[Federal Register Volume 87, Number 218 (Monday, November 14, 2022)]
[Notices]
[Pages 68236-68268]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-24493]



[[Page 68235]]

Vol. 87

Monday,

No. 218

November 14, 2022

Part II





Department of Commerce





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National Oceanic and Atmospheric Administration





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Endangered and Threatened Wildlife and Plants; 12-Month Finding on a 
Petition To List the Shortfin Mako Shark (Isurus oxyrinchus) as 
Threatened or Endangered Under the Endangered Species Act; Notice

  Federal Register / Vol. 87 , No. 218 / Monday, November 14, 2022 / 
Notices  

[[Page 68236]]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[Docket No. 221103-0232; RTID 0648-XR116]


Endangered and Threatened Wildlife and Plants; 12-Month Finding 
on a Petition To List the Shortfin Mako Shark (Isurus oxyrinchus) as 
Threatened or Endangered Under the Endangered Species Act

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

ACTION: Notice of 12-month finding and availability of status review 
document for the shortfin mako shark (Isurus oxyrinchus).

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SUMMARY: We, NMFS, have completed a comprehensive status review under 
the Endangered Species Act (ESA) for the shortfin mako shark (Isurus 
oxyrinchus) in response to a petition from Defenders of Wildlife to 
list the species. After reviewing the best scientific and commercial 
data available, including the Status Review Report, we have determined 
that listing the shortfin mako shark as a threatened or endangered 
species under the ESA is not warranted.

DATES: This finding was made on November 14, 2022.

ADDRESSES: The Status Review Report associated with this determination, 
its references, and the petition can be accessed electronically online 
at: https://www.fisheries.noaa.gov/species/shortfin-mako-shark#conservation-management.

FOR FURTHER INFORMATION CONTACT: Adrienne Lohe, NMFS Office of 
Protected Resources, 301-427-8442.

SUPPLEMENTARY INFORMATION:

Background

    On January 25, 2021, we received a petition from Defenders of 
Wildlife to list the shortfin mako shark (Isurus oxyrinchus) as a 
threatened or endangered species under the ESA. The petition asserted 
that the shortfin mako shark is threatened by four of the five ESA 
section 4(a)(1) factors: (1) the present or threatened destruction, 
modification, or curtailment of its habitat or range; (2) 
overutilization for commercial and recreational purposes; (3) 
inadequacy of existing regulatory mechanisms; and (4) other natural or 
manmade factors.
    On April 15, 2021, NMFS published a 90-day finding for the shortfin 
mako shark with our determination that the petition presented 
substantial scientific and commercial information indicating that the 
petitioned action may be warranted (86 FR 19863). We also announced the 
initiation of a status review of the species, as required by section 
4(b)(3)(A) of the ESA, and requested information to inform the agency's 
decision on whether this species warrants listing as endangered or 
threatened under the ESA. We received information from the public in 
response to the 90-day finding and incorporated the information into 
both the Status Review Report (Lohe et al. 2022) and this 12-month 
finding.

Listing Determinations Under the ESA

    We are responsible for determining whether species are threatened 
or endangered under the ESA (16 U.S.C. 1531 et seq.). To be considered 
for listing under the ESA, a group of organisms must constitute a 
``species,'' which is defined in section 3 of the ESA to include any 
subspecies of fish or wildlife or plants, and any distinct population 
segment (DPS) of any species of vertebrate fish or wildlife which 
interbreeds when mature (16 U.S.C. 1532(16)). 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 (``DPS Policy,'' 61 FR 4722). The joint DPS Policy identifies 
two elements that must be considered when identifying a DPS: (1) The 
discreteness of the population segment in relation to the remainder of 
the taxon to which it belongs; and (2) the significance of the 
population segment to the remainder of the taxon 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 (16 U.S.C. 1532(6), 16 U.S.C. 
1532(20)). Thus, in the context of the ESA, we interpret an 
``endangered species'' to be one that is presently in danger of 
extinction. A ``threatened species,'' on the other hand, is not 
presently in danger of extinction, but is likely to become so in the 
foreseeable future. In other words, the primary statutory difference 
between a threatened and endangered species is the timing of when a 
species is in danger of extinction, either presently (endangered) or in 
the foreseeable future (threatened).
    Under section 4(a)(1) of the ESA, we must determine whether any 
species is endangered or threatened as a result of any one or a 
combination of any of the following factors: (A) the present or 
threatened destruction, modification, or curtailment of its habitat or 
range; (B) overutilization for commercial, recreational, scientific, or 
educational purposes; (C) disease or predation; (D) the inadequacy of 
existing regulatory mechanisms; or (E) other natural or manmade factors 
affecting its continued existence (16 U.S.C. 1533(a)(1)). We are also 
required to make listing determinations based solely on the best 
scientific and commercial data available, after conducting a review of 
the species' status and after taking into account efforts, if any, 
being made by any state or foreign nation (or subdivision thereof) to 
protect the species (16 U.S.C. 1533(b)(1)(A)).

Status Review

    To determine whether the shortfin mako shark warrants listing under 
the ESA, we completed a Status Review Report, which summarizes 
information on the species' taxonomy, distribution, abundance, life 
history, and biology; identifies threats or stressors affecting the 
status of the species; and assesses the species' current and future 
extinction risk. We appointed a biologist in the Office of Protected 
Resources Endangered Species Conservation Division to compile and 
complete a scientific review of the best available information on the 
shortfin mako shark, including information received in response to our 
request for information (86 FR 19863, April 15, 2021). Next, we 
convened an Extinction Risk Analysis (ERA) Team of biologists and shark 
experts to assess the threats affecting the shortfin mako shark, as 
well as demographic risk factors (abundance, productivity, spatial 
distribution, and diversity), using the information in the scientific 
review. The Status Review Report presents the ERA Team's professional 
judgment of the extinction risk facing the shortfin mako shark but 
makes no recommendation as to the listing status of the species. The 
Status Review Report is available electronically (see ADDRESSES). 
Information from the Status Review Report is summarized below in the 
Biological Review section, and the results of the ERA from the Status 
Review Report are discussed below.
    The Status Review Report was subject to independent peer review as 
required by the Office of Management and Budget Final Information 
Quality Bulletin for Peer Review (M-05-03; December 16, 2004). The 
Status Review

[[Page 68237]]

Report was peer reviewed by three independent specialists selected from 
the academic and scientific community with expertise in shark biology, 
conservation, and management, and specific knowledge of shortfin mako 
sharks. The peer reviewers were asked to evaluate the adequacy, 
appropriateness, and application of data used in the Status Review 
Report, as well as the findings made in the ``Assessment of Extinction 
Risk'' section of the report. All peer reviewer comments were addressed 
prior to finalizing the Status Review Report.
    We subsequently reviewed the Status Review Report, its cited 
references, and peer review comments, and conclude the Status Review 
Report, upon which this 12-month finding is based, provides the best 
available scientific and commercial information on the shortfin mako 
shark. Much of the information discussed below on the species' biology, 
distribution, abundance, threats, and extinction risk is attributable 
to the Status Review Report. Following our review of the Status Review 
Report and consideration of peer review comments, we conclude, however, 
that the ERA Team's foreseeable future of 25 years for the shortfin 
mako shark is not adequately justified. Each of the three peer 
reviewers recommended evaluating the species' risk of extinction over a 
longer time horizon. Based on these peer review comments and our review 
of the ERA Team's selection of 25 years as the foreseeable future, we 
have completed an independent determination of the foreseeable future 
(see Extinction Risk Analysis). For this reason, while we rely on the 
ERA Team's assessment of the species' present risk of extinction, we 
have supplemented the assessment of the species' risk of extinction 
within the foreseeable future. We have also independently applied the 
statutory provisions of the ESA, including evaluation of the factors 
set forth in section 4(a)(1)(A)-(E), our regulations regarding listing 
determinations,\1\ and relevant policies identified herein in making 
the 12-month finding determination.
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    \1\ On July 5, 2022, the United States District Court for the 
Northern District of California issued an order vacating the ESA 
section 4 implementing regulations that were revised or added to 50 
CFR 424 in 2019 (``2019 regulations,'' see 84 FR 45020, August 27, 
2019) although making no findings on the merits. On September 21, 
2022, the U.S. Court of Appeals for the Ninth Circuit granted a 
temporary stay of the district court's July 5 order. As a result, 
the 2019 regulations are once again in effect, and we are applying 
the 2019 regulations here. For purposes of this determination, we 
considered whether the analysis or its conclusions would be any 
different under the pre-2019 regulations. We have determined that 
our analysis and conclusions presented here would not be any 
different.
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Biological Review

Taxonomy and Species Description

    The shortfin mako shark belongs to the family Lamnidae in the order 
Lamniformes, the mackerel sharks (ITIS 2021). Lamnid sharks are 
littoral to epipelagic with broad distributions in tropical to cold-
temperate waters (Compagno 1984). They are fast-swimming and have a 
modified circulatory system to maintain internal temperatures warmer 
than the surrounding water (Compagno 1984). The shortfin mako shark 
belongs to the genus Isurus and only has a single living cogeneric 
species, the longfin mako shark (Isurus paucus). The species is 
relatively large, reaching a maximum total length (TL) of about 445 
centimeters (cm) (Weigmann 2016), and has a moderately slender, 
spindle-shaped body with a conical snout (Compagno 1984). Its pectoral 
fins are narrow-tipped and moderately broad and long (considerably 
shorter than the length of the head) as compared to the very long 
pectoral fins of the longfin mako shark, which also has a less pointed 
snout and dusky underside (Compagno 1984; Ebert et al. 2013). The first 
dorsal fin is large and the second is very small and pivoting (Compagno 
1984). The upper and lower lobes of the caudal fin are of nearly equal 
size, which is reflected in the genus name Isurus from the Greek words 
for ``equal tail.'' The teeth are large and bladelike without 
serrations, and the tips of the anterior teeth are strongly reflexed 
(Compagno 1984). The dorsal surface of the body is dark blue and the 
ventral side is white (Compagno 1984).

Distribution

    The shortfin mako shark is a globally distributed pelagic species, 
occurring across all temperate and tropical ocean waters from about 
50[deg] N (up to 60[deg] N in the northeast Atlantic) to 50[deg] S and 
across a range of marine habitats (Rigby et al. 2019; Santos et al. 
2020). Compagno (2001) provides the following description of the 
species' global distribution: in the western Atlantic, the species 
occurs from the Gulf of Maine to southern Brazil and possibly northern 
Argentina, including Bermuda, the Caribbean, and the Gulf of Mexico. In 
the eastern Atlantic, the range spans from Norway, the British Isles, 
and the Mediterranean to Morocco, Azores, Western Sahara, Mauritania, 
Senegal, C[ocirc]te d'Ivoire, Ghana, southern Angola, probably Namibia, 
and the west coast of South Africa. In the Indo-Pacific basin, the 
species is found from the east coast of South Africa, Mozambique, 
Madagascar, Mauritius and Kenya north to the Red Sea, and east to 
Maldives, Iran, Oman, Pakistan, India, Indonesia, Viet Nam, China, 
Taiwan, North Korea, South Korea, Japan, Russia, Australia (all states 
and entire coast except for Arafura Sea, Gulf of Carpentaria and Torres 
Strait), New Zealand (including Norfolk Island), New Caledonia, and 
Fiji. In the central Pacific, the shortfin mako shark occurs from south 
of the Aleutian Islands to the Society Islands, including the Hawaiian 
Islands, and in the eastern Pacific, from southern California (and 
sometimes as far north as Washington State) south to Mexico, Costa 
Rica, Ecuador, Peru, and central Chile. Rare observations outside of 
this range have also been made, for example in waters of British 
Columbia (Gillespie and Saunders 1994).

Habitat Use

    The shortfin mako shark is known to travel long distances in and 
between open ocean, continental shelf, shelf edge, and shelf slope 
habitats (Rogers et al. 2015b; Santos et al. 2021), making extensive 
long-distance straight-line movements of several thousand kilometers 
(km) (Francis et al. 2019). From traditional dart and fin tagging data, 
maximum recorded time at liberty is 12.8 years, and the maximum 
straight-line distance between tag and recapture localities is 3,043 
nautical miles (5,636 km) (Kohler and Turner 2019). Shorter-term 
electronic tagging results from several studies indicate that the 
species commonly makes roundtrip migratory movements of more than 
20,000 km, with one individual found to undertake an extended migration 
of 25,550 km over a period of 551 days (Rogers et al. 2015b; Francis et 
al. 2019). While the species has also demonstrated fidelity to small 
geographic areas on or near continental shelves and coastal areas of 
high productivity, this fidelic behavior is rarely observed in the open 
ocean (Rogers et al. 2015b; Corrigan et al. 2018; Francis et al. 2019; 
Gibson et al. 2021). Recent research demonstrates that the species 
regularly switches between these states of activity (i.e., resident or 
fidelity behavior state and traveling state), spending nearly half 
their time (44-47 percent) in residency and slightly less than half 
their time (35-42 percent) in transit (Rogers et al. 2015b; Francis et 
al. 2019). It is unknown whether these behavioral states are tied to 
specific behaviors such as feeding or breeding. Furthermore, this 
behavioral switching may be affected by factors including

[[Page 68238]]

environmental variation, spatial areas of sampling, or biotic factors; 
therefore, these findings may not be representative of the entire 
species, especially across time and space.
    The vertical distribution of shortfin mako sharks is related to 
numerous environmental variables, including water temperature, 
dissolved oxygen (DO) concentration, time of day, prey availability, 
and lunar phase. The species typically occupies waters ranging between 
17 [deg]C and 22 [deg]C (Casey and Kohler 1992; Nasby-Lucas et al. 
2019; Santos et al. 2020, 2021), though it has a broad thermal 
tolerance and has been shown to also occupy waters from 10 [deg]C 
(Abascal et al. 2011) to 31 [deg]C (Vaudo et al. 2017). Like other 
lamnid sharks, the shortfin mako shark has counter-current circulation 
and is a red muscle endotherm, meaning that it can maintain the 
temperature of its slow-twitch, aerobic red muscle significantly above 
ambient temperature (Watanabe et al. 2015). Red muscle endothermy 
allows the species to tolerate a greater range of water temperatures, 
cruise faster, and have greater maximum annual migration lengths than 
fish without this trait (Watanabe et al. 2015). The high energetic cost 
of endothermy is suggested to be outweighed by benefits such as 
increased foraging success, prey encounter rates, and access to other 
seasonally available resources (Watanabe et al. 2015). The routine 
metabolic rate and maximum metabolic rate of shortfin mako sharks is 
among the highest measured for any shark species (Sepulveda et al. 
2007), which may explain why the shortfin mako shark typically inhabits 
waters with DO concentrations of at least 3 milliliters per liter and 
avoids areas of low DO (Abascal et al. 2011). Individuals primarily 
occupy the upper part of the water column, but dive to depths of 
several hundred meters (m) (as deep as 979.5 m reported by Santos et 
al. (2021)), allowing them to forage for mesopelagic fishes and squid, 
though dives may have other functions including navigation (Holts and 
Bedford 1993; Francis et al. 2019). There is evidence that illumination 
from a full moon causes shortfin mako sharks to move into deeper water 
in pursuit of prey (Lowry et al. 2007). ``Bounce'' or ``yo-yo'' diving 
behavior, in which individuals repeatedly descend to deeper water and 
then ascend to shallow depths, has been regularly observed in both 
adults and young-of-the-year (YOY) (Sepulveda et al. 2004; Abascal et 
al. 2011; Vaudo et al. 2016; Santos et al. 2021). This type of diving 
behavior may be associated with feeding, behavioral thermoregulation, 
energy conservation, and navigation (Klimley et al. 2002; Sepulveda et 
al. 2004). Tagging studies have shown that the species typically spends 
more time in deeper, colder water during the daytime, and moves to 
shallower, warmer waters at night (Holts and Bedford 1993; Klimley et 
al. 2002; Sepulveda et al. 2004; Loefer et al. 2005; Stevens et al. 
2010; Abascal et al. 2011; Nasby-Lucas et al. 2019). These diel 
vertical migrations are typically attributed to the pursuit of prey. 
However, other studies indicate no significant changes in vertical 
distribution between daytime and nighttime (Abascal et al. 2011, Santos 
et al. 2020). Larger individuals can dive to deeper depths than smaller 
individuals (Sepulveda et al. 2004), and juveniles specifically tend to 
spend much of their time in shallower, warmer water (Holts and Bedford 
1993; Nosal et al. 2019).
    There is some evidence that certain ocean currents and features may 
limit movement patterns, including the Mid-Atlantic ridge separating 
the western and eastern Atlantic (Casey and Kohler 1992 using 
conventional tagging data from 231 recaptured shortfin mako sharks over 
a 28-year period; Santos et al. 2020 using satellite telemetry for 41 
shortfin mako sharks over a period of between 30 and 120 days), and the 
Gulf Stream separating the North Atlantic and the Gulf of Mexico/
Caribbean Sea (Vaudo et al. 2017 using satellite telemetry for 26 
shortfin mako sharks over a period of 78-527 days). However, 
conventional tagging data indicates that movement does occur across 
these features. Data from the NMFS Cooperative Shark Tagging Program 
(n=1,148 recaptured shortfin mako sharks) over a 52-year period show 
evidence of the species crossing the Mid-Atlantic Ridge demonstrating 
exchange between the western and eastern Atlantic (Kohler and Turner 
2019). In fact, individual shortfin mako sharks (n = 104) that made 
long distance movements (>1,000 nautical miles) while at liberty for 
less than one year were primarily tagged off the coast of the U.S. 
Northeast and were recaptured in the Gulf of Mexico, Caribbean Sea, 
mid-Atlantic Ocean, and off Portugal, Morocco, and Western Sahara 
(Kohler and Turner 2019). In the Pacific, tagging data supports east-
west mixing in the north and minimal east-west mixing in the south 
(Sippel et al. 2016 using conventional tagging data from 704 recaptured 
shortfin mako sharks since 1968; Corrigan et al. 2018 using satellite 
telemetry data of 13 individuals over a period of 249-672 days). Trans-
equatorial movement appears to be uncommon based on tagging studies 
(Sippel et al. 2016; Corrigan et al. 2018), but tagged shortfin mako 
sharks have been recorded crossing the equator (Rogers et al. 2015a; 
Santos et al. 2021).
    The locations of mating grounds and other reproductive areas are 
not well known for the shortfin mako shark, although the distribution 
of the youngest age classes may indicate potential pupping and nursery 
areas. Casey and Kohler (1992) observed YOY shortfin mako sharks 
offshore in the Gulf of Mexico, hypothesizing that pups are born 
offshore in the Northwest Atlantic to protect them from predation by 
large sharks, including other makos. Bite marks observed on mature 
females caught in the Gulf of Mexico may have resulted from mating 
behavior, indicating that the area may also be a mating ground (Gibson 
et al. 2021). The presence of mature and pregnant females in the Gulf 
of Mexico provides further support that this may be a gestation and 
parturition ground for the species. However, fisheries data suggests 
that pupping is geographically widespread in the Northwest Atlantic 
given that neonates are widely distributed along the coast of North 
America and largely overlap with the distribution of older immature 
sharks and adults (Natanson et al. 2020). Excursions of tagged shortfin 
mako sharks towards the shelf and slope waters of the Subtropical 
Convergence Zone, the Canary archipelago, and the northwestern African 
continental shelf, as well as aggregations of YOY shortfin mako sharks 
in these areas, may indicate that they serve as pupping or nursery 
grounds in the Northeast Atlantic (Maia et al. 2007; Natanson et al. 
2020; Santos et al. 2021). In the Eastern North Pacific, the Southern 
California Bight has been suggested as a nursery area as roughly 60 
percent of the catch here is made up by YOY and 2- to 4-year-old 
juveniles (Holts and Bedford 1993; Rodr[iacute]guez-Madrigal et al. 
2017; Nasby-Lucas et al. 2019). Farther south, the presence of many 
juveniles and some neonates near fishing camps in Baja California, 
Mexico, suggests that the area between Bah[iacute]a Magdalena and 
Laguna San Ignacio may also be a nursery ground for the shortfin mako 
shark (Conde-Moreno and Galvan-Magana 2006). Presence of small immature 
shortfin mako sharks off Caldera, Chile, suggests that this may be a 
pupping or nursery area for the Southeastern Pacific (Bustamante and 
Bennett 2013). The temperate waters of the south-west Indian Ocean have 
been shown to host high concentrations of

