maldives (n = 3,300-9,677 individuals) and Western Australia (n = 
1,200-1,500 individuals), are not subject to directed fishing, with 
Australia's overall population considered to be one of the world's 
healthiest. While climate change may alter aspects of the habitat and 
food resources of the species, the subsequent impact on the species is 
highly uncertain. Thus, based on the above evaluation of demographic 
risks and threats to the species, we find that the reef manta ray is 
likely to be at a low overall risk of extinction.
SPR Analysis
    As was done for the giant manta ray, we must conduct an SPR 
analysis to determine if the species is in danger of extinction, or 
likely to become so within the foreseeable future, in a significant 
portion of its range. In applying the policy, we first examined where 
threats are concentrated to evaluate whether the species is at risk of 
extinction within those portions. Targeted fishing and subsequent 
declines in populations of M. alfredi are known from waters off 
Mozambique and the Philippines, and the species has also been 
identified in bycatch from Indonesia, Papua New Guinea, and Kiribati. 
However, with the exception of the southern Mozambique population, the 
extent of decline of the

[[Page 3712]]

species throughout these other areas has not been quantified. But while 
the rate of decline is unknown, fishing pressure on the species 
continues in these portions of range and, combined with the species' 
demographic risks of isolated, small populations and extremely low 
productivity, these threats are likely placing these populations on a 
trajectory toward a higher risk of extinction.
    The second question that needs to be addressed in the SPR analysis 
is whether these portions can be considered ``significant.'' Without 
these portions, would the species be in danger of extinction, or likely 
to become so in the foreseeable future, throughout all of its range? We 
find that this is unlikely to be the case. Even if these populations 
were gone, the species would still exist as small, isolated populations 
throughout the Indo-Pacific. There is no evidence of source-sink 
dynamics between these portions and other areas, which could affect the 
survival of the species. In fact, the only indication of a potential 
source-sink dynamic was hypothesized for the M. alfredi population off 
Yaeyama, Japan, which Kashiwagi (2014) found is presently increasing, 
indicating no risk of loss to this population. In fact, many of the M. 
alfredi populations outside of the portions identified above, while 
small in size, are presently thought to be stable or increasing. 
Additionally, these populations, such as the largest identified M. 
alfredi population, off the Maldives, benefit from national protections 
that prohibit the fishing, landing, or selling of the species. Because 
these populations occur nearshore, and the species exhibits high 
residency rates and site-fidelity behavior, these protections will be 
adequate to prevent overutilization of the species through the 
foreseeable future. As such, even without the portions identified 
above, the species will unlikely be in danger of extinction throughout 
all of its range now or in the foreseeable future.
    Thus, under the SPR policy, we could not identify any portions of 
the species' range that meet both criteria (i.e., the portion is 
biologically significant and the species may be in danger of extinction 
in that portion, or likely to become so within the foreseeable future). 
Therefore, we find that our conclusion about the species' overall risk 
of extinction does not change and conclude that M. alfredi is likely to 
be at a low risk of extinction throughout its range.

Protective Efforts

    There are many conservation efforts presently ongoing to collect 
research on manta ray life history, ecology, and biology, and to raise 
awareness of threats to manta rays (see Miller and Klimovich (2016) for 
detailed discussion). The available research and citizen science data 
that have resulted from these conservation efforts have already been 
considered in the above analysis, and future research activities will 
continue to provide valuable information on these manta ray species. 
Additionally, the efforts by these organizations to educate the public, 
such as through awareness campaigns, could eventually lead to decreases 
in the demand for manta ray products. For example, Lawson et al. 
(2016), citing unpublished data, noted an 18-month awareness-raising 
campaign conducted in 2015 in Guangzhou, China, that seemed to indicate 
a level of success in decreasing consumer demand for gill rakers, 
which, in turn, decreased the interest of traders to carry gill plates 
in the future. While more monitoring of trade and consumer behavior is 
required to evaluate the success of these efforts, it may indicate that 
awareness-raising campaigns could be successful tools for influencing 
customer behavior. With demand reduction viewed as a potential avenue 
to indirectly reduce fishing pressure on manta rays, these campaigns 
may ultimately help decrease the main threat to the species (Lawson et 
al. 2016).
    Awareness campaigns are also being used to educate the public on 
appropriate tourist behavior during manta ray dives, which can help 
decrease potential negative impacts of tourism activities on manta 
rays. As mentioned previously, best practice codes of conduct have been 
developed by a number of organizations and are increasingly being used 
by dive operators at a number of popular manta ray diving sites, 
including Kona, Hawaii, Western Australia, Mozambique, Bora Bora, and 
the Maldives, to promote the safe viewing of manta rays.
    While we find that these efforts will help increase the scientific 
knowledge and promote public awareness about manta rays, with the 
potential (but not certainty) to decrease the impacts of specific 
threats in the future, we do not find that these efforts have 
significantly altered the extinction risk for the giant manta ray to 
where it would not be at risk of extinction in the foreseeable future. 
However, we seek additional information on these and other conservation 
efforts in our public comment process (see below).