[[Page 68239]]

neonates and adults, suggesting that this area may be a nursery ground 
(Wu et al. 2021). Further, pregnant females have been observed in 
coastal waters off South Africa, strengthening the evidence that this 
area may be used for pupping or as a nursery (Groeneveld et al. 2014).

Diet and Feeding

    The shortfin mako shark is a large, active predator that feeds 
primarily on teleosts and also consumes cephalopods, other 
elasmobranchs, cetaceans, and crustaceans (Stillwell and Kohler 1982; 
Cort[eacute]s 1999; Maia et al. 2006; Gorni et al. 2012). It is 
estimated that shortfin mako sharks must consume 4.6 percent of their 
body weight per day to meet their high energetic demands (Wood et al. 
2009). Based on the shortfin mako shark's diet, the species has a 
trophic level of 4.3 out of 5.0 (tertiary consumers have a trophic 
level over 4.0, while plants have a trophic level of one), one of the 
highest of 149 species examined by Cort[eacute]s (1999) and comparable 
to other pelagic shark species such as common and bigeye thresher 
sharks (Alopias vulpinus and Alopias superciliosus), the salmon shark 
(Lamna ditropis), and the oceanic whitetip shark (Carcharhinus 
longimanus) (Bizzarro et al. 2017). Rogers et al. (2012) found evidence 
that the species targets specific prey despite high prey diversity; 
however, stable isotope analysis indicates that the species is a 
generalist predator (Maya Meneses et al. 2016). The degree of prey 
selectivity in any given individual's diet is likely strongly 
correlated with prey availability, with prey being consumed as 
encountered.
    The specific diet of the shortfin mako shark varies by life stage, 
geographic location, season, and oceanic habitat. In the Northwest 
Atlantic, bluefish (Pomatomus saltatrix) are a major inshore prey item 
for the species and have been estimated to make up 77.5 percent of diet 
by volume (Stillwell and Kohler 1982), and more recently, 92.6 percent 
of diet by weight (Wood et al. 2009). In the northeast Atlantic, 
teleosts made up over 90 percent of the species' diet by weight, and 
Clupeiformes and garpike (Belone belone) are common prey (Maia et al. 
2006). In the South Atlantic, teleosts are also dominant in the 
shortfin mako shark's diet (including Lepidocibium flavobruneum, 
Scomber colias, and Trichiruridae), while cephalopods of the orders 
Teuthida and Octopoda are also consumed (Gorni et al. 2012). In the 
northeast Pacific along the west coast of the United States, jumbo 
squid (Dosidicus gigas) and Pacific saury (Cololabis saira) are the two 
most important prey items, and other frequent teleost prey includes 
Pacific sardine (Sardinops sagax), Pacific mackerel (Scomber 
japonicus), jack mackerel (Trachurus symmetricus), and striped mullet 
(Mugil cephalus) (Preti et al. 2012). By contrast, YOY and juvenile 
shortfin mako sharks off Baja California Sur, Mexico, largely consume 
whitesnout searobin (Prionotus albirostris), Pacific mackerel (S. 
japonicus), and a variety of small squids (Velasco Tarelo 2005). As 
they age, larger teleost species and squids more commonly found in 
offshore pelagic waters become increasingly important, as evidenced by 
stable isotope analysis (Velasco Tarelo 2005). A large female shortfin 
mako shark recreationally caught off the coastline of the Southern 
California Bight was found to have eaten a California sea lion, 
Zalophus californianus, an event that does not appear uncommon based on 
previously documented pinnipeds in the stomachs of large shortfin mako 
sharks (Lyons et al. 2015). Shortfin mako sharks in the Indian Ocean 
prey on teleosts (Trachurus capensis and S. sagax), elasmobranchs 
(Rhizoprionodon acutus and Carcharhinus obscurus), and cephalopods 
(Loligo spp.) (Groeneveld et al. 2014). The dominant prey of shortfin 
mako sharks caught in coastal bather protection nets in the southwest 
Indian Ocean were elasmobranchs, while the diet of shortfin mako sharks 
caught in offshore longlines was dominated by teleosts (Groeneveld et 
al. 2014). As the size of individuals caught in coastal bather nets was 
significantly greater than those caught in offshore longlines, 
Groeneveld et al. (2014) suggest that larger prey attracts larger mako 
sharks to coastal waters.

Size and Growth

    Shortfin mako sharks are long-lived, and are estimated to reach 
maximum ages of at least 28-32 years based on vertebral band counts 
validated by bomb radiocarbon and tag-recapture studies (Natanson et 
al. 2006; Dono et al. 2015). Longevity in the Pacific has been 
estimated as high as 56 years (Chang and Liu 2009; Carreon-Zapiain et 
al. 2018). There is uncertainty in the use of vertebral band pair 
counting to determine age as some authors find evidence for or assume 
annual growth band deposition periodicity (Cailliet et al. 1983; 
Campana et al. 2002; Ardizzone et al. 2006; Bishop et al. 2006; Semba 
et al. 2009; Dono et al. 2015; Liu et al. 2018) while others find 
evidence for the deposition of two growth band pairs each year for 
either all (Pratt Jr. and Casey 1983) or their first five years of life 
(Wells et al. 2013). Kinney et al. (2016) used the recapture of an 
oxytetracycline-tagged adult male to validate annual band deposition in 
adult shortfin mako sharks, inferring that juveniles experience more 
rapid growth and, therefore, exhibit biannual band pair deposition. In 
addition, there is evidence that vertebral band pair counts do not 
accurately reflect age in older, large individuals (Harry 2018; 
Natanson et al. 2018). Due to inconsistent information on vertebral 
band deposition in the Pacific, the International Scientific Committee 
for Tuna and Tuna-like Species (ISC) Shark Working Group's 2018 stock 
assessment of shortfin mako sharks in the North Pacific treated data 
from the western North Pacific as having a constant band pair 
deposition rate and data from the eastern North Pacific as having a 
band pair deposition rate that changes from two to one band pairs per 
year after age 5. The 2017 stock assessment of North and South Atlantic 
shortfin mako sharks conducted by the International Commission for the 
Conservation of Atlantic Tunas (ICCAT) assumed annual band pair 
deposition based on Natanson et al. (2006).
    Shortfin mako sharks exhibit slow growth rates. Growth coefficient 
(K) estimates range from 0.043-0.266 year-\1\ in the 
Atlantic Ocean, 0.0154-0.16 year-\1\ in the Pacific Ocean, 
and 0.075-0.15 year-\1\ in the Indian Ocean (Pratt Jr. and 
Casey 1983, Ribot-Carballal et al. 2005, Natanson et al. 2006, Bishop 
et al. 2006, Cerna and Licandeo 2009, Semba et al. 2009, Groeneveld et 
al. 2014, Liu et al. 2018). Males and females have similar growth rates 
until a certain point, when male growth slows down compared to female 
growth. This has been estimated to occur at 7 years of age in the 
western and central North Pacific (Semba et al. 2009), 11 years of age 
in the Northwest Atlantic (Natanson et al. 2006), and 15 years of age 
(217 cm fork length (FL)) in the western South Atlantic (Dono et al. 
2015). Females ultimately attain larger sizes than males, as has been 
documented in other shark species (Natanson et al. 2006). Maximum 
theoretical length in females is reported to be 370 cm TL in the 
western and central North Pacific (Semba et al. 2009) and 362 cm TL in 
the eastern North Pacific (Carreon-Zapiain et al. 2018). The maximum 
observed length for the species is 445 cm TL (Weigmann 2016), although 
Kabasakal and de Maddalena (2011) used photographs to estimate the 
length of a female caught off Turkey at 585 cm TL.
    Age and size at maturity vary by geographic location. In general, 
males

[[Page 68240]]

and females reach maturity at approximately 6-9 and 15-21 years 
(Natanson et al. 2006; Semba et al. 2009), and at sizes of 180-222 cm 
TL and 240-289 cm TL (Conde-Moreno and Galvan-Magana 2006; White 2007; 
Varghese et al. 2017), respectively. Additional information on growth 
and reproductive parameters for the species can be found in Table 1 of 
the Status Review Report.

Reproductive Biology

    Shortfin mako sharks reproduce through oophagous (meaning `egg 
eating') vivipary, wherein, after depletion of their yolk-sac, the 
embryos develop by ingesting unfertilized eggs inside the mother's 
uterus and are born as live young (Stevens 1983; Mollet et al. 2000). 
Estimates of gestation time vary from nine months to 25 months (Mollet 
et al. 2000; Duffy and Francis 2001; Joung and Hsu 2005; Semba et al. 
2011) and litter sizes typically range from four to 25 pups (Mollet et 
al. 2000; Joung and Hsu 2005; Semba et al. 2011). Several studies find 
that litter size increases with maternal size (Mollet et al. 2000; 
Semba et al. 2011), though others find no evidence of this relationship 
(Joung and Hsu 2005; Liu et al. 2020). Size at birth is approximately 
70 cm TL (Mollet et al. 2000). The reproductive cycle is estimated to 
take up to 3 years, with a potential resting period of 18 months 
(Mollet et al. 2000). There is evidence that parturition (birth) occurs 
in late winter to mid-spring in both the Northern and Southern 
Hemispheres based on embryonic growth estimates (Mollet et al. 2000; 
Semba et al. 2011; Bustamante and Bennett 2013), though Duffy and 
Francis (2001) found evidence of parturition in summer. With regard to 
mating strategy, two studies have found genetic evidence for polyandry 
and multiple paternity within litters, though other mating strategies 
(e.g., polygyny or monogamy) cannot be ruled out (Corrigan et al. 2015; 
Liu et al. 2020).

Population Structure and Genetics

    Although certain ocean currents and features may limit movement 
patterns between different regions as discussed previously (see Habitat 
Use), several genetic studies indicate a globally panmictic 
(characterized by random mating) population with some genetic 
structuring among ocean basins.
    Heist et al. (1996) investigated population structure using 
restriction fragment length polymorphism analysis of maternally 
inherited mitochondrial DNA (mtDNA) from shortfin mako sharks in the 
Northwest Atlantic (n = 21), central North Atlantic (n = 24), western 
South Atlantic (n = 23), eastern North Pacific (n = 30), and western 
South Pacific (n = 22). The North Atlantic samples showed significant 
isolation from other regions (p < 0.001) and differed from other 
regions by the relative lack of rare and unique haplotypes and high 
abundance of a single haplotype (Heist et al. 1996). Significant 
differences in haplotype frequencies were not detected between the 
samples from Brazil, Australia, and California (Heist et al. 1996). 
Haplotypes did not seem to be confined to specific regions, and the 
three most common haplotypes were found in all samples (Heist et al. 
1996). Clustering of mtDNA haplotypes did not initially support the 
presence of genetically distinct stocks of shortfin mako shark (Heist 
et al. 1996); however, reanalysis of the data found significant 
differentiation between the South Atlantic and North Pacific samples 
(Schrey and Heist 2003) in addition to isolation of the North Atlantic.
    A microsatellite analysis of samples from the North Atlantic (n = 
152), South Atlantic (Brazil; n = 20), North Pacific (n = 192), South 
Pacific (n = 43), and Atlantic and Indian coasts of South Africa (n = 
26) found very weak evidence of population structure (FST = 
0.0014, P = 0.1292; RST = 0.0029, P = 0.019) (Schrey and 
Heist 2003). Pairwise FST comparisons were not statistically 
significant after Bonferroni correction, though one pairwise 
RST value (North Atlantic vs. North Pacific) showed 
significant differentiation (RST = 0.0106, P = 0.0034). 
These results were insufficient to reject the null hypothesis of a 
single genetic stock of shortfin mako shark, suggesting that there is 
sufficient movement of shortfin mako sharks, and therefore gene flow, 
to reduce genetic differentiation between regions (Schrey and Heist 
2003). The authors note that their findings conflict with the 
significant genetic structure revealed through mtDNA analysis by Heist 
et al. (1996). They suggest that as mtDNA is maternally inherited and 
nuclear DNA is inherited from both parents, population structure shown 
by mtDNA data could indicate that female shortfin mako sharks exhibit 
limited dispersal and philopatry to parturition sites, while male 
dispersal allows for gene flow that would explain the results from the 
microsatellite data (Schrey and Heist 2003).
    Taguchi et al. (2011) analyzed mtDNA samples from the central North 
Pacific (n = 39), western South Pacific (n = 16), eastern South Pacific 
(n = 10), North Atlantic (n = 9), eastern Indian Ocean (n = 16), and 
western Indian Ocean (n = 16), finding evidence of significant 
differentiation between the North Atlantic, and the central North 
Pacific and eastern South Pacific (pairwise [Phi]ST = 0.2526 
and 0.3237, respectively). Interestingly, significant structure was 
found between the eastern Indian Ocean and the Pacific Ocean samples 
(pairwise [Phi]ST values for Central North Pacific, Western 
South Pacific, Eastern South Pacific are 0.2748, 0.1401, and 0.3721, 
respectively), but not between the eastern Indian and the North 
Atlantic (Taguchi et al. 2011).
    Corrigan et al. (2018) also found evidence of matrilineal structure 
from mtDNA data, while nuclear DNA data provide support for the 
existence of a globally panmictic population. Although there was no 
evidence of haplotype partitioning by region and most haplotypes were 
found across many (sometimes disparate) locations, Northern Hemisphere 
sampling locations were significantly differentiated from all other 
samples, suggesting reduced matrilineal gene flow across the equator 
(Corrigan et al. 2018). The only significant differentiation indicated 
by microsatellite data was between South Africa and southern Australia 
(pairwise FST = 0.037, [Phi]ST = 0.043) (Corrigan 
et al. 2018). Clustering analysis showed only minor differences in 
allele frequencies across regions and little evidence of population 
structure (Corrigan et al. 2018). Overall, the authors conclude that 
although spatial partitioning exists, the shortfin mako shark is 
genetically homogenous at a large geographic scale. Taken together, 
results of genetic analyses suggest that female shortfin mako sharks 
exhibit fidelity to ocean basins, possibly to utilize familiar pupping 
and rearing grounds, while males move across the world's oceans and 
mate with females from various basins, thereby homogenizing genetic 
variability (Heist et al. 1996; Schrey and Heist 2003; Taguchi et al. 
2011; Corrigan et al. 2018).
    Haplotype diversity in shortfin mako sharks has been found to be 
high in several studies. Heist et al. (1996) found 25 haplotypes among 
120 individuals for an overall haplotype diversity of 0.755 and a 
nucleotide diversity of 0.347. Taguchi et al. (2011) found haplotype 
and nucleotide diversity to be 0.92 and 0.0070, respectively, across 
the global range of the species. Corrigan et al. (2018) detected 48 
unique haplotypes among 365 individuals for a haplotype diversity of 
0.894  0.013 and found very low nucleotide diversity of 
0.004  0.003.

[[Page 68241]]

Demography

    Natural mortality for shortfin mako sharks is low and was estimated 
by Bishop et al. (2006) at 0.14 and 0.15 year-\1\ for males 
and females, respectively. Chang and Liu (2009) calculated natural 
mortality at 0.077-0.244 year-\1\ for females and 0.091-
0.203 year-\1\ for males in the Northwest Pacific. In the 
North Atlantic, natural mortality was estimated at 0.101 
year-\1\ (Bowlby et al. 2021). The generation time is 
estimated at 25 years (Cort[eacute]s et al. 2015; Rigby et al. 2019).
    In an analysis of productivity and susceptibility to longline 
fisheries in the Indian Ocean, Murua et al. (2018) calculated a 
population finite growth rate ([lambda]) for shortfin mako sharks of 
1.049 year-\1\ (1.036-1.061; Murua et al. 2018). Liu et al. 
(2015) estimated values for [lambda] of shortfin mako sharks off 
California to be 1.1213  0.0635 year-\1\ and 
1.0300  0.0763 year-\1\ for those in the 
Northwest Pacific. As the species displays sexual dimorphism in size, 
growth rates, and size at maturity, Tsai et al. (2015) argue that the 
use of a two-sex demographic model more accurately estimates the 
probability of decline risk and, therefore, better informs management 
decisions. Further, as the mating mechanism of shortfin mako sharks 
affects the proportion of breeding females and has not been 
conclusively established, these scenarios (monogamous, polyandrous, 
polygynous) should be modeled as well (Tsai et al. 2015). The authors 
report that in the Northwest Pacific, without fisheries-related 
mortality, values for [lambda] were 1.047, 1.010, and 1.075 
year-\1\ for females and 1.056, 1.011, and 1.090 
year-\1\ for males in monogamous, polyandrous, and 
polygynous mating scenarios, respectively. Under fishing conditions at 
the time of the study, all values for [lambda] dropped to less than one 
(0.943, 0.930, and 0.955 year-\1\ for females and 0.918, 
0.892, and 0.939 year-\1\ for males in monogamous, 
polyandrous, and polygynous mating scenarios, respectively). Thus, 
population declines were expected regardless of the mating system 
modeled.
    Productivity for the shortfin mako shark is quite low. In a recent 
analysis using six methods, Cort[eacute]s (2016) determined that the 
intrinsic rate of population increase (rmax) for Atlantic 
shortfin mako sharks ranged from 0.036-0.134 yr-\1\. These 
values were among the lowest calculated from 65 populations and species 
of sharks (Cort[eacute]s 2016).

Abundance and Trends

    Currently, there is no estimate of the absolute global abundance of 
the shortfin mako shark; however, based on the age-structured 
assessments conducted by ICCAT (2017) and the ISC Shark Working Group 
(2018), current abundance is estimated to be one million individuals in 
the North Atlantic and eight million individuals in the North Pacific 
(FAO 2019). Comprehensive analyses based on available regional stock 
assessments and standardized catch-per-unit-effort (CPUE) data have 
been used by the International Union for Conservation of Nature (IUCN) 
to approximate trends for the species globally.
    In the 2019 IUCN Red List assessment, Rigby et al. estimated a 
global population trend using the following data sources: (1) the 2017 
stock assessments conducted by ICCAT for the North and South Atlantic, 
(2) the 2018 stock assessment conducted by the ISC Shark Working Group 
for the North Pacific, (3) standardized CPUE data for the South Pacific 
from Francis et al. (2014), and (4) a preliminary stock assessment in 
the Indian Ocean by Brunel et al. (2018). Individual trends by region 
are discussed below. Using Just Another Red List Assessment (JARA) 
(Winker et al. 2018; Sherley et al. 2019), a Bayesian state-space tool 
for trend analysis of abundance indices, Rigby et al. (2019) found that 
the species is declining in all oceans other than the South Pacific, 
where it is increasing, with the steepest population declines indicated 
in the North and South Atlantic. Due to the unreliable stock assessment 
in the South Atlantic (discussed further below), Rigby et al. (2019) 
considered the North Atlantic stock assessment to be representative of 
the South Atlantic for the trend analysis. However, this may have 
inaccurately represented the extent of decline in the South Atlantic; 
the North Atlantic has experienced the largest known degree of decline 
across the species' range, and while there is some possibility that the 
South Atlantic has a similar stock status, the 2017 stock assessment 
does not support that conclusion, and accordingly, ICCAT has not taken 
comparable regulatory action for the species in the South Atlantic. A 
global trend was estimated by weighting each region's trend by the 
relative size of each region. To standardize the time period over which 
the trends were calculated, JARA projected forward the amount of years 
without observations that it would take to reach three generation 
lengths. The overall median population reduction was estimated at 46.6 
percent, with the highest probability of 50-79 percent reduction over 
three generation lengths (72-75 years). Because available datasets for 
each region cover different time periods and have different durations, 
the timeframe of this trend is not a comparison between two specific 
years, but rather a standardized timeframe of three generation lengths. 
Trends indicated by Rigby et al. (2019) do not always align with 
abundance and trend indicators from other sources, as discussed below. 
The JARA framework used by Rigby et al. (2019) has been described as 
inappropriate for this long-lived, sexually dimorphic species because 
it only uses mean annual trends in the population over the assessment 
period and does not consider size or age structures of the population 
over recent decades (Kai 2021a). Available information on abundance and 
trends by region is discussed below. Stock assessments provide 
information on the status of a stock, with results presented using the 
terms ``overfished'' and ``overfishing.'' Specific to the context of 
the Magnuson-Stevens Fishery Conservation and Management Act (MSA), a 
stock or stock complex is considered ``overfished'' when its biomass 
has declined below minimum stock size threshold (MSST), defined as the 
level of biomass below which the capacity of the stock or stock complex 
to produce maximum sustainable yield (MSY) on a continuing basis has 
been jeopardized (50 CFR 600.310(e)(2)(E)-(F)). Overfishing occurs 
whenever a stock or stock complex is subjected to a level of fishing 
mortality or total catch that jeopardizes the capacity of a stock or 
stock complex to produce MSY on a continuing basis (50 CFR 
600.310(e)(2)(B)). While the stock assessments referenced in this 
finding do not define ``overfished'' and ``overfishing'' using the 
exact language above, they use the two terms with equivalent meanings. 
It is important to note that the terms ``overfished'' and 
``overfishing'' do not have any specific relationship to the terms 
``threatened'' or ``endangered'' as defined in the ESA. While a stock 
that is overfished is not able to sustain an exploitive fishery at MSY 
(i.e., the highest possible annual catch that can be sustained over 
time), there is a significant difference between a stock that is 
overfished and a stock that is in danger of extinction. A stock will 
become overfished long before it is threatened with extinction, and can 
be stable at biomass levels that do not support MSY. Similarly, one 
goal of the MSA (and fisheries management organizations) is to 
``rebuild'' overfished

[[Page 68242]]

stocks to biomass levels that will support MSY. This level can be 
significantly above the biomass levels necessary to ensure that a 
species is not in danger of extinction. Thus, evidence of declining 
abundance that threatens the ability of the fishery to provide MSY are 
relevant, but not dispositive of a threatened or endangered species 
determination. Therefore, while available information about whether 
specific stocks are overfished or experiencing overfishing is relevant 
to and considered in our ESA extinction risk analysis, the fact that a 
stock may be considered ``overfished'' or experiencing ``overfishing'' 
does not automatically indicate that any particular status is 
appropriate under the ESA. Stock assessments, which provide information 
for determining the sustainability of a fishery, are based on different 
criteria than status reviews conducted under the ESA, which provide 
information to assess the likelihood of extinction of the species. When 
conducting a status review under the ESA, we use relevant information 
from available stock assessments, such as levels of biomass and fishing 
mortality, and apply the ESA's definitions of threatened and endangered 
species to the information in the record using our standard tools of 
ESA extinction risk analysis. As part of our ESA extinction risk 
analysis, when examining whether overutilization for commercial 
purposes is a threat to the species, we consider whether the species 
has been or is being harvested at levels that contribute to or pose a 
risk of extinction to the species.
North Atlantic Ocean
    The most recent stock assessment by ICCAT indicates a combined 90 
percent probability that the North Atlantic stock is in an overfished 
state and is experiencing overfishing (ICCAT 2017). The nine model runs 
used in this assessment generally agreed, indicating that stock 
abundance in 2015 was below biomass at maximum sustainable yield 
(BMSY) (ICCAT 2017). The age-structured stock assessment 
model estimates historical declines in spawning stock fecundity (SSF, 
defined as the number of pups produced in each year) from 1950 
(unfished condition) to 2015 at 50 percent and recent declines (from 
2006 to 2015) at 32 percent (FAO 2019). All assessment models were 
consistent, and together indicated that the North Atlantic shortfin 
mako shark has experienced historical declines in total biomass of 
between 47-60 percent, and recent declines in total biomass of between 
23-32 percent (FAO 2019). Projections conducted in the 2017 assessment 
using a production model estimated that for a total allowable catch 
(TAC; in this case, TAC refers to all sources of mortality and is not 
limited to landings data) of 1,000 metric tons (t), the probability of 
the stock being rebuilt and not experiencing overfishing (biomass (B) > 
B MSY, and fishing mortality (F) < fishing mortality at MSY 
(FMSY)) was only 25 percent by 2040 (one generation length).
    In 2019, the ICCAT Standing Committee on Research and Statistics 
(SCRS) carried out new projections for North Atlantic shortfin mako 
shark through 2070 (two generation lengths) using an integrated model 
(Stock Synthesis) at the Commission's request. The 2019 update to the 
stock assessment projects that even with a zero TAC, the North Atlantic 
stock would have a 53 percent probability of being rebuilt (SSF > 
SSFMSY) and not experiencing overfishing (F < 
FMSY) by 2045, and that regardless of TAC (including a TAC 
of 0 t), the stock will continue declining until 2035 (ICCAT 2019). 
Projections showed that a TAC of 500 t has a 52 percent probability of 
rebuilding the stock, with overfishing not occurring, by 2070. The 
projections indicated that realized TAC must be 300 t or less to ensure 
that the stock will be rebuilt and not experiencing overfishing with at 
least a 60 percent probability by 2070 (ICCAT 2019). These TAC options 
with associated time frames and probabilities of rebuilding were 
presented to the Commission; however, given the vulnerable biological 
characteristics of this stock and these pessimistic projections, to 
accelerate the rate of recovery and to increase the probability of 
success, the SCRS recommended that the Commission adopt a non-retention 
policy without exception.
    The 2017 stock assessment and 2019 update to the stock assessment 
present more accurate and rigorous results than the prior 2012 
assessment. The 2012 assessment overestimated stock size, 
underestimated fishing mortality, and suggested a low probability of 
overfishing (ICCAT 2019). Input data and model structure changed 
significantly between the 2012 and 2017 ICCAT stock assessments: catch 
time series start earlier (1950 vs. 1971 in the 2012 assessment), some 
biological inputs have changed and are sex-specific in the 2017 
assessment, and additional length composition data became available 
(ICCAT 2017). In addition, the CPUE series have been decreasing since 
2010, which was the last year in the 2012 assessment models (ICCAT 
2017). Finally, the age-structured model in the 2017 stock assessment 
more accurately captured the time-lags in population dynamics of a 
long-lived species than the production models used in 2012.
    The IUCN's JARA trend analysis for the North Atlantic region relied 
on the 2017 ICCAT stock assessment. Trend analysis of modeled biomass 
estimated a median decline of 60 percent in the North Atlantic based on 
annual rates of decline of 1.2 percent between 1950 and 2017 (Rigby et 
al. 2019), which is consistent with the decrease in total biomass (60 
percent) obtained from Stock Synthesis model run 3 from the 2017 ICCAT 
stock assessment.
    There is no stock assessment available for shortfin mako sharks in 
the Mediterranean Sea. Ferretti et al. (2008) compiled data from public 
and private archives representing sightings, commercial fisheries, and 
recreational fisheries data in the western Mediterranean Sea and used 
generalized linear models to conduct a meta-analysis of encounter 
trends. Long-term combined trends for shortfin mako shark and porbeagle 
(Lamna nasus) in the Mediterranean Sea indicate up to a 99.99 percent 
decrease in abundance and biomass since the early 19th century, though 
there was considerable variability among datasets due to geography and 
sample size (Ferretti et al. 2008). While shortfin mako sharks spanning 
a broad range of sizes (suggesting breeding/pupping in the region) are 
occasionally reported as bycatch in swordfish and albacore longline 
fisheries (Megalofonou et al. 2005), or in other artisanal or 
commercial fisheries (Kabasakal 2015), from the eastern Mediterranean 
Sea, no reliable estimates of abundance are available for this region.
    Overall, the best available scientific and commercial information 
indicates that the North Atlantic shortfin mako shark population has 
experienced historical declines in biomass of between 47 and 60 
percent, and declines will continue until at least 2035 regardless of 
fishing mortality.
South Atlantic Ocean
    Results of the most recent ICCAT stock assessment for shortfin mako 
sharks in the South Atlantic indicate a high degree of uncertainty 
(ICCAT 2017). One model (Just Another Gibbs Sampler emulating the 
Bayesian production model) estimated that the stock was not overfished 
(B2015/BMSY = 1.69-1.75) but that overfishing may 
be occurring (F2015/FMSY = 0.86-1.07). Two runs 
from this model indicate a 0.3-1.4 percent probability of the stock 
being overfished and overfishing occurring, and a 29-47.4 percent 
probability of the stock not being overfished but

[[Page 68243]]

overfishing occurring, or, alternatively, the stock being overfished 
but overfishing not occurring, and a 52.3-69.6 percent probability of 
the stock not being overfished and overfishing not occurring (ICCAT 
2017). The Just Another Bayesian Biomass Assessment (JABBA) model 
results indicated an implausible stock trajectory and were, therefore, 
not relied upon for management advice. The Catch-only Monte-Carlo 
method (CMSY) model estimates indicate that the stock could be 
overfished (B2015/BMSY = 0.65 to 1.12) and that 
overfishing is likely occurring (F2015/FMSY = 
1.02 to 3.67). Considering catch scenarios C1 (catches starting in 1950 
in the north and 1971 in the south, as reported in the March 2017 ICCAT 
shortfin mako data preparatory meeting) and C2 (alternative estimated 
catch series based on ratios (method described by Coelho and Rosa 
2017), starting in 1971), Catch-only Monte-Carlo method model estimates 
indicated a 23-89 percent probability of the stock being overfished and 
overfishing occurring, a 11-48 percent probability of the stock not 
being overfished but overfishing occurring, or alternatively, the stock 
being overfished but overfishing not occurring, and only a 0-29 percent 
probability of the stock not being overfished and overfishing not 
occurring. Generally, while CPUE exhibited an increasing trend over the 
last 15 years, both catches and effort increased contrary to the 
expectation that the population is expected to decline with increasing 
catch (FAO 2019). This inconsistency caused the ICCAT working group to 
consider the assessment highly uncertain, and they conducted no 
projections for the South Atlantic stock. Nevertheless, the combined 
assessment models found a 19 percent probability that the stock is 
overfished and is experiencing overfishing, a 48 percent probability of 
the stock not being overfished but overfishing occurring, or 
alternatively, the stock being overfished but overfishing not 
occurring, and a 36 percent probability that the stock is not being 
overfished or experiencing overfishing (ICCAT 2017). The assessment 
also notes that, despite uncertainty, in recent years the stock may 
have been at, or is already below, BMSY, and fishing 
mortality is already exceeding FMSY. Based on the 
uncertainty of the stock status, combined with the species' low 
productivity, the ICCAT working group concluded that catches should not 
increase above average catch for the previous 5 years, about 2,900 t 
(ICCAT 2017; FAO 2019). There is a significant risk that the South 
Atlantic stock could follow a trend similar to that of the North 
Atlantic stock given that fishery development in the South Atlantic 
predictably follows that in the North, and that the biological 
characteristics of the stock are similar. The 2019 update to the stock 
assessment (ICCAT 2019) therefore reiterates the recommendation that, 
at a minimum, catch levels should not exceed the minimum catch in the 
last 5 years of the assessment (2,001 t with catch scenario C1).
    In addition to the ICCAT stock assessment, standardized catch rates 
in South Atlantic longlines indicate steep declines in the average CPUE 
of shortfin mako shark between 1979-1997 and 2007-2012 (Barreto et al. 
2016). However, the methodologies used in this study have several 
caveats and limitations, including the standardization analysis being 
applied individually to each of the time series and the use of 
different variables. Therefore, the results are not directly comparable 
between the different time periods and cannot be used to infer the 
total extent of decline over the entirety of the time series (FAO 
2019).
    Overall, despite high uncertainty in abundance and trends for the 
species in this region, the best available scientific and commercial 
data indicate that there is a 19 percent probability that the 
population is overfished and is experiencing overfishing, and in recent 
years the stock may have been at, or is already below, BMSY 
and fishing mortality is already exceeding FMSY.
North Pacific Ocean
    The most comprehensive information on trends for shortfin mako 
sharks in the North Pacific comes from the 2018 ISC Shark Working Group 
stock assessment, which found that the North Pacific stock was likely 
not in an overfished condition and was likely not experiencing 
overfishing between 1975 and 2016 (42 years) (ISC Shark Working Group 
2018). This analysis used a Stock Synthesis model that incorporated 
size- and age-specific biological parameters and utilized annual catch 
data from 18 fleets between 1975 and 2016, annual abundance indices 
from five fleets for the same period, and annual size composition data 
from 11 fleets between 1994 and 2016 (Kai 2021a). This assessment 
determined that the abundance of mature females was 860,200 in 2016, 
which was estimated to be 36 percent higher than the number of mature 
females at maximum sustainable yield (MSY) (ISC Shark Working Group 
2018). Future projections indicated that spawning abundances were 
expected to increase gradually over a 10-year period (2017-2026) if 
fishing mortality remains constant or is moderately decreased relative 
to 2013-2015 levels (ISC Shark Working Group 2018). Using results from 
the ISC stock assessment, historical decline in abundance (1975-1985 to 
2006-2016) is estimated at 16.4 percent, and a recent increase (2006-
2016) is estimated at 1.8 percent (CITES 2019).
    The IUCN Red List Assessment for global shortfin mako shark also 
used the ISC assessment to model the average trend in the North Pacific 
stock over three generation lengths (72 years) and indicated a median 
decline of 36.5 percent based on annual rates of decline of 0.6 percent 
from 1975-2016 (Rigby et al. 2019). A comprehensive comparison of the 
assessments by the ISC and the IUCN (Kai 2021a) describes JARA (applied 
by Rigby et al. 2019) as a useful tool in extinction risk assessments 
for data-poor pelagic sharks, but inappropriate for the relatively 
data-rich North Pacific shortfin mako shark. The assessment by IUCN 
used only the mean annual trends in the population over the assessment 
period estimated from Stock Synthesis, and did not consider size or age 
structure of the population over recent decades. Kai (2021a) concludes 
that the results of the ISC's assessment of current and future status 
of North Pacific shortfin mako shark are more robust and reliable than 
those of the IUCN, and finds a median decline of the population 
trajectory of 12.1 percent over three generation lengths with low 
uncertainty.
    The ISC Shark Working Group's 2021 indicator-based analysis for 
shortfin mako sharks in the North Pacific used time series of catch, 
indices of relative abundance (CPUE), and length-frequency data from 
multiple fisheries over the time period 1957-2019 to monitor for 
potential changes in stock abundance since the 2018 benchmark 
assessment. Catch of shortfin mako shark in 2019 was the second highest 
value for the last decade, and the scaled CPUEs indicated a stable and 
slightly increasing trend in the four major fleets (U.S. Hawaii 
longline shallow-set, Taiwan longline large-scale, Japan research and 
training vessels, and Mexico observer for longline) (ISC Shark Working 
Group 2021). The Working Group concluded that there were no signs of 
major shifts in the tracked indicators that would suggest a revision to 
the current stock assessment schedule for shortfin mako shark is 
necessary (ISC Shark Working Group 2021). The next stock assessment is 
scheduled for 2024.