Determination

    Section 4(b)(1) of the ESA requires that NMFS make listing 
determinations based solely on the best scientific and commercial data 
available after conducting a review of the status of the species and 
taking into account those efforts, if any, being made by any state or 
foreign nation, or political subdivisions thereof, to protect and 
conserve the species. We have independently reviewed the best available 
scientific and commercial information including the petition, public 
comments submitted on the 90-day finding (81 FR 8874; February 23, 
2016), the status review report (Miller and Klimovich 2016), and other 
published and unpublished information, and have consulted with species 
experts and individuals familiar with manta rays. We considered each of 
the statutory factors to determine whether it presented an extinction 
risk to each species on its own, now or in the foreseeable future, and 
also considered the combination of those factors to determine whether 
they collectively contributed to the extinction risk of the species, 
now or in the foreseeable future.
    Based on our consideration of the best available scientific and 
commercial information, as summarized here and in Miller and Klimovich 
(2016), including our SPR and DPS analyses, we find that the giant 
manta ray (Manta birostris) is at a moderate risk of extinction within 
a significant portion of its range, with the species likely to become 
in danger of extinction within the foreseeable future throughout that 
portion. We did not find that the significant portion meets the 
criteria of a DPS. Therefore, we have determined that the giant manta 
ray meets the definition of a threatened species and, per the SPR 
policy, propose to list it is as such throughout its range under the 
ESA.
    Based on our consideration of the best available scientific and 
commercial information, as summarized here and in Miller and Klimovich 
(2016), we find that the reef manta ray (Manta alfredi) faces an 
overall low risk of extinction throughout its range. As previously 
explained, we could not identify any portion of the species' range that 
met both criteria of the SPR policy. Accordingly, the reef manta ray 
does not meet the definition of a threatened or endangered species, and 
thus, the reef manta ray does not warrant listing as threatened or 
endangered at this time. This is a final action on the aforementioned 
petition to list the reef

[[Page 3713]]

manta ray under the ESA, and, therefore, we do not solicit comments on 
it.

Effects of Listing

    Conservation measures provided for species listed as endangered or 
threatened under the ESA include recovery actions (16 U.S.C. 1533(f)); 
concurrent designation of critical habitat, if prudent and determinable 
(16 U.S.C. 1533(a)(3)(A)); Federal agency requirements to consult with 
NMFS under section 7 of the ESA to ensure their actions do not 
jeopardize the species or result in adverse modification or destruction 
of critical habitat should it be designated (16 U.S.C. 1536); and 
prohibitions on ``taking'' (16 U.S.C. 1538). Recognition of the 
species' plight through listing promotes conservation actions by 
Federal and state agencies, foreign entities, private groups, and 
individuals.

Identifying Section 7 Conference and Consultation Requirements

    Section 7(a)(2) (16 U.S.C. 1536(a)(2)) of the ESA and NMFS/USFWS 
regulations require Federal agencies to confer with us on actions 
likely to jeopardize the continued existence of species proposed for 
listing, or that result in the destruction or adverse modification of 
proposed critical habitat. If a proposed species is ultimately listed, 
Federal agencies must consult on any action they authorize, fund, or 
carry out if those actions may affect the listed species or its 
critical habitat and ensure that such actions do not jeopardize the 
species or result in adverse modification or destruction of critical 
habitat should it be designated. Examples of Federal actions that may 
affect the giant manta ray include, but are not limited to: Alternative 
energy projects, discharge of pollution from point sources, non-point 
source pollution, contaminated waste and plastic disposal, dredging, 
pile-driving, development of water quality standards, vessel traffic, 
military activities, and fisheries management practices.

Critical Habitat

    Critical habitat is defined in section 3 of the ESA (16 U.S.C. 
1532(3)) as: (1) The specific areas within the geographical area 
occupied by a species, at the time it is listed in accordance with the 
ESA, on which are found those physical or biological features (a) 
essential to the conservation of the species and (b) that may require 
special management considerations or protection; and (2) specific areas 
outside the geographical area occupied by a species at the time it is 
listed upon a determination that such areas are essential for the 
conservation of the species. ``Conservation'' means the use of all 
methods and procedures needed to bring the species to the point at 
which listing under the ESA is no longer necessary. Section 4(a)(3)(a) 
of the ESA (16 U.S.C. 1533(a)(3)(A)) requires that, to the extent 
prudent and determinable, critical habitat be designated concurrently 
with the listing of a species. Designations of critical habitat must be 
based on the best scientific data available and must take into 
consideration the economic, national security, and other relevant 
impacts of specifying any particular area as critical habitat. If we 
determine that it is prudent and determinable, we will publish a 
proposed designation of critical habitat for the giant manta ray in a 
separate rule. Public input on features and areas in U.S. waters that 
may meet the definition of critical habitat for the giant manta ray is 
invited.