[[Page 68244]]

    Observer data from the Western and Central Pacific Fisheries 
Commission (WCPFC) indicate that longline catch rates of mako sharks in 
the North Pacific declined significantly by an average of 7 percent (95 
percent confidence interval (CI): 3-11 percent) annually between 1995 
and 2010 (Clarke et al. 2013). However, these data represent trends for 
both longfin and shortfin mako sharks combined, and the performance of 
the standardization model was poorer than for other studied shark 
species, making the estimated trend less reliable. There were also 
variable size trends for mako sharks in the North Pacific, with females 
showing significant increases in median length in one region (Clarke et 
al. 2013). In an updated indicator analysis using the same data, Rice 
et al. (2015) noted that the standardized CPUE trend looked relatively 
stable between 2000 and 2010, but no inference was possible for the 
last 4 years (2010-2014) due to data deficiencies in some years.
    Kai et al. (2017) analyzed catch rates in the Japanese shallow-set 
longline fishery in the western and central North Pacific from 2006-
2014, finding an increasing trend since 2008. However, fishery-
independent logbook data collected from Japanese research and training 
vessels in the western and central North Pacific (mainly 0-40[deg] N 
and 130[deg] E-140[deg] W) from 1992-2016 showed a decreasing catch 
rate since 2008 (Kai 2019). The opposing trends indicated by fishery-
dependent and -independent data in this region may be due to factors 
such as differing areas of operation, differing gear types, 
underreporting by both data sources, and differing model structures 
applied to the data (Kai 2019). Additionally, standardized CPUE 
estimates from 2011-2019 in the Japanese longline fleet operating in 
the North Pacific Ocean showed a stable trend from 2011 to 2016, with a 
slight decline after 2016 (Kanaiwa et al. 2021). The authors note that 
observer coverage in the fleet is low (1.7-3.0 percent in certain 
areas) and that these results may not represent the overall trend for 
the North Pacific stock of shortfin mako shark (Kanaiwa et al. 2021).
    Results from stock assessments and standardized CPUE trends from 
observer data are more comprehensive, robust, and reliable than trends 
from fishery logbook data. Therefore, we find that the best scientific 
and commercial information available indicates that shortfin mako 
sharks in the North Pacific are neither overfished nor experiencing 
overfishing, and the population is likely stable and potentially 
increasing despite evidence of historical decline and indications of 
recent decline in fishery-independent datasets.
South Pacific Ocean
    In the South Pacific, longline catch rates reported to WCPFC did 
not indicate a significant trend in abundance of mako shark (shortfin 
and longfin combined) between 1995 and 2010 (Clarke et al. 2013). In an 
updated indicator analysis, standardized CPUEs for the mako shark 
complex show a relatively stable trend in relative abundance, with low 
points in 2002 and 2014, though the 2014 point is based on relatively 
few data and should be interpreted with caution (Rice et al. 2015). In 
New Zealand waters, logbook and observer data from 1995-2013 analyzed 
by Francis et al. (2014) indicate that shortfin mako sharks were not 
declining, and may have been increasing, over the period from 2005-
2013. More recently, an analysis of the data did not result in 
statistically significant trend fits for two of the data series; those 
that were significant were increasing (Japanese South 2006-2015, 
Domestic North 2006-2013, and Observer Data 2004-2013) (FAO 2019). 
Trend analysis of modeled biomass indicates a median increase of 35.2 
percent over three generation lengths based on estimated annual rates 
of increase of 0.5 percent from 1995-2013 (Rigby et al. 2019). In sum, 
the best scientific and commercial information available indicates that 
shortfin mako sharks in the South Pacific have an increasing population 
trend.
Indian Ocean
    Only preliminary stock assessments using data-limited assessment 
methods have been conducted for the shortfin mako shark in the Indian 
Ocean, with few other stock indicators available. Catch data are 
thought to be incomplete for several reasons: landings do not reflect 
the number of individuals finned and discarded at sea, shortfin mako 
sharks are not sufficiently specified in catch data and are often 
aggregated with other species, shortfin mako shark may be misidentified 
as longfin mako shark, and recorded weight may often refer to processed 
weight rather than live weight (Bonhommeau et al. 2020). These factors 
were a significant consideration in our evaluation of the species. With 
these caveats in mind, a preliminary assessment by Brunel et al. (2018) 
was carried out based on CPUE estimates from Portuguese (2000-2016) and 
Spanish (2006-2016) swordfish and tuna longline fleets operating in the 
Indian Ocean Tuna Commission (IOTC) Convention area. Results from two 
models (a Bayesian Schaefer-type production model and another model 
analyzing the trends of catches) indicate that the stock is 
experiencing overfishing (F2015/FMSY = 2.57), but 
is not yet overfished (B2015/BMSY close to one) 
(Brunel et al. 2018). However, there were considerable uncertainties in 
the estimates and conflicting trends in biomass between the two models 
used. Nonetheless, trajectories showed consistent trends toward both 
overfished and subject to overfishing status (Brunel et al. 2018). 
Using the results of the Schaefer model from Brunel et al. (2018), 
historical decline (1970-1980 to 2005-2015) was estimated at 26 
percent, recent decline (2005 to 2015) was estimated at 18.8 percent, 
and future 10-year decline was projected at 41.6 percent from the 
historical baseline (1970-1980 to 2015-2025) (CITES 2019). A trend 
analysis for modeled biomass in the Indian Ocean using Brunel et al.'s 
assessment indicates a median decline of 47.9 percent over three 
generation lengths based on annual rates of decline of 0.9 percent from 
1971-2015 (Rigby et al. 2019).
    A more recent preliminary assessment using updated catch and CPUE 
indices also indicates that the shortfin mako shark in the Indian Ocean 
is experiencing overfishing but is not overfished (Bonhommeau et al. 
2020). This assessment uses nominal catch of shortfin mako shark as 
reported to the IOTC (1964-2018) and scaled CPUEs from Japan (1993-
2018), Spain (2001-2018), Taiwan (2005-2018), and Portugal (2000-2018). 
Bonhommeau et al. (2020) used JABBA and CMSY models, both of which gave 
results that were generally consistent with the previous assessment: 
that the stock is currently undergoing overfishing and is not 
overfished.
    In a separate study, Wu et al. (2021) analyzed standardized CPUE 
trends using observer records and logbook data from 2005-2018 for the 
Taiwanese longline fishery in the Indian Ocean, which was the second 
largest shortfin mako shark-catching nation in the region in 2019. The 
standardized CPUEs indicate a gradual decrease between 2005 and 2007, 
followed by a sharp increase in 2008, a slow decline between 2008 and 
2015, and another increase between 2015 and 2018 (Wu et al. 2021). 
However, Wu et al. (2021) note that the rapid increases in CPUEs 
between 2007 and 2008 and later between 2015 and 2017 may be 
unrealistic for the stock biomass of such a long-lived species, and 
suggest that the results may be due to increased reporting by skippers 
and observers.

[[Page 68245]]

Logbook data from Japanese longliners operating in the Indian Ocean 
from 1993-2018 indicate that abundance of shortfin mako shark decreased 
from 1993-2009, and increased slightly since then (Kai and Semba 2019). 
Standardized CPUE has risen after 2008 in Portuguese and Spanish 
longline fleets as well (Coelho et al. 2020; Ramos-Cartelle et al. 
2020), although these data sets were included in the preliminary stock 
assessment conducted by Bonhommeau et al. (2020). In the Arabian Sea 
CPUE data suggest variable abundance and little evidence of significant 
population reduction (Jabado et al. 2017). Fishing pressure in this 
region is high, and because the species has high susceptibility to 
pelagic fisheries, Jabado et al. (2017) estimated that over the past 3 
generations the population has declined 20-30 percent, with future 
declines expected over the next 3 generations. Results from these 
studies may reflect partial stock status in the Indian Ocean, but may 
not have sufficient spatial coverage to be indicative of the entire 
stock status.
    In sum, the best available scientific and commercial information 
indicates that shortfin mako shark population in the Indian Ocean is 
experiencing overfishing but is not yet overfished, and recent 
increasing CPUE trends are indicated in Spanish, Portuguese, and 
Taiwanese longline fleets. Catch data have the potential to be 
substantially underestimated and the recent increases in CPUE from 
these fleets may not reflect trends in abundance.
Summary
    Overall, while abundance estimates for the shortfin mako shark are 
not available for all regions, the stock assessments available for the 
North Atlantic and North Pacific Oceans indicate current numbers of 
about one million and eight million individuals, respectively (FAO 
2019). These estimates were generated by the FAO Expert Advisory Panel, 
which extracted these numbers using the age-structured assessments 
conducted by ICCAT (2017) and the ICS Shark Working Group (2018). Rigby 
et al. (2019) conducted a trend analysis of shortfin mako shark 
abundance indices using the 2017 ICCAT stock assessment in the 
Atlantic, the 2018 ISC Shark Working Group stock assessment in the 
North Pacific, a preliminary stock assessment for the Indian Ocean 
(Brunel et al. 2018), and a CPUE indicator analysis from New Zealand 
for the South Pacific (Francis et al. 2014). Due to the unreliable 
stock assessment in the South Atlantic, Rigby et al. (2019) considered 
the North Atlantic stock assessment to be representative of the South 
Atlantic for the trend analysis. However, this may have inaccurately 
represented the extent of decline in the South Atlantic for reasons 
described above. This assessment estimates the overall median 
population reduction for the global shortfin mako shark population at 
46.6 percent, with the highest probability of 50-79 percent reduction 
over three generation lengths (72-75 years) (Rigby et al. 2019), 
although the JARA framework used by Rigby et al. has been described as 
inappropriate for this species as it only uses mean annual trends in 
the population over the assessment period and does not consider size or 
age structure of the population over recent decades (Kai 2021a).
    Population decline has been indicated in the North Atlantic with 
high certainty, and abundance is likely to continue declining until at 
least 2035 even in the absence of fishing mortality (ICCAT 2019). In 
the North Pacific, while there is evidence of historical decline, 
recent assessments indicate that the stock is neither overfished nor 
experiencing overfishing, and the population is likely stable or 
potentially increasing (ISC Shark Working Group 2018). Although a stock 
assessment has not been completed for shortfin mako sharks in the South 
Pacific, the best available scientific and commercial data and analyses 
indicate an increasing population trend (Francis et al. 2014; Rigby et 
al. 2019). Abundance of the shortfin mako shark in the South Atlantic 
and Indian Oceans is not as clear, given significant uncertainties in 
the data available from these regions. The most recent stock 
assessments of shortfin mako sharks in the South Atlantic has a high 
degree of uncertainty, and indicate a combined 19 percent probability 
that the stock is overfished and experiencing overfishing (ICCAT 2017). 
Preliminary assessments in the Indian Ocean indicate that the 
population is experiencing overfishing but is not yet overfished 
(Brunel et al. 2018; Bonhommeau et al. 2020).

Extinction Risk Analysis

    In evaluating the level of risk faced by a species and deciding 
whether the species is threatened or endangered, we must consider all 
relevant data and are required under the ESA to base our conclusions on 
the best scientific and commercial data available. In evaluating and 
interpreting the best available data we also apply professional 
judgment. We evaluate both the viability of the species based on its 
demographic characteristics (abundance, productivity, spatial 
distribution, and diversity; see McElhany et al. (2000)), and the 
threats to the species as specified in ESA section 4(a)(1)(A)-(E).

Methods

    This section discusses the methods used to evaluate threats and the 
overall extinction risk to the shortfin mako shark. For purposes of the 
risk assessment, an ERA Team comprising biologists and shark experts 
was convened to review the best available information on the species 
and evaluate the overall risk of extinction facing the shortfin mako 
shark, now and in the foreseeable future.
    According to regulations implementing section 4 of the ESA that 
were in place during the ERA Team's deliberations, which was consistent 
with our practice since 2009 in accordance with a legal opinion of the 
Solicitor of the United States Department of the Interior, ``The 
Meaning of `Foreseeable Future' in section 3(20) of the Endangered 
Species Act'' (M-37021, Jan. 16, 2009; referred to herein as ``the 2009 
M-Opinion''), the foreseeable future extends only so far into the 
future as we can reasonably determine that both the future threats and 
the species' responses to those threats are likely. See 50 CFR 
424.11(d). Under our longstanding practice we describe the foreseeable 
future on a case-by-case basis, using the best available data and 
taking into account considerations such as the species' life-history 
characteristics, threat-projection timeframes, and environmental 
variability. In addition, because a species may be susceptible to a 
variety of threats for which different data are available, or which 
operate across different time scales, the foreseeable future may not 
necessarily be reducible to a particular number of years and may not be 
defined the same way for each threat. Although the regulations were 
vacated and remanded without a decision on the merits on July 5, 2022, 
by the United States District Court for the Northern District of 
California, and that order has been temporarily stayed as of September 
21, 2022, whether or not those regulations remain in place does not 
affect our understanding or application of the ``foreseeable future.'' 
The 2019 regulations merely codified the approach of our longstanding 
interpretation of this term in use prior to the issuance of these 
regulations (see 84 FR 45020, August 27, 2019), and the court did not 
make any findings on the merits that would call this approach into 
question. Thus, with or without the 2019 regulations, we would continue 
to apply an approach to the foreseeable future rooted in the 2009 M-
Opinion.

[[Page 68246]]

    In determining an appropriate foreseeable future timeframe for the 
shortfin mako shark, the ERA Team first considered the species' life 
history. The species matures late in life, with females estimated to 
mature at an age of 15-21 years and males at 6-9 years of age (Bishop 
et al. 2006; Natanson et al. 2006; Semba et al. 2009; Groeneveld et al. 
2014). The species has high longevity of at least 28-32 years (Bishop 
et al. 2006; Natanson et al. 2006) and exhibits relatively slow growth 
rates and low productivity (Cort[eacute]s et al. 2015). The ERA Team 
also considered generation time for the shortfin mako shark, which is 
defined as the average interval between the birth of an individual and 
the birth of its offspring, and has been estimated at 25 years 
(Cort[eacute]s et al. 2015). Given the life history characteristics of 
the shortfin mako shark, the ERA Team concluded that it would likely 
take several decades for any conservation management actions to be 
realized and reflected in population abundance indices.
    As the main threats to the species are overutilization in 
commercial fisheries and the inadequacy of regulatory measures that 
manage these fisheries (see Summary and Analysis of Section 4(a)(1) 
Factors below), the ERA Team then considered the time period over which 
they could reasonably predict the likely impact of these threats on the 
biological status of the species. The ERA Team took available 
projections for shortfin mako shark abundance into consideration: the 
2019 ICCAT update to the stock assessment for the North Atlantic 
carried out projections over 2 generation lengths, or 50 years; the ISC 
Shark Working Group's 2018 stock assessment for North Pacific shortfin 
mako sharks used 10-year projections; and the IUCN Red List Assessment 
carried out projections based on available data to achieve a 3 
generation length time frame using JARA.
    In examining these projections and their respective confidence 
intervals, the ERA Team noted that uncertainty increased substantially 
after about one generation length in all cases across multiple regions 
of the species' range. The ERA Team noted that in the IUCN JARA 
projections conducted for shortfin mako sharks by region, uncertainty 
(i.e., the difference between the median and confidence intervals) 
increased to 50 percent by 2030 for the South Pacific population (about 
18 years projected), and 40 percent by 2040 for the Indian and North 
Pacific populations (about 25 years projected). Additionally, the ERA 
Team noted that ICCAT's report of the 2019 shortfin mako shark stock 
assessment update meeting emphasizes that the Kobe II Strategy Matrix 
(K2SM) used to provide scientific advice for the North Atlantic stock 
does not capture all uncertainties associated with the fishery and the 
species' biology. Specifically, ICCAT's SCRS stated that ``the length 
of the projection period (50 years) requested by the Commission 
significantly increases the uncertainty of the results. Therefore, the 
Group advised that the results of the K2SM should be interpreted with 
caution,'' (ICCAT 2019). As a result of this statement, the ERA Team 
considered the 50-year projection to have questionable scientific 
merit, with estimates over that time frame only provided because the 
Commission requested them. Given the concerns about uncertainty that 
were repeatedly highlighted by the SCRS (ICCAT 2019), the ERA Team 
concluded that the 50-year period was not an appropriate time period 
for the foreseeable future.
    In addition to uncertainty in projected abundance trends, the ERA 
Team discussed the uncertainty associated with future management 
measures and fishing behavior across regions. ICCAT is currently the 
only major Regional Fishery Management Organization (RFMO) with 
management measures specific to shortfin mako sharks, and recently 
adopted a two-year retention ban for the species in the North Atlantic. 
The conservation benefit of this measure is uncertain, however, as it 
does not require fishermen to modify gear or fishing behavior that 
would reduce at-vessel or post-release mortality of the species. 
Further, management of the species after this two-year ban expires is 
unknown. Some of the top shortfin mako shark-catching nations in this 
region (Spain, Portugal, and Morocco) have very recently announced 
unilateral retention prohibitions for North Atlantic shortfin mako 
shark, although the effect these bans will have on the species is again 
unknown, even if they ultimately are well implemented. Although 
projections carried out in 2019 by ICCAT's SCRS indicate that the North 
Atlantic stock will continue declining until approximately 2035 
regardless of fishing mortality, the effect on stock status beyond this 
varies greatly with fishing mortality levels. Beyond the North Atlantic 
and North Pacific (where fishing data is also considered robust), 
fishing harvest and, especially, at-vessel and post-release mortality 
data are less thoroughly documented, introducing considerable 
uncertainty in projections of fishery impacts past a few decades.
    After considering the best available scientific and commercial 
information on the shortfin mako shark's life history, projected 
abundance trends, and current and future management measures and 
fishing behaviors, the ERA Team concluded that a biologically 
reasonable foreseeable future timeframe would be 25 years, or one 
generation length, for the shortfin mako shark. Because the main 
threats to the species are overutilization in commercial fisheries and 
the inadequacy of existing regulatory mechanisms to prevent 
overutilization in these fisheries, the ERA Team found that this 
timeframe would allow for reliable predictions regarding the likely 
impact of these threats on the future biological status of the species.
    While we conclude that the ERA Team assembled the best scientific 
and commercial information, it is the role of the agency rather than 
the team to determine the appropriate application of the agency's 
interpretations of key statutory terms and of agency policy to the 
factual record, and to ultimately determine the species' listing status 
under the ESA. Based on the best available scientific and commercial 
information, we disagree with the ERA Team's conclusion that the 
foreseeable future extends only 25 years, or one generation length, and 
have determined that application of a 50-year time frame is more 
appropriate in this case generally, though for some individual threats 
our ability to predict the specific trends and the species' responses 
is less robust than for others. We agree that fisheries mortality and 
inadequate regulatory mechanisms to address this threat are, and will 
continue to be, the main threats to the species. While we also agree 
with the ERA Team's characterization of the shortfin mako shark's life 
history, we find this information to indicate that it would take more 
than one generation length for effects of conservation actions to be 
reflected in abundance indices. During peer review of the Status Review 
Report, reviewers noted that changes in threats and conservation 
measures for shortfin mako sharks might take decades to become visible 
in the mature population, and all three reviewers were of the opinion 
that a longer time horizon would be appropriate. We find that the ERA 
Team unnecessarily limited the length of the foreseeable future by 
relying on statistical confidence levels for projected population 
trends. The 2009 M-Opinion, which for over a decade has provided the 
basis for NMFS's interpretation of this term, states that ``the 
foreseeable future for a given species is not limited to the length of 
time into the future for which a species' status can be quantitatively

[[Page 68247]]

modeled or predicted within predetermined limits of statistical 
confidence; however, uncertainties of any modeling efforts should be 
considered and documented.'' Although, as the ERA Team noted, 
uncertainty in abundance projections increases with the length of 
projections, we have determined that we can use available projections, 
our knowledge of the species' life history, and predicted levels of 
fishing mortality to inform what is likely to be the status of the 
species in a given region over a longer timeframe. Also, although 
changes in threats (i.e., fisheries removals) would be observable over 
a 25-year period, we do not find that this time period is sufficient to 
measure and understand the population-level response to these changes, 
which would only be observable over a longer time period given the 
species' late age-at-maturity (this was also noted by a reviewer during 
the peer review process of the Status Review Report). A 50-year 
timeframe would encompass the duration over which changes in 
productivity would be expected to occur and be measurable while also 
taking into account the considerable uncertainty in future management 
measures and population trends as described by the ERA Team. To 
conclude, we find that our knowledge of the species' life history and 
of the fisheries impacting the species allow us to reasonably determine 
the likely threats facing the species (overutilization for commercial 
purposes and the related inadequacy of existing regulatory mechanisms) 
and the species' likely response to these threats (reflected in 
abundance trends and other demographic factors) over approximately 50 
years, or two generation lengths. We therefore consider the foreseeable 
future to extend 50 years (two generation lengths) rather than 25 years 
as determined by the ERA Team.
    The ability to measure or document risk factors to a marine species 
is often limited, and quantitative estimates of abundance and life 
history information are often lacking altogether. Therefore, in 
assessing extinction risk of a species with limited data available from 
certain regions, it is important to include both qualitative and 
quantitative information. In assessing extinction risk to the shortfin 
mako shark, the ERA Team considered the demographic viability factors 
developed by McElhany et al. (2000) and the risk matrix approach 
developed by Wainwright and Kope (1999) to organize and summarize 
extinction risk considerations. The approach of considering demographic 
risk factors to help frame the consideration of extinction risk has 
been used in many of our status reviews (which can be accessed online 
at http://www.nmfs.noaa.gov/pr/species). In this approach, the 
collective condition of individual populations is considered at the 
species level according to four demographic viability factors: 
abundance, growth rate/productivity, spatial structure/connectivity, 
and diversity. These viability factors reflect concepts that are well-
founded in conservation biology and that individually and collectively 
provide strong indicators of extinction risk. To some extent these 
factors reflect the impacts that the operative threats have already had 
or are having on the species.
    Using these concepts, the ERA Team evaluated demographic risks by 
assigning a risk score to each of the four demographic risk factors. 
The contribution of each demographic factor to extinction risk was 
scored according to the following scale: 0--unknown risk, 1--low risk, 
2--moderate risk, and 3--high risk. Detailed definitions of the risk 
scores can be found in the Status Review Report. The scores were then 
tallied and summarized for each demographic factor. The ERA Team 
discussed the range of perspectives for each of the factors and the 
supporting data upon which they were based. ERA Team members were then 
given the opportunity to revise scores after the discussion if they 
felt their initial analysis had missed any pertinent data discussed in 
the group setting.
    The ERA Team also performed a threats assessment for the shortfin 
mako shark by evaluating each threat in terms of its contribution to 
the extinction risk of the species. The contribution of each threat to 
the species' extinction risk was scored on the following scale: 0--
unknown risk, 1--low risk, 2--moderate risk, and 3--high risk. The 
scores were then tallied and summarized for each threat, and the ERA 
Team again discussed the range of perspectives before providing final 
scores. As part of the threats assessment, the ERA Team considered the 
synergistic and combined effects of the threats acting together as well 
as individually. It should be emphasized that the scoring exercise for 
both demographic risks and threats was simply a tool to help the ERA 
Team members organize the information and assist in their thought 
processes for determining the overall risk of extinction for the 
shortfin mako shark, and is a common and well-accepted feature of our 
species assessments.
    Guided by the results from the demographic risk analysis and the 
threats assessment, the ERA Team members were asked to use their 
informed professional judgment to make an overall extinction risk 
determination for the shortfin mako shark. For this analysis, the ERA 
Team considered three levels of extinction risk: 1--low risk, 2--
moderate risk, and 3--high risk. Detailed definitions of these risk 
levels are as follows: 1 = Low risk: A species is at low risk of 
extinction if it is not at a moderate or high level of extinction risk 
(see ``Moderate risk'' and ``High risk'' below). A species may be at a 
low risk of extinction if it is not facing threats that result in 
declining trends in abundance, productivity, spatial structure, or 
diversity. A species at low risk of extinction is likely to show stable 
or increasing trends in abundance and productivity with connected, 
diverse populations; 2 = Moderate risk: A species is at moderate risk 
of extinction if it is on a trajectory that puts it at a high level of 
extinction risk in the foreseeable future (50 years in this case) (see 
description of ``High risk''). A species may be at moderate risk of 
extinction due to projected threats or declining trends in abundance, 
productivity, spatial structure, or diversity; 3 = High risk: A species 
with a high risk of extinction is at or near a level of abundance, 
productivity, spatial structure, and/or diversity that places its 
continued persistence in question. The demographics of a species at 
such a high level of risk may be highly uncertain and strongly 
influenced by stochastic or depensatory processes. Similarly, a species 
may be at high risk of extinction if it faces clear and present threats 
(e.g., confinement to a small geographic area; imminent destruction, 
modification, or curtailment of its habitat; or disease epidemic) that 
are likely to create present and substantial demographic risks.
    The ERA Team adopted the ``likelihood point'' method for ranking 
the overall risk of extinction to allow individuals to express 
uncertainty. Following this method, each ERA Team member distributed 10 
``likelihood points'' across the three extinction risk levels, 
representing the likelihood that the species falls into each risk 
category. Each Team member had the ability to cast points in more than 
one category to account for uncertainty, and the points that each Team 
member allocated across the categories summed to 10. This method has 
been used in previous NMFS status reviews (e.g., oceanic whitetip 
shark, Pacific salmon, Southern Resident killer whale, Puget

[[Page 68248]]

Sound rockfish, Pacific herring, and black abalone) to structure the 
ERA Team's thinking and express levels of uncertainty when assigning 
risk categories. After scores were provided, the ERA Team discussed the 
range of perspectives and the supporting data on which scores were 
based, and members were given the opportunity to revise scores if 
desired after the discussion. Likelihood points were then summed by 
extinction risk category. Other descriptive statistics, such as mean, 
variance, and standard deviation, were not calculated, as the ERA Team 
concluded that these metrics would add artificial precision to the 
results.
    Finally, consistent with the appropriately limited role of the 
Team, the ERA Team did not make ultimate recommendations as to whether 
the species should be listed as threatened or endangered. Rather, the 
ERA Team drew scientific conclusions about the overall risk of 
extinction faced by the shortfin mako shark under present conditions 
and in the foreseeable future based on an evaluation of the species' 
demographic risks and assessment of threats.
    Because we determined to adopt a different period of years as the 
``foreseeable future'' for the shortfin mako shark after the ERA Team's 
work concluded, we also present our own assessment of extinction risk 
over the foreseeable future (50 years or two generation lengths) in a 
later section of this document alongside the ERA Team's results.

Demographic Risk Analysis

Abundance

    The ERA Team assessed available abundance and trend information by 
region, including formal stock assessments, preliminary stock 
assessments using data-limited assessment methods, and standardized 
CPUE trends. There are no global abundance estimates available; 
however, using the formal stock assessments available for the North 
Atlantic and North Pacific, current abundance has been estimated at one 
million and eight million individuals, respectively (FAO 2019). Using 
the regional rates of change weighted by an area-based estimate of the 
size of each region as a proportion of the species' global 
distribution, the IUCN Red List assessment estimated global decline at 
46.6 percent over three generation lengths, with the particular years 
covered varying by region (Rigby et al. 2019). Although historical 
declines of varying degrees are evident across all oceans, current 
trends are mixed.
    As discussed previously, the most recent stock assessment for 
shortfin mako shark in the North Atlantic indicates a combined 90 
percent probability that the stock is in an overfished state and is 
experiencing overfishing (ICCAT 2017). The age-structured stock 
assessment model estimates historical declines in SSF from 1950 
(unfished condition) to 2015 at 50 percent, and recent declines (from 
2006-2015) at 32 percent (ICCAT 2017, FAO 2019). All nine assessment 
model runs were consistent, and together indicated that shortfin mako 
sharks in the North Atlantic have experienced historical declines 
(1950-2015) in total biomass of 47-60 percent, and recent declines 
(2006-2015) in total biomass of 23-32 percent (ICCAT 2017, FAO 2019). 
The 2019 update to the stock assessment projects that even with a zero 
TAC, there is a 53 percent probability that the North Atlantic stock 
will be rebuilt and not experiencing overfishing by 2045, and that 
regardless of TAC (in this case, TAC refers to all sources of mortality 
and is not limited to landings), the stock will continue declining 
until 2035 (ICCAT 2019). Overall, the ERA Team agreed that the findings 
from the stock assessment and projections were concerning. The ERA Team 
discussed how to appropriately interpret the stock assessment's focus 
on being rebuilt (SSF > SSFMSY) and without overfishing (F < 
FMSY) in the context of assessing extinction risk. As 
discussed previously in Abundance and Trends, while the fisheries 
management goal of rebuilding an overfished stock relates to achieving 
biomass levels that will allow for production of MSY, this can be 
significantly above the biomass levels necessary to ensure that a 
species is not in danger of extinction. While it will likely take 
decades for the stock to meet these fisheries management criteria 
(rebuilt and without overfishing), this does not indicate that the 
stock is at risk of becoming extirpated now or over the foreseeable 
future. Additionally, the ERA Team weighed the potential effects of the 
recent two-year North Atlantic shortfin mako shark retention 
prohibition on fishing mortality and abundance (ICCAT Recommendation 
21-09, discussed in Inadequacy of Existing Regulatory Mechanisms below, 
which entered into force on June 17, 2022). As data for each fishing 
year is not reported until the following calendar year, the effect of 
this measure on fishing mortality will not be easily assessed until 
2024 when the landings and discard data from 2023 can be analyzed. As 
noted above, the low productivity and slow population growth of 
shortfin mako shark may also mean that measurable impacts of this 
measure on abundance do not manifest for several years, when a new 
cohort enters the fishery. The Team concluded that there was 
significant uncertainty concerning both the effect of the measure and 
the future management of the stock after the two-year time period, and 
therefore did not significantly rely on any potential effect of the 
measure when drawing conclusions about the stock's abundance or trends.
    We agree with the ERA Team's assessment of abundance and related 
considerations in the North Atlantic. We also recognize that without a 
substantial reduction in total fishing mortality (annual TAC of 500 t 
or less), it is unlikely that the stock will be rebuilt by 2070 (ICCAT 
2019). Even if the spawning stock is not considered rebuilt by the 
stock assessment metric (SSF > SSFMSY), this does not 
necessarily mean that the stock will be in danger of being extirpated. 
However, given that fishing mortality is still high in this region 
(1,709 t in 2020) compared to even the greatest assessed TAC level 
(1,100 t), this level of removal will lead to continued declines. 
Unless aggressive management measures effectively reduce fishing 
mortality in this region, declines will likely continue throughout the 
foreseeable future (50 years). ICCAT has a demonstrated track record of 
taking multilateral actions to address data gaps and to respond to 
indications of declining stock status (see previous ICCAT measures 
specific to the stock in Inadequacy of Existing Regulatory Mechanisms 
below). The two-year retention prohibition adopted by ICCAT in 2021 is 
the most recent step that has been taken to conserve and manage this 
stock in line with the ICCAT Convention. ICCAT's track record would 
indicate that similar or additional measures are likely to be continued 
or taken, as needed, to ensure ICCAT's objectives of ending overfishing 
and rebuilding the stock to levels that support MSY are met. 
Recommendation 21-09 calls for the Commission to review the measure no 
later than the annual meeting in 2024 to consider additional measures 
to reduce total fishing mortality. Overall, we conclude that the best 
available scientific and commercial data indicate that the stock is 
overfished and experiencing overfishing, has experienced an estimated 
50 percent decline in SSF from 1950 to 2015, and will continue 
decreasing until 2035 regardless of TAC.
    The 2017 stock assessment for shortfin mako sharks in the South 
Atlantic indicated a high degree of