Protective Regulations Under Section 4(d) of the ESA

    We are proposing to list the giant manta ray (Manta birostris) as a 
threatened species. In the case of threatened species, ESA section 4(d) 
leaves it to the Secretary's discretion whether, and to what extent, to 
extend the section 9(a) ``take'' prohibitions to the species, and 
authorizes us to issue regulations necessary and advisable for the 
conservation of the species. Thus, we have flexibility under section 
4(d) to tailor protective regulations, taking into account the 
effectiveness of available conservation measures. The 4(d) protective 
regulations may prohibit, with respect to threatened species, some or 
all of the acts which section 9(a) of the ESA prohibits with respect to 
endangered species. We are not proposing such regulations at this time, 
but may consider potential protective regulations pursuant to section 
4(d) for the giant manta ray in a future rulemaking. In order to inform 
our consideration of appropriate protective regulations for the 
species, we seek information from the public on the threats to giant 
manta rays and possible measures for their conservation.

Role of Peer Review

    The intent of peer review is to ensure that listings are based on 
the best scientific and commercial data available. In December 2004, 
the Office of Management and Budget (OMB) issued a Final Information 
Quality Bulletin for Peer Review establishing minimum peer review 
standards, a transparent process for public disclosure of peer review 
planning, and opportunities for public participation. The OMB Bulletin, 
implemented under the Information Quality Act (Pub. L. 106-554), is 
intended to enhance the quality and credibility of the Federal 
government's scientific information, and applies to influential or 
highly influential scientific information disseminated on or after June 
16, 2005. To satisfy our requirements under the OMB Bulletin, we 
obtained independent peer review of the status review report. 
Independent specialists were selected from the academic and scientific 
community for this review. All peer reviewer comments were addressed 
prior to dissemination of the status review report and publication of 
this proposed rule.

Public Comments Solicited on Listing

    To ensure that the final action resulting from this proposal will 
be as accurate and effective as possible, we solicit comments and 
suggestions from the public, other governmental agencies, the 
scientific community, industry, environmental groups, and any other 
interested parties. Comments are encouraged on this proposal (See DATES 
and ADDRESSES). Specifically, we are interested in information 
regarding: (1) New or updated information regarding the range, 
distribution, and abundance of the giant manta ray; (2) new or updated 
information regarding the genetics and population structure of the 
giant manta ray; (3) habitat within the range of the giant manta ray 
that was present in the past but may have been lost over time; (4) new 
or updated biological or other relevant data concerning any threats to 
the giant manta ray (e.g., post-release mortality rates, landings of 
the species, illegal taking of the species); (5) current or planned 
activities within the range of the giant manta ray and their possible 
impact on the species; (6) recent observations or sampling of the giant 
manta ray; and (7) efforts being made to protect the giant manta ray.

Public Comments Solicited on Critical Habitat

    We request information describing the quality and extent of 
habitats for the giant manta ray, as well as information on areas that 
may qualify as critical habitat for the species in U.S. waters. 
Specific areas that include the physical and biological features 
essential to the conservation of the species, where such features may 
require special management considerations or protection, should be 
identified. Areas outside the occupied geographical area should also be 
identified, if such areas themselves are essential to the

[[Page 3714]]

conservation of the species. ESA implementing regulations at 50 CFR 
424.12(g) specify that critical habitat shall not be designated within 
foreign countries or in other areas outside of U.S. jurisdiction. 
Therefore, we request information only on potential areas of critical 
habitat within waters under U.S. jurisdiction.
    Section 4(b)(2) of the ESA requires the Secretary to consider the 
``economic impact, impact on national security, and any other relevant 
impact'' of designating a particular area as critical habitat. Section 
4(b)(2) also authorizes the Secretary to exclude from a critical 
habitat designation those particular areas where the Secretary finds 
that the benefits of exclusion outweigh the benefits of designation, 
unless excluding that area will result in extinction of the species. 
For features and areas potentially qualifying as critical habitat, we 
also request information describing: (1) Activities or other threats to 
the essential features or activities that could be affected by 
designating them as critical habitat; and (2) the positive and negative 
economic, national security and other relevant impacts, including 
benefits to the recovery of the species, likely to result if these 
areas are designated as critical habitat. We seek information regarding 
the conservation benefits of designating areas within waters under U.S. 
jurisdiction as critical habitat. In keeping with the guidance provided 
by OMB (2000; 2003), we seek information that would allow the 
monetization of these effects to the extent possible, as well as 
information on qualitative impacts to economic values.
    Data reviewed may include, but are not limited to: (1) Scientific 
or commercial publications; (2) administrative reports, maps or other 
graphic materials; (3) information received from experts; and (4) 
comments from interested parties. Comments and data particularly are 
sought concerning: (1) Maps and specific information describing the 
amount, distribution, and use type (e.g., foraging or migration) by the 
giant manta ray, as well as any additional information on occupied and 
unoccupied habitat areas; (2) the reasons why any habitat should or 
should not be determined to be critical habitat as provided by sections 
3(5)(A) and 4(b)(2) of the ESA; (3) information regarding the benefits 
of designating particular areas as critical habitat; (4) current or 
planned activities in the areas that might be proposed for designation 
and their possible impacts; (5) any foreseeable economic or other 
potential impacts resulting from designation, and in particular, any 
impacts on small entities; (6) whether specific unoccupied areas may be 
essential to provide additional habitat areas for the conservation of 
the species; and (7) potential peer reviewers for a proposed critical 
habitat designation, including persons with biological and economic 
expertise relevant to the species, region, and designation of critical 
habitat.