[[Page 68249]]

uncertainty. The combined assessment models found a 19 percent 
probability that the population is overfished and is experiencing 
overfishing (ICCAT 2017). The authors concluded that despite high 
uncertainty, in recent years the South Atlantic stock may have been at, 
or already below, BMSY and fishing mortality is likely 
exceeding FMSY (ICCAT 2017). Projections for the stock were 
not completed in 2019 due to high uncertainty. The ERA Team agreed that 
the best available scientific and commercial data indicate some degree 
of historical and ongoing population decline, but was unable to draw 
conclusions about the degree of decline due to the highly uncertain 
results of the 2017 stock assessment. We agree with the ERA Team's 
assessment of abundance in the South Atlantic.
    The most comprehensive information on trends for shortfin mako 
sharks in the North Pacific comes from the 2018 ISC Shark Working Group 
stock assessment, which found that the North Pacific stock was likely 
not in an overfished condition and was likely not experiencing 
overfishing between 1975 and 2016 (42 years) (ISC Shark Working Group 
2018). This assessment determined that the abundance of mature females 
was 860,200 in 2016, which was estimated to be 36 percent higher than 
the number of mature females at MSY (ISC Shark Working Group 2018). 
Future projections indicated that spawning abundance is expected to 
increase gradually over a 10-year period (2017-2026) if fishing 
mortality remains constant or is moderately decreased relative to 2013-
2015 levels (ISC Shark Working Group 2018). Using results from the ISC 
stock assessment, historical decline in abundance (1975-1985 to 2006-
2016) is estimated at 16.4 percent, and a recent increase (2006-2016) 
is estimated at 1.8 percent (CITES 2019). While the IUCN used the ISC 
assessment to model the average trend in the North Pacific stock over 
three generation lengths (72 years), resulting in a median decline of 
36.5 percent (Rigby et al. 2019), Kai (2021a) found a median decline of 
the population trajectory of 12.1 percent over three generation lengths 
with low uncertainty. The ERA Team concluded that despite evidence of 
historical decline, the best available scientific and commercial data 
indicate that shortfin mako sharks in the North Pacific are neither 
overfished nor experiencing overfishing, and the population is likely 
stable and potentially increasing. We agree with the ERA Team's 
conclusion.
    Although a stock assessment is not available for shortfin mako 
sharks in the South Pacific, available information indicates that the 
population is increasing. Standardized CPUEs for the mako shark complex 
(i.e., both shortfin and longfin mako shark) show a relatively stable 
trend in relative abundance, with low points in 2002 and 2014, though 
the 2014 point is based on relatively few data and should be 
interpreted with caution (Rice et al. 2015). In New Zealand waters, 
logbook and observer data from 1995-2013 analyzed by Francis et al. 
(2014) indicate that shortfin mako sharks were not declining, and may 
be increasing, over the period from 2005-2013. More recently, trend 
estimations using data from these two studies (Francis et al. 2014 and 
Rice et al. 2015) did not result in statistically significant trend 
fits for two of the data series; those that were significant were 
increasing (Japanese South 2006-2015, Domestic North 2006-2013, and 
Observer Data 2004-2013) (FAO 2019). Trend analysis of modeled biomass 
indicates a median increase of 35.2 percent over three generation 
lengths (Rigby et al. 2019). In sum, the ERA Team agreed that the best 
available scientific and commercial data for shortfin mako sharks in 
the South Pacific indicate an increasing population trend, and we agree 
with the ERA Team's conclusion.
    Finally, in the Indian Ocean, preliminary stock assessments using 
data-limited assessment methods are available for shortfin mako sharks 
and indicate that the stock is experiencing overfishing, but is not yet 
overfished (Brunel et al. 2018; Bonhommeau et al. 2020). This means 
that while the stock is subjected to a level of fishing mortality that 
jeopardizes the stock's ability to produce MSY, biomass levels are 
still high enough that the stock is able to produce MSY on a continuing 
basis. Both preliminary assessments are considered highly uncertain due 
to limitations in catch data. Using the results of the Schaefer model 
from Brunel et al. (2018), historical decline (1970-1980 to 2005-2015) 
was estimated at 26 percent, recent decline (2005 to 2015) was 
estimated at 18.8 percent, and future 10-year decline was projected at 
41.6 percent from the historic baseline (1970-1980 to 2015-2025) (CITES 
2019). A trend analysis for modeled biomass in the Indian Ocean using 
Brunel et al.'s assessment indicates a median decline of 47.9 percent 
over three generation lengths (Rigby et al. 2019). Recent increases in 
CPUE trends are indicated in Spanish, Portuguese, and Taiwanese 
longline fleets (Coelho et al. 2020; Ramos-Cartelle et al. 2020; Wu et 
al. 2021), though it should be noted that these datasets were included 
in the assessment by Bonhommeau et al. (2020). Overall, the ERA Team 
concluded that the best available scientific and commercial data 
indicate some level of historical population decline and indicate that 
shortfin mako sharks are currently experiencing overfishing in this 
region. We agree with the ERA Team's conclusion.
    The ERA Team considered the risk associated with abundance of the 
global species using the best available scientific and commercial 
information, summarized above. Reported landings represent a 
substantial underestimate of mortality resulting from fisheries 
interactions because they do not fully account for mortalities that 
result from fisheries interactions, including sharks that are discarded 
dead, finned, or that experience post-release mortality, and therefore 
there is some level of uncertainty in all available stock assessments 
and abundance indices, particularly so in the South Atlantic and Indian 
Oceans. However, stock assessments in the North Atlantic and North 
Pacific were considered robust by the ERA Team. Some degree of 
historical decline is indicated in all ocean basins, and population 
declines are ongoing in the North Atlantic. In the South Pacific, there 
are no available stock assessments, so the positive trends indicated 
here are based on available studies with limited geographic scope. 
Overall, there is no indication that global abundance has declined to 
the point that reproductive success of the species has declined or 
inbreeding has resulted, nor is there evidence of other depensatory 
processes associated with small populations. All ERA Team members 
agreed that the best available scientific and commercial information 
indicates that the species' abundance does not put it at risk of 
extinction currently. Several ERA Team members were of the opinion that 
declining abundance trends would likely contribute to the species' risk 
of extinction in the foreseeable future as they defined it; however, 
the majority of ERA Team members concluded that global abundance trends 
are unlikely to contribute significantly to the species' risk of 
extinction currently or in the foreseeable future as they defined it. 
We agree that this factor is not contributing significantly to the 
species' risk of extinction now.
    Over the foreseeable future of 50 years that we have determined is 
more appropriate to apply for this species, we find that the best 
available scientific and commercial data indicate that the abundance 
factor is unlikely to significantly contribute to the species'

[[Page 68250]]

extinction risk. The shortfin mako shark population in the Pacific 
Ocean basin (a major segment of the global population) is likely to be 
stable and/or potentially increasing over this time period. Despite 
historical levels of decline (estimated at 47-60 percent reduction in 
total biomass) and likely continued decreases in the North Atlantic 
until at least 2035 (there is the potential for the population to begin 
rebuilding after this time with appropriate reduction of fishing 
mortality through management measures), as well as potential continuing 
population decreases of unknown degrees in the Indian and South 
Atlantic Oceans, we conclude that the best available scientific and 
commercial information indicates that global population abundance will 
not likely decline to the point that will put the species at risk of 
extinction over this timeframe.

Productivity

    The shortfin mako shark exhibits high longevity (at least 28-32 
years; Natanson et al. 2006; Dono et al. 2015), slow growth rates, late 
age at maturity (6-9 for males and 15-21 years for females; Natanson et 
al. 2006; Semba et al. 2009), long gestation (9-25 months; Mollet et 
al. 2000; Duffy and Francis 2001; Joung and Hsu 2005; Semba et al. 
2011), and long reproductive cycles (3 years; Mollet et al. 2000; Joung 
and Hsu 2005). Cort[eacute]s (2016) determined that the intrinsic rate 
of population increase (rmax) for Atlantic shortfin mako 
sharks ranges from 0.036-0.134 yr-\1\. This was among the 
lowest values calculated from 65 populations and species of sharks. The 
ERA Team therefore concluded that the productivity of the species is 
quite low. The species also exhibits low natural mortality (0.075-0.244 
yr-\1\; Cort[eacute]s 2016) and a long generation time (25 
years; Cort[eacute]s et al. 2015). Together, the species' life history 
characteristics indicate that it is highly susceptible to depletion 
from exploitation or other high-intensity sources of mortality, and 
will recover slowly from declines brought on by such stressors. The ERA 
Team was largely in agreement that although this factor doesn't 
constitute a risk of extinction for the species currently, this factor 
would likely contribute significantly to the species' risk of 
extinction in the foreseeable future as they defined it, especially if 
exacerbated by impacts of fishing mortality and resulting declines in 
abundance. We agree that this factor is not contributing significantly 
to the species' risk of extinction now. Similarly, we find that the 
best available scientific and commercial data indicates that the 
shortfin mako shark's low productivity will likely contribute 
significantly to the species' extinction risk over the foreseeable 
future of 50 years that we have determined is more appropriate to apply 
for this species.

Spatial Structure/Connectivity

    Shortfin mako sharks are globally distributed across all temperate 
and tropical ocean waters and utilize numerous habitat types including 
open ocean, continental shelf, shelf edge, and shelf slope habitats 
(Rogers et al. 2015b; Corrigan et al. 2018; Francis et al. 2019; Rigby 
et al. 2019; Santos et al. 2020; Gibson et al. 2021). This highly 
migratory species is capable of undertaking movements of several 
thousand kilometers (Kohler and Turner 2019; Francis et al. 2019), and 
is able to make vertical migrations in the water column to several 
hundred meters depth (Santos et al. 2021). As a red muscle endotherm, 
the species is able to regulate its body temperature, allowing it to 
tolerate a broad range of water temperatures (Watanabe et al. 2015). 
Connectivity among ocean basins has been demonstrated by several 
genetic studies. Taken together, results of available genetic analyses 
suggest that female shortfin mako sharks exhibit fidelity to ocean 
basins, while males readily move across the world's oceans and mate 
with females from various basins, thereby homogenizing genetic 
variability (Heist et al. 1996; Schrey and Heist 2003; Taguchi et al. 
2011; Corrigan et al. 2018). The ERA Team unanimously agreed that, 
based on this information, this demographic factor is not likely to 
contribute significantly to the species' risk of extinction now or in 
the foreseeable future as they defined it. We agree that this factor is 
not contributing significantly to the species' risk of extinction now. 
Over the foreseeable future of 50 years that we have determined is more 
appropriate to apply for this species, we also find that this 
demographic factor is not likely to significantly contribute to the 
shortfin mako shark's risk of extinction because this factor is not 
currently negatively affecting the species' status and the best 
available scientific and commercial data suggests no basis to predict 
that this factor will change over the extended time horizon.

Diversity

    In its consideration of the degree to which diversity (or lack 
thereof) might contribute to the extinction risk of the shortfin mako 
shark, the ERA Team evaluated available information on genetic 
diversity as well as diversity of distribution and ecology. Available 
genetic studies do not indicate that the species has experienced a 
significant loss of diversity that would contribute to extinction risk. 
In fact, haplotype diversity has been found to be high in several 
studies: 0.755 by Heist et al. (1996), 0.92 by Taguchi et al. (2011), 
and 0.894 by Corrigan et al. (2018). Nucleotide diversity has been 
found to be lower: 0.347 by Heist et al. (1996), 0.007 by Taguchi et 
al. (2011), and 0.004 by Corrigan et al. (2018). Genetic studies 
indicate a globally panmictic population, meaning that there is 
sufficient movement of shortfin mako sharks, and therefore gene flow, 
to reduce genetic differentiation among regions (Heist et al. 1996; 
Schrey and Heist 2003; Taguchi et al. 2011; Corrigan et al. 2018). We 
found no evidence that gene flow, migration, or dispersal has been 
reduced. The species occurs across a variety of habitats and regions 
(Rogers et al. 2015b; Rigby et al. 2019; Santos et al. 2020), and is 
able to consume a diversity of prey (Stillwell and Kohler 1982; 
Cort[eacute]s 1999; Maia et al. 2006; Gorni et al. 2012); these 
characteristics protect against catastrophic events that may impact a 
certain region or prey species. For these reasons, the ERA Team 
unanimously agreed that it is not likely that this factor significantly 
contributes to the species' risk of extinction now or in the 
foreseeable future as they defined it. We agree that this factor is not 
contributing significantly to the species' risk of extinction now. 
Similarly, over the foreseeable future of 50 years that we have 
determined is more appropriate to apply for this species, we also find 
that this demographic factor is not likely to significantly contribute 
to the shortfin mako shark's risk of extinction because this factor is 
not currently negatively affecting the species' status and the best 
available scientific and commercial data suggests there is no basis to 
predict that this factor will change over the extended time horizon.

Summary and Analysis of Section 4(a)(1) Factors

    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; the inadequacy of existing 
regulatory mechanisms; or other natural or manmade factors affecting 
its continued

[[Page 68251]]

existence. The ERA Team assembled the best available scientific and 
commercial data and evaluated whether and the extent to which each of 
the foregoing factors contributed to the overall extinction risk of the 
global shortfin mako shark population. We summarize information 
regarding each of these threats below according to the factors 
specified in section 4(a)(1) of the ESA.

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

    The shortfin mako shark is a highly migratory, pelagic species that 
spends time in a variety of open ocean and nearshore habitat types. The 
species is globally distributed from about 50[deg] N (up to 60[deg] N 
in the northeast Atlantic) to 50[deg] S. While distribution is 
influenced by environmental variables including water temperature, prey 
distribution, and DO concentration, the shortfin mako shark is able to 
tolerate a broad thermal range and use a wide variety of prey 
resources. The ERA Team agreed that because shortfin mako sharks have a 
high adaptive capacity and do not rely on a single habitat or prey 
type, they are able to modify their distributional range to remain in 
an environment conducive to their physiological and ecological needs. 
Additionally, there is no evidence that range contractions have 
occurred, or that destruction or modification of their habitat on a 
global scale has occurred to such a point that it has impacted the 
status of the species. Therefore, the ERA Team concluded that the best 
available scientific and commercial information indicates that loss 
and/or degradation of habitat are not likely to be contributing 
significantly to the extinction risk of the shortfin mako shark now or 
in the foreseeable future as they defined it. We agree that this factor 
is not contributing significantly to the species' risk of extinction 
now. Because the contribution of habitat destruction, modification or 
curtailment to extinction risk is not likely to change from 25 to 50 
years, we also find that this factor will not contribute significantly 
to extinction risk over the foreseeable future of 50 years that we have 
determined is more appropriate to apply for this species.
    An analysis of potential threats posed by pollutants and 
environmental contaminants is carried out in Other Natural or Manmade 
Factors Affecting its Continued Existence, below, because this 
potential threat affects more than just the habitat or range of the 
species.

Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    The best available information indicates that the primary threat 
facing the shortfin mako shark is overutilization in fisheries. The 
majority of the catch is taken incidentally in commercial fisheries 
throughout the species' range, and the species is often 
opportunistically retained due to the high value of its meat and fins 
(Camhi et al. 2008; Dent and Clarke 2015). The species is targeted in 
semi-industrial and artisanal fisheries in the Indian and Pacific 
Oceans, and as a sportfish in several recreational fisheries, though 
recreational fisheries are thought to have minimal contribution to the 
species' overutilization in comparison to effects from commercial 
fisheries.
    Global reported catches of shortfin mako shark have risen 
substantially since 1980. According to the Food and Agriculture 
Organization of the United Nations (FAO) global capture production 
statistics (accessible at https://www.fao.org/fishery/statistics-query/en/capture/capture_quantity), reported catch for shortfin mako shark in 
the period 2010-2019 totaled 128,743 t, up from 86,912 t in the period 
2000-2009 and 29,754 t in the period 1990-1999. In the 2010-2019 time 
frame, reported landings in the Atlantic Ocean and adjacent seas 
totaled 61,673 t (~48 percent of global reported catch), in the Pacific 
Ocean totaled 43,927 t (~34 percent of global reported catch), and in 
the Indian Ocean totaled 23,143 t (~ 18 percent of global reported 
catch). Reported landings, however, represent a substantial 
underestimate of actual catch because they do not fully account for 
mortalities that result from fisheries interactions, including sharks 
that are discarded dead, finned, or that experience post-release 
mortality. For instance, Clarke et al. (2006) estimated that shark 
biomass in the fin trade alone is three to four times higher than catch 
reported in the FAO capture production data. Therefore, impacts of 
commercial fishing fleets on the shortfin mako shark are likely much 
greater than reported catch numbers suggest.
    Data from across the species' range indicate that much of the catch 
of shortfin mako sharks in longline fisheries is composed of immature 
individuals (N Atlantic: Biton-Porsmoguer 2018, Coelho et al. 2020a; S 
Atlantic: Barreto et al. 2016; NW Pacific: Ohshimo et al. 2016, Semba 
et al. 2021; E Pacific: Furlong-Estrada et al. 2017, Salda[ntilde]a-
Ruiz et al. 2019, Doherty et al. 2014; Indian: Winter et al. 2020, Wu 
et al. 2021). Exploitation of the juvenile life stage reduces the 
proportion of the population that survives to maturity to reproduce. 
Due to the late age-at-maturity of the species, many years are required 
before conservation actions may influence the spawning population. 
Additionally, abundance indices based on the part of the population 
that is most vulnerable to fisheries mortality (immature individuals) 
can be out of phase with those based on the abundance of the spawning 
stock (e.g., CPUE and age-structured population models, respectively) 
for decades. For these reasons, the delay between identifying 
overutilization and addressing it can limit the effectiveness of 
mitigation and can make fisheries management for the shortfin mako 
shark difficult.
    Rates of at-vessel mortality, or mortality resulting from 
interactions with fishing gear prior to being brought onboard (also 
known as hooking or capture mortality), vary by fishing practice and 
gear type. Campana et al. (2016) estimated fisheries mortality of 
shortfin mako sharks in Northwest Atlantic pelagic longline fisheries 
targeting swordfish and tuna, in which the majority (88 percent) of 
hooks used were circle hooks. The types of leaders or branch lines were 
not reported. Shortfin mako sharks were found to experience a mean at-
vessel mortality rate of 26.2 percent, and another 23 percent of 
incidentally caught shortfin mako sharks were injured at haulback 
(Campana et al. 2016). The proportion of shortfin mako sharks that 
experienced at-vessel mortality in pelagic longlines was significantly 
higher than that of blue sharks (Prionace glauca), likely because 
shortfin mako sharks have very high oxygen requirements, and their 
ability to ram ventilate--or continuously force water across their 
gills to breathe, typically by swimming at speed--is compromised once 
hooked (Campana 2016; Campana et al. 2016). Data from Portuguese 
longline vessels targeting swordfish in the North and South Atlantic 
indicate at-vessel mortality rates of 35.6 percent for shortfin mako 
shark (Coelho et al. 2012). This fleet uses stainless steel J hooks and 
both monofilament and wire branch lines (Coelho et al. 2012). In the 
North Pacific, shortfin mako sharks incidentally caught in the Hawaii 
deep-set and American Samoa longline fisheries targeting tuna were 
found to experience an at-vessel mortality rate of 22.7 percent 
(Hutchinson et al. 2021). Prior to May 2022, the Hawaii deep-set 
fishery used circle hooks, stainless steel braided wire leader, and 
monofilament; the American Samoa longline fishery

[[Page 68252]]

uses circle hooks and all monofilament branch lines (Hutchinson et al. 
2021). However, in May 2022, NMFS issued a final rule that prohibits 
the use of wire leader in the Hawaii deep-set longline fishery, which 
is anticipated to increase survivorship of incidentally caught sharks.
    Post-release (or discard) mortality rates are more difficult to 
accurately assess, although tag-recapture and telemetry studies 
indicate that they can be relatively low for shortfin mako sharks 
depending on factors such as hook type, hooking location, and handling. 
Reported estimates of post-release mortality rate also depend on the 
duration over which survival is assessed. Any mortality related to 
capture and handling that occurs after the monitoring period would 
cause post-release mortality rates to be underestimated (Musyl et al. 
2009, Musyl and Gilman 2019). Campana et al. (2016) estimated that 
shortfin mako sharks (n=26) caught incidentally in Northwest Atlantic 
pelagic longlines have post-release mortality rates of 30-33 percent 
over ~50 days. Bowlby et al. (2021) also investigated post-release 
mortality in North Atlantic pelagic longline fleets, estimating a rate 
of 35.8 percent for the species over the first 30 days from 104 tagging 
events. The post-release mortality rate of tagged shortfin mako sharks 
(n=35) after capture and release by pelagic longliners in the 
Northeast, Northwest, Equatorial, and Southwest Atlantic was estimated 
at 22.8 percent over the first 30 days (Miller et al. 2020). A 
telemetry study on post-release mortality rates of five shark species 
captured in the Hawaii deep-set and American Samoa tuna longline 
fisheries found relatively low post-release mortality rates for 
shortfin mako shark (6 percent), with only one mortality observed out 
of 18 tags that reported (Hutchinson et al. 2021). A Bayesian analysis 
of the post-release mortality rates from all sharks tagged (including 
shortfin mako shark) found that post-release fate was correlated with 
the animal's condition at the vessel, handling method, and the amount 
of trailing gear left on the animals, whereby animals that were left in 
the water and had most of the gear removed had the lowest mortality 
rates (Hutchinson et al. 2021). Another telemetry study conducted by 
the WCPFC in three longline fisheries in the South Pacific (New 
Caledonia, Fiji and New Zealand) with much larger sample sizes (n = 57 
shortfin mako shark tags) also found low post-release mortality rates 
for shortfin mako sharks: 11.6 percent of the tagged, uninjured 
shortfin mako sharks died within the 60-day monitoring period of the 
tags, and this estimate increased to 63.2 percent for injured shortfin 
mako sharks (Common Oceans (ABNJ) Tuna Project 2019). Similar to 
conclusions from Hutchinson et al. 2021, survival rates were higher 
when trailing gear was minimized, particularly in relation to the size 
of the animal. Although the practice of hauling sharks on deck was not 
found to have contributed to mortality, the probability of injury is 
higher when sharks are hauled onboard, and injured sharks are less 
likely to survive (Common Oceans (ABNJ) Tuna Project 2019). This 
suggests that improvements to handling and release methods can help 
reduce post-release mortality in shortfin mako shark and other shark 
bycatch species.
    In sum, bycatch mortality makes up a substantial amount of total 
fishery mortality that is not captured in reported landings data. Total 
non-landed fishery mortality for shortfin mako sharks in the Canadian 
pelagic longline fishery was estimated at 49.3 percent (95 percent CI: 
23-73 percent), indicating that even if retention of the species is 
prohibited, about half of shortfin mako sharks hooked by this fleet 
would die during or after fishing (Campana et al. 2016). Given that 
other nations targeting swordfish and tuna in the Northwest Atlantic 
and other ocean basins use similar gear configurations as used in the 
study by Campana et al. (2016), similar un-reported mortality levels 
may be expected if landings of shortfin mako shark were prohibited 
throughout its global range. Hook type, gear configuration, handling 
(i.e., bringing incidentally caught shortfin mako sharks on deck to 
remove gear) (Bowlby et al. 2021), and bait type (Coelho et al. 2012; 
Amorim et al. 2015; Fernandez-Carvalho et al. 2015) have been shown to 
influence catch and mortality rates of shortfin mako sharks (see the 
Status Review Report for a detailed review of this information).
    In the North Atlantic Ocean, shortfin mako sharks are incidentally 
caught mainly in pelagic and surface longlines, and to a lesser extent, 
purse seines, bottom trawls, and gillnets. There are no commercial 
fisheries targeting shortfin mako sharks in this region. Since 2017, 
and until only recently, ICCAT Contracting Parties and Cooperating Non-
Contracting Parties (CPCs) have been required to release live North 
Atlantic shortfin mako sharks in a manner that causes the least harm. 
Retention of dead North Atlantic shortfin mako sharks remained 
acceptable in many cases, and harvest of live individuals was only 
permitted under very limited circumstances. Reported landings for all 
CPCs in the North Atlantic (including dead discards) did decline in 
recent years, though numbers remain high (3,281 t in 2015; 3,356 t in 
2016; 3,199 t in 2017; 2,373 t in 2018; 1,882 t in 2019; 1,709 t in 
2020) (SCRS 2021). Over 90 percent of recent shortfin mako shark catch 
in the North Atlantic is attributable to Spain (longline fleet 
targeting swordfish), Morocco (longline fleet targeting swordfish and 
purse seine), and Portugal (longline fleet targeting swordfish), with 
Spain harvesting nearly half of the North Atlantic catch in 2019 (866 t 
reported). These three countries have each recently announced 
unilateral retention bans. In early 2021, Spain announced a moratorium 
on the landing, sale, and trade of North Atlantic shortfin mako shark. 
The retention ban reportedly applies to 2021 catches from all Spanish 
vessels, whether operating in domestic water or on the high seas, and 
the ban on sale and trade extends to a 90 t stockpile of all mako shark 
fins landed by Spanish vessels in 2020. Shortly afterwards, Portugal 
announced a moratorium on landings of shortfin mako sharks caught in 
the North Atlantic high seas fisheries, the source of the majority of 
Portugal's mako shark catch. In February 2022, the government of 
Morocco announced a 5-year national prohibition on the fishing, 
storage, and trade of shortfin mako shark. Due to at-vessel and post-
release mortality, retention bans will not eliminate fishery mortality. 
However, because approximately 50 percent of catches would be expected 
to survive as discussed above, these retention bans may significantly 
reduce shortfin mako shark mortality in pelagic longline fleets 
operating in the North Atlantic, and therefore overall mortality in 
this region.
    Shortfin mako sharks are incidentally caught by the U.S. pelagic 
longline fleets targeting swordfish and tuna (Thunnus spp.), including 
in the Gulf of Mexico and the Caribbean Sea. A total of 2,406 t of 
shortfin mako shark was landed and sold by this fishery between 1985 
and 2008, valued at $4,562,402 (Levesque 2013). Commercial landings of 
incidentally caught shortfin mako shark ranged from 17.6 t in 1985 to 
266.8 t in 1993, with a mean of 100.24 t year\-1\ (Levesque 2013). As 
described below in Inadequacy of Existing Regulatory Mechanisms, after 
the 2017 ICCAT stock assessment indicated that North Atlantic shortfin 
mako sharks were overfished and experiencing overfishing, the United 
States took immediate action to end overfishing and work towards

[[Page 68253]]

rebuilding of the stock through emergency rulemaking. These measures 
led to a reduction in North Atlantic shortfin mako shark landings by 
the U.S. longline fleet, with 112 t landed in 2017, 42 t landed in 
2018, and 33 t landed in 2019 (NMFS 2021). Shortfin mako shark catch in 
U.S. pelagic longlines represented only 0.8 percent of total 
international longline catch of the species across the entire Atlantic 
Ocean in 2019 (NMFS 2021), and due to the poor reporting of other ICCAT 
CPCs, this percentage is likely significantly lower. A detailed 
overview of other fleets that contribute to shortfin mako shark 
mortality in the North Atlantic can be found in the Status Review 
Report.
    Risk assessments have repeatedly found shortfin mako sharks to be 
at high risk of overexploitation by pelagic longline fisheries in the 
North Atlantic. Using an ecological risk assessment, the inflection 
point of the population growth curve (a proxy for BMSY), and 
IUCN Red List status, Simpfendorfer et al. (2008) found the shortfin 
mako shark to have the highest risk among the pelagic shark species 
taken in Atlantic longline fisheries. Similar results were found by 
Cort[eacute]s et al. (2010) in an ecological risk assessment of 11 
pelagic elasmobranchs across the North and South Atlantic, which 
incorporated estimates of productivity (intrinsic rate of increase, r) 
and susceptibility to the fishery (a product of the availability of the 
species to the fleet, encounterability of the gear given the species' 
vertical distribution, gear selectivity, and post-capture mortality). 
The authors found the shortfin mako shark to be at high risk of 
overexploitation (Cort[eacute]s et al. 2010). In an expanded 
assessment, the shortfin mako shark's low productivity (r=0.058 
year-\1\) and high susceptibility to capture (0.220, 
calculated as the product of four factors: availability of the species 
to the fleet, encounterability of the gear given the species' vertical 
distribution, gear selectivity, and post-capture mortality) continued 
to give the species one of the highest risks of overexploitation of 
sharks caught by Atlantic pelagic longline fleets (Cort[eacute]s et al. 
2015).
    In the North Atlantic, fisheries mortality has led to substantial 
population declines, and the stock is currently both overfished and 
experiencing overfishing. ICCAT Recommendations 17-08 and 19-06 have 
required live shortfin mako sharks to be released except in very 
limited circumstances since 2017, though reported landings are still 
high (1,709 t in 2020, inclusive of dead discards (SCRS 2021)). The ERA 
Team considered whether a newly adopted retention prohibition 
(Recommendation 21-09) would be adequate to reduce fishing mortality 
and allow the stock to begin to rebuild, given that at-vessel mortality 
will not be addressed by this measure. Given the status of the stock, 
the continued high level of fishing effort, high catches, and low 
productivity, the ERA Team concluded, and we agree, that the best 
available scientific and commercial information indicates that 
overutilization of shortfin mako shark is occurring in the North 
Atlantic Ocean. Recent management measures may decrease the degree to 
which overutilization threatens the species over the foreseeable future 
(50 years), although this depends on whether current management 
measures are effectively implemented, and whether additional management 
measures, including measures addressing fishing gear and behavior, are 
implemented in the future (this is discussed further in Inadequacy of 
Existing Regulatory Mechanisms).
    Shortfin mako sharks are frequently incidentally caught in pelagic 
longlines in the South Atlantic, where fishing effort has been 
increasing since the 1970s (Barreto et al. 2016). Recent reported 
landings and dead discards of South Atlantic shortfin mako shark by all 
ICCAT CPCs are as follows: 2,774 t in 2015; 2,765 t in 2016; 2,786 t in 
2017; 3,158 t in 2018; 2,308 t in 2019; 2,855 t in 2020 (SCRS 2021). An 
analysis of historical catches in longline fishing fleets in the South 
Atlantic found three distinct phases of fishery exploitation: phase A 
(1979-1997), characterized by the use of deep multifilament line with J 
hooks to target tunas; phase B (1998-2007), during which monofilament 
lines and circle hooks were used to target sharks and tunas, and phase 
C (2008-2011), during which several measures regulating shark fishing 
came into effect (Barreto et al. 2016). The authors found that 
standardized catch rates of shortfin mako shark from a zero-truncated 
model increased 8-fold in phase A (1979-1997), decreased by 55 percent 
in phase B (1998-2007), and increased 1.3-fold in phase C (2008-2011), 
even though nominal catch rates for all sharks combined were highest in 
phase B. Dramatic catch rate declines in phase B coincided with 
significant fishing effort increases as well as a lack of regulatory 
measures, and Barreto et al. (2016) conclude that shortfin mako sharks 
are depleted in the South Atlantic.
    Significant contributors to South Atlantic shortfin mako shark 
landings as reported by the ICCAT SCRS are Spain, Namibia, Brazil, 
Portugal, and South Africa. Spanish longline fleets in the South 
Atlantic reported shortfin mako shark catches of 1,049 t in 2017, 1,044 
t in 2018, 1,090 t in 2019, and 799 t in 2020 (SCRS 2021). The Spanish 
fleet has retained the vast majority of shortfin mako shark bycatch due 
to the high value of the species. Therefore, catches and landings have 
been roughly equivalent since the beginning of this fishery (Mejuto et 
al. 2009). In Brazil, pelagic longline vessels targeting tuna have been 
fishing since 1956, and part of the longline fleet shifted to targeting 
swordfish in 1994 (Lucena Fr[eacute]dou et al. 2015). Although there 
are no directed fisheries for shortfin mako shark in the South 
Atlantic, the species is frequently retained due to its high value, and 
is one of eight shark species commonly caught in the Brazilian longline 
fleet (Lucena Fr[eacute]dou et al. 2015). Data from 2004-2010 indicate 
that mako sharks (shortfin and longfin combined, though longfin are 
rarely caught) were the second most common shark, making up 5.4 percent 
of all individuals caught (Lucena Fr[eacute]dou et al. 2015). Reported 
catch has been increasing in Brazil over the past few years: 124 t in 
2016, 275 t in 2017, 399 t in 2018, 739 t in 2019, and 542 t in 2020 
(no discards have been reported) (SCRS 2021). The South African pelagic 
longline fleet targeting tuna and swordfish operates in South Africa's 
Exclusive Economic Zone (EEZ) where the Southeast Atlantic meets the 
Southwest Indian Ocean. Based on landings, logbook, and observer data, 
the South African pelagic longline fleet was estimated to catch 50,000 
shortfin mako sharks in 2015, with less than 1,000 estimated to have 
been released in good condition (Jordaan et al. 2020). In total, 96 
percent of hooked shortfin mako sharks were retained, and of those 
discarded, 82 percent were dead (Jordaan et al. 2020). Most of the 
shortfin mako shark catch occurred in waters of the Indian Ocean and 
was, therefore, reported to the IOTC; smaller quantities of the species 
are caught in Atlantic waters (Jordaan et al. 2020). There have been 
steep increases in fishing effort (from 0.45 million hooks set in 2000 
to 1.7 million hooks set in 2015) as well as shortfin mako shark 
fishing mortality in the South African pelagic longline fleet (Jordaan 
et al. 2018). Additional information on fishing practices of other 
fleets that contribute to shortfin mako shark mortality in the South 
Atlantic can be found in the Status Review Report.
    In the South Atlantic, the shortfin mako shark has an overall 19 
percent probability of being overfished with overfishing occurring 
(ICCAT 2017). Data quality in the South Atlantic is

[[Page 68254]]