References

    A complete list of the references used in this proposed rule is 
available upon request (see ADDRESSES).

Classification

National Environmental Policy Act

    The 1982 amendments to the ESA, in section 4(b)(1)(A), restrict the 
information that may be considered when assessing species for listing. 
Based on this limitation of criteria for a listing decision and the 
opinion in Pacific Legal Foundation v. Andrus, 675 F. 2d 825 (6th Cir. 
1981), NMFS has concluded that ESA listing actions are not subject to 
the environmental assessment requirements of the National Environmental 
Policy Act (NEPA).

Executive Order 12866, Regulatory Flexibility Act, and Paperwork 
Reduction Act

    As noted in the Conference Report on the 1982 amendments to the 
ESA, economic impacts cannot be considered when assessing the status of 
a species. Therefore, the economic analysis requirements of the 
Regulatory Flexibility Act are not applicable to the listing process. 
In addition, this proposed rule is exempt from review under Executive 
Order 12866. This proposed rule does not contain a collection-of-
information requirement for the purposes of the Paperwork Reduction 
Act.

Executive Order 13132, Federalism

    In accordance with E.O. 13132, we determined that this proposed 
rule does not have significant Federalism effects and that a Federalism 
assessment is not required. In keeping with the intent of the 
Administration and Congress to provide continuing and meaningful 
dialogue on issues of mutual state and Federal interest, this proposed 
rule will be given to the relevant governmental agencies in the 
countries in which the species occurs, and they will be invited to 
comment. As we proceed, we intend to continue engaging in informal and 
formal contacts with the states, and other affected local, regional, or 
foreign entities, giving careful consideration to all written and oral 
comments received.

List of Subjects in 50 CFR Part 223

    Endangered and threatened species.

    Dated: January 5, 2017.
Samuel D. Rauch, III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.

    For the reasons set out in the preamble, 50 CFR part 223 is 
proposed to be amended as follows:

PART 223--THREATENED MARINE AND ANADROMOUS SPECIES

0
1. The authority citation for part 223 continues to read as follows:

    Authority: 16 U.S.C. 1531-1543; subpart B, Sec.  223.201-202 
also issued under 16 U.S.C. 1361 et seq.; 16 U.S.C. 5503(d) for 
Sec.  223.206(d)(9).

0
2. In Sec.  223.102, in the table in paragraph (e) add a new entry for 
``ray, giant manta'' in alphabetical order by common name under the 
``Fishes'' subheading to read as follows:


Sec.  223.102  Enumeration of threatened marine and anadromous species.

* * * * *
    (e) * * *

[[Page 3715]]



----------------------------------------------------------------------------------------------------------------
                              Species \1\
-----------------------------------------------------------------------  Citation(s) for   Critical
                                                Description  of listed       listing        habitat   ESA  rules
      Common name           Scientific name              entity         determination(s)
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
Fishes
 
                                                  * * * * * * *
Ray, giant manta......  Manta birostris.......  Entire species........  [Insert Federal   NA........  NA.
                                                                         Register page
                                                                         where the
                                                                         document
                                                                         begins],
                                                                         [Insert date of
                                                                         publication
                                                                         when published
                                                                         as a final
                                                                         rule].
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------
\1\ Species includes taxonomic species, subspecies, distinct population segments (DPSs) (for a policy statement,
  see 61 FR 4722, February 7, 1996), and evolutionarily significant units (ESUs) (for a policy statement, see 56
  FR 58612, November 20, 1991).

[FR Doc. 2017-00370 Filed 1-11-17; 8:45 am]
BILLING CODE 3510-22-P