poor, and the stock assessment in this region has high uncertainty. 
Therefore, given the high fishing effort and low productivity of the 
species, the ERA Team concluded, and we agree, that the best available 
scientific and commercial data indicate that overutilization may be 
occurring in the South Atlantic.
    In the Western and Central Pacific Ocean, shortfin mako sharks 
commonly interact with longline fisheries and are more rarely targeted 
by certain fleets. Fisheries information and catch data for this region 
are available from the WCPFC, and although historical catch data are 
lacking, reporting has improved in recent years with required reporting 
of catches of key shark species. Despite reporting requirements, recent 
catches of key shark species have not been provided to the WCPFC for a 
number of longline fleets, including Indonesia, which is the top shark 
fishing nation in the world (Dent and Clarke 2015; Okes and Sant 2019). 
Fleets with the highest reported numbers of shortfin mako sharks caught 
in recent years (as reported in WCPFC data catalogs available at 
https://www.wcpfc.int/data-catalogue) include Taiwan, the United States 
(Hawaii), Japan, Spain, and New Zealand. In the western North Pacific, 
Taiwanese coastal and offshore longline fishing vessels mainly target 
dolphinfish (also known as mahi mahi; Coryphaena hippurus), tunas, and 
billfishes from April to October, and switch to targeting sharks by 
changing gear configuration from November to March (Liu et al. 2021a). 
Liu et al. (2021a) carried out a productivity-susceptibility analysis 
for these Taiwanese fleets, where intrinsic rate of population growth 
(r) was used to express productivity, and susceptibility was estimated 
by multiplying catchability, selectivity, and post-capture mortality. 
Based on the shortfin mako shark's low productivity (r = 0.0300) and 
high susceptibility (1.1754), the authors found the species to be at 
highest ecological risk. However, when conducting an integrated ERA 
(incorporating the ERA, IUCN Red List index, annual body weight 
variation trend, and the inflection point of population growth curve), 
Liu et al. (2021a) found the species to be in the least risk group, 
possibly because the average body weight of the species in the western 
North Pacific has not experienced significant decline. The authors 
found this result to be reasonable as the latest stock assessment for 
North Pacific shortfin mako shark indicates that the stock is not 
overfished and overfishing is not occurring. The shortfin mako shark is 
one of the most commonly caught shark species in the Taiwanese large-
scale tuna longline fleet. Taiwan's catch of mako sharks (shortfin and 
longfin) in all longline fleets as reported in WCPFC data catalogs are 
high in the most recent 6 years of data: 1,216 t in 2015; 1,073 t in 
2016; 1,088 t in 2017; 1,146 t in 2018; 1,680 t in 2019; and 1,665 t in 
2020.
    While there are no directed commercial fisheries for shortfin mako 
sharks in Hawaii, the species is caught relatively frequently in the 
Hawaii-based pelagic longline fishery targeting swordfish in the 
shallow-set sector, and bigeye tuna (Thunnus obesus) in the deep-set 
sector (Walsh et al. 2009; Carvalho 2021). Substantially higher numbers 
of shortfin mako sharks are caught in the deep-set sector than the 
shallow-set sector. From 1995-2006, shortfin mako sharks made up 2.9 
percent of all observed shark catch in Hawaii-based pelagic longline 
fisheries, with higher nominal CPUE rates in the shallow-set sector 
than the deep-set sector (Walsh et al. 2009). Between 1995-2000 and 
2004-2006, catch rates for shortfin mako sharks were stable for the 
deep-set sector, and increased 389 percent in the shallow-set sector to 
0.911 sharks per 1000 hooks (Walsh et al. 2009). Comparing the same two 
time periods, minimum estimates of shortfin mako shark mortality 
decreased in both the deep-set and shallow-set sectors (from 80.6 to 47 
percent, and from 68 to 31.6 percent, respectively) (Walsh et al. 
2009). This reduction in mortality may be a result of the prohibition 
of shark finning in 2000, and the requirement of the use of relatively 
large circle hooks rather than traditional J-hooks in the shallow-set 
sector beginning in 2004 (Walsh et al. 2009; Carvalho et al. 2014). 
Data from Hawaii and California-based Pelagic Longline Vessels Annual 
Reports (available at https://www.fisheries.noaa.gov/resource/data/hawaii-and-california-longline-fishery-logbook-summary-reports) 
indicate that from 2008 to 2019, Hawaii longline fisheries have 
steadily increased the portion of mako catch that is released alive, 
with 58 percent being released alive in 2008 and 89 percent being 
released alive in 2019. Data from the report also shows that from 2008 
to 2019, mako sharks comprised, on average, only 0.71 percent of all 
species landed in the shallow-set and deep-set fisheries combined. 
Additional information on other fleets that contribute to shortfin mako 
shark mortality in the Western and Central Pacific Ocean can be found 
in the Status Review Report.
    Although historical catch data for the Western and Central Pacific 
are lacking, reporting has improved in recent years with the 
implementation of conservation and management measures that require 
reporting of catches of key shark species. A noteworthy exception are 
catches from Indonesia, recognized as the top shark fishing nation in 
the world. Interactions with shortfin mako shark commonly occur in 
pelagic longline fleets in this region. While RFMOs, and therefore 
landings data, fishing practices, and regulatory measures, are divided 
into the Eastern and Western and Central Pacific, abundance data in the 
Pacific are separated by North and South Pacific. Therefore, we take 
into consideration abundance data available for both the North and 
South Pacific when assessing overutilization of the Western and Central 
Pacific shortfin mako shark population. The latest stock assessment for 
shortfin mako sharks in the North Pacific indicates that the stock is 
not overfished and overfishing is not occurring, and CPUE trends from 
the South Pacific indicate increasing shortfin mako shark abundance. 
Based on the best available scientific and commercial data on current 
and historical levels of fishing mortality and abundance, the ERA Team 
concluded that overutilization is not likely occurring in the Western 
and Central Pacific Ocean, and we agree.
    In the Eastern Pacific Ocean, the species is mainly taken as 
bycatch in commercial longline, drift gillnet, and purse seine fleets 
(Read 2008). According to the Inter-American Tropical Tuna Commission's 
(IATTC) Report on the tuna fishery, stocks, and ecosystem in the 
Eastern Pacific Ocean in 2020, purse seine fisheries have contributed 
very little to the take of mako sharks (Isurus spp.) in the Eastern 
Pacific from 1993-2020 (estimated <3 t each year on average). Longline 
vessels are a more important source of fishery mortality for the genus 
in the Eastern Pacific Ocean. Estimated catch of mako sharks (Isurus 
spp.) was 2,882 t in 2018 and 1,927 t in 2019, and the total estimated 
catch in longlines from 1993-2019 was 36,036 t (IATTC 2020). The 
California/Oregon drift gillnet fishery targeting swordfish and 
thresher sharks incidentally catches shortfin mako sharks, the large 
majority of which are retained. Annual landings of the species ranged 
from 278 t in 1987 to 31 t in 2006, and have annually declined since 
the late 1990s (Read 2008; Sippel et al. 2014). Analysis of NMFS 
observer records from 1990-2015 indicates that shortfin mako sharks 
make up only 4.92 percent of the total catch in this fishery (Mason et 
al. 2019). Within Mexico's

[[Page 68255]]

EEZ in the Pacific, shortfin mako sharks are taken in the artisanal 
fishery and the pelagic longline fishery, and were historically taken 
in the drift gillnet fishery until 2010 (Sosa-Nishizaki et al. 2017). 
Gillnet and longline fleets in Ecuador and Peru also contribute to 
catch of the species in this region (Alfaro-Shigueto et al. 2010; 
Doherty et al. 2014; Martinez-Ortiz et al. 2015). Additionally, despite 
being defined as small-scale, Peruvian longline fisheries targeting 
dolphinfish have a high magnitude of fishing effort and proportion of 
juvenile shortfin mako sharks landed; this may have a large effect on 
the population off of Peru. Additional information on other fleets that 
contribute to shortfin mako shark mortality in the Eastern Pacific can 
be found in the Status Review Report.
    While RFMOs, and therefore landings data, fishing practices, and 
regulatory measures, are divided into the Eastern and Western and 
Central Pacific, abundance data in the Pacific are separated by North 
and South Pacific. Therefore, we take into consideration abundance data 
available for both the North and South Pacific when assessing 
overutilization of the Eastern Pacific shortfin mako shark population. 
The latest stock assessment for shortfin mako shark in the North 
Pacific indicates that the stock is not overfished and overfishing is 
not occurring. CPUE trends available from a variety of fisheries in the 
South Pacific indicate population increases, although a stock 
assessment is not available for this region. Despite this lack of a 
cohesive population model, the available data indicate flat or 
increasing abundance trends in the South Pacific. Based on the best 
available scientific and commercial data on current and historical 
levels of fishing mortality and abundance, the ERA Team concluded, and 
we agree, that overutilization is not demonstrably occurring in the 
Eastern Pacific Ocean, despite variation in the certainty associated 
with estimates.
    In the Indian Ocean, shortfin mako sharks are caught in pelagic 
longline, gillnet, and purse seine fleets, with the majority of catch 
coming from longlines targeting swordfish and sharks. Nominal reported 
catches of sharks in the IOTC Convention area have generally been 
increasing since the 1950s, though reporting of shark catches has been 
very irregular and information on shark catch and bycatch is considered 
highly incomplete (Murua et al. 2018). Fisheries catch data for the 
Indian Ocean are available from the IOTC, which requires CPCs to 
annually report shortfin mako shark catch data (IOTC Resolutions 17/05, 
15/01, and 15/02). However, prior to the adoption of resolution 05/05 
in 2005 (superseded by resolution 17/05 in 2017), there was no 
requirement for sharks to be recorded at the species level in logbooks. 
It was not until 2008 that some statistics became available on shark 
catch, mostly representing retained catch and not accounting for 
discards (IOTC 2018). Several countries continue to not report on their 
interactions with bycatch species as evidenced by high rates of bycatch 
reported by other fleets using similar gear configurations (IOTC 2018). 
When catch statistics are provided, they may not represent total 
catches of the species, but those simply retained on board, with 
weights that likely refer to processed specimens (IOTC 2018). 
Misidentification of shark species is also a common problem, and 
reporting by species is very uncommon for gillnet fleets where the 
majority of shark catches are reported as aggregates (IOTC 2020). 
Reported shark catches dropped significantly after 2017 when India 
stopped reporting aggregated shark catches and did not replace that 
reporting with detailed reports by species. Decreases in reported shark 
catches by Mozambique and Indonesia are thought to represent similar 
reporting issues (IOTC 2020). In sum, although reporting has improved 
substantially in recent years, there is a lack of historical data that 
does not allow for establishment of long-term trends, and current 
reported catches continue to be incomplete and largely underestimated. 
The major contributors to mako shark (longfin and shortfin combined) 
catch reported to IOTC are Japan, Madagascar, Indonesia, Spain, Sri 
Lanka, Pakistan, Taiwan, South Africa, Portugal, and Guinea. A detailed 
overview of fleets that contribute to shortfin mako shark mortality in 
the Indian Ocean can be found in the Status Review Report.
    Using the methodology of Cort[eacute]s et al. (2010), a preliminary 
Productivity-Susceptibility Analysis for sharks caught in IOTC longline 
fisheries revealed that shortfin mako sharks have among the highest 
vulnerability to overexploitation in this fishery due to the species' 
low productivity ([lambda]=1.061) and high susceptibility (0.929) 
(Murua et al. 2012). In an updated ecological risk assessment of IOTC 
longline, gillnet, and purse seine fisheries, Murua et al. (2018) found 
that the most vulnerable species to the IOTC pelagic longline fleet is 
the shortfin mako shark based on its low productivity ([lambda]=1.059) 
and high susceptibility (0.867). Shortfin mako sharks had lower 
susceptibility to catch in the purse seine and gillnet fisheries (0.129 
and 0.318, respectively) and were therefore found to be less vulnerable 
to overexploitation by these fleets (Murua et al. 2018). The post-
capture mortality rate in Indian Ocean purse seine fleets was reduced 
between the 2012 and 2018 assessments due to the European fleet 
implementing safe release best practices in 2014, but is still quite 
high for shortfin mako sharks (approximately 55 percent) (Murua et al. 
2018). Post-capture mortality represents the proportion of captured 
animals that die as a result of interaction with the gear, calculated 
as the sum of landings and dead discards (Cortes et al. 2010).
    Available preliminary stock assessments for shortfin mako sharks in 
the Indian Ocean indicate that overfishing is occurring but the stock 
is not yet overfished. Underreporting of catch is suspected to be 
continuing in this region, and the ERA Team therefore had low certainty 
that these assessments accurately reflect the status of the species 
here. However, recent CPUE trends in certain fleets indicate increasing 
abundance trends in this region. The ERA Team concluded that, while 
overutilization in commercial fisheries is likely impacting shortfin 
mako sharks in the Indian Ocean, the severity of this threat is highly 
uncertain. The best available scientific and commercial information on 
current and historical levels of fishing mortality and abundance 
indicates that overutilization is likely impacting the species in this 
region to some degree, and will continue to impact the species in this 
region over the foreseeable future (50 years).
    Demand for shark products, specifically meat and fins, has rapidly 
increased over the last 4 decades and has led to the overexploitation 
of shark populations worldwide. While trade in shark fins appears to 
have decreased slightly since the early 2000s, the trade in shark meat 
has grown over the last decade or so (Dent and Clarke 2015). In fact, 
domestic shark meat consumption in India is indicated to be the main 
driver of local shark harvest rather than the global fin trade (Karnad 
et al. 2020). The vast majority of shark fins in international trade 
are imported into and consumed in East and Southeast Asia, including 
China, Hong Kong, Taiwan, Singapore, Malaysia, and Vietnam, while the 
largest importers and consumers of shark meat include Italy, Brazil, 
Uruguay, and Spain (Dent and Clarke 2015). Spain, Indonesia, Taiwan, 
and Japan are the major shark fin exporting producers, and as the trade 
in shark meat has increased in recent years, these producers have also 
begun exporting large volumes of shark meat to

[[Page 68256]]

the markets in Italy and Brazil (Dent and Clarke 2015). While available 
data on the trade in shark products are incomplete due to inconsistent 
identification of species and tracking of product types and volumes, 
FAO statistics conservatively estimate the average declared value of 
total world shark fin imports at $377.9 million per year from 2000-
2011, with an average annual volume imported of 16,815 t (Dent and 
Clarke 2015). Annual average figures for shark meat from 2000-2011 were 
107,145 t imported, worth $239.9 million (Dent and Clarke 2015). 
Quantifying the amount of individual sharks harvested for the 
international shark trade is more difficult given that a substantial 
proportion of harvest is illegal, unregulated, or unreported (Clarke et 
al. 2006b). Using shark fin trade data to estimate the total number of 
sharks traded worldwide, Clarke et al. (2006b) found that between 26 
and 73 million individual sharks of all species are traded annually 
(median = 38 million each year), with a median biomass estimate of 1.70 
million t per year (range: 1.21-2.29 million t each year).
    Shortfin mako sharks are commonly retained for their highly valued 
meat when incidentally caught, with fins often kept as a by-product 
(Fowler et al. 2021). The meat is utilized fresh, frozen, smoked, 
dried, and salted for human consumption (CITES 2019; Dent and Clarke 
2015). Shortfin mako shark liver oil, teeth, jaws, and skin are also 
traded, though most of these products are of lower value and are not 
traded in significant quantities (CITES 2019).
    The shortfin mako shark is a preferred species in the Hong Kong fin 
market, one of the largest fin trading markets in the world (Fields et 
al. 2018). Clarke et al. (2006a) analyzed 1999-2001 Hong Kong trade 
auction data in conjunction with species-specific fin weights and 
genetic information to estimate the annual number of globally traded 
shark fins. The authors estimated that the shortfin mako shark makes up 
approximately 2.7 percent (95 percent probability interval: 2.3-3.1 
percent) of the Hong Kong shark fin trade, the fourth highest 
proportion of auctioned fin weight after blue (17.3 percent), 
hammerhead (Sphyrna zygaena or S. lewini, 4.4 percent) and silky 
(Carcharhinus falciformis, 3.5 percent) sharks. This translates to an 
estimated 300,000-1,000,000 shortfin mako sharks utilized in the global 
shark fin trade each year, totaling between 20,000 and 55,000 t in 
biomass (Clarke et al. 2006b). Although these data are fairly dated, 
more recent studies demonstrate the continued prevalence of shortfin 
mako shark fins in international trade. Fields et al. (2018) found 
shortfin mako shark to be the ninth most commonly traded species in 
Hong Kong based on random samples of fin trimmings from retail markets, 
making up 2.77 percent of fin trimming samples and comprising 0.6 
percent of modeled trimmings. In another recent study, shortfin mako 
shark fins made up 4.16 percent and 2.37 percent of samples taken in 
the fin markets of Guangzhou, the largest fin trade hub in mainland 
China, and Hong Kong, respectively (Carde[ntilde]osa et al. 2020).
    Shortfin mako sharks were listed under Appendix II of the 
Convention on International Trade in Endangered Species of Wild Fauna 
and Flora (CITES) effective November 26, 2019. As such, exports of the 
species must be found to be non-detrimental to the survival of the 
species in the wild and the specimen must have been legally acquired. 
As the numbers presented above predate the CITES listing of shortfin 
mako sharks, current levels of exploitation for the international trade 
in meat and fins may be lower than prior to the listing (this 
regulatory measure is discussed further in Inadequacy of Existing 
Regulatory Mechanisms). With the trade in shark meat on the rise, the 
preference for shortfin mako shark meat in addition to their continued 
prevalence in the fin trade presents a concern for overutilization of 
the species.
    Several ERA Team members cited the estimation by Clarke et al. 
(2006b) that 300,000-1,000,000 shortfin mako sharks may be utilized in 
the global shark fin trade each year in their assessment of this 
threat. Although this is not a recent study, and recent regulatory 
mechanisms may reduce pressure from the fin trade on this species, this 
estimate is still cause for concern given the low productivity of the 
species. Considering the recent declines in the fin trade and increases 
in the meat trade, the ERA Team generally concluded, and we agree, that 
the preference for shortfin mako shark meat (in addition to fins) 
presents a concern for overutilization of the species in the future.
    After considering the best available scientific and commercial 
data, several conclusions are indicated. Overall, although catch and 
mortality data are underreported globally, with very low confidence in 
data from both the Indian and South Atlantic Oceans, the ERA Team 
recognized the ESA's requirement to consider the best scientific and 
commercial data available, as summarized above and detailed in the 
Status Review Report. The majority of ERA Team members concluded that 
overutilization of the shortfin mako shark for commercial purposes (in 
both fisheries and trade) is not likely currently significantly 
contributing to the species' status but will likely contribute to the 
extinction risk of the species in the foreseeable future as they 
defined it, especially if management measures are inadequate. We agree 
with the ERA Team that overutilization for commercial purposes is not 
likely contributing significantly to the shortfin mako shark's risk of 
extinction now. However, over the foreseeable future of 50 years that 
we have determined is more appropriate to apply for this species, we 
conclude that overutilization for commercial purposes is likely to 
contribute to its risk of extinction. Recent management measures in the 
North Atlantic (including retention prohibitions adopted by ICCAT and 
by the top three shortfin mako shark-catching nations in the region) 
indicate increasing international efforts to reduce the effects of 
fishing mortality on the species in this region. Specifically, 
Recommendation 21-09 prohibits harvest of live individuals (previously 
allowed under limited circumstances) and contains strong provisions to 
improve data reporting, and particularly, the catch reporting of live 
releases and fish discarded dead. The measure does not require changes 
to fishing behavior or gear, and therefore will not address at-vessel 
or post-release mortality of incidentally caught shortfin mako sharks. 
Because of ICCAT's track record of taking multilateral conservation and 
management actions for the stock in response to indications of 
declining status, we have a reasonable basis to predict that similar or 
additional measures are likely to be continued or taken, as needed, to 
ensure ICCAT's objectives of ending overfishing and rebuilding the 
stock to levels that support MSY are met. While it is likely that the 
level of overutilization in this region will decline to some degree 
over the foreseeable future due to these efforts, it is unclear if 
Recommendation 21-09 will reduce mortality to a point that will allow 
the North Atlantic stock to rebuild. The low productivity of the 
shortfin mako shark means that the biological response to the measure 
will likely not be detectable for many years, despite assessment 
efforts. Therefore, at this time it is not possible to assess the 
adequacy of this measure to address the ongoing threat of overfishing 
in the North Atlantic. In the South Atlantic Ocean, fishing effort has 
been increasing

[[Page 68257]]

since the 1970s and there are no specific management measures at the 
international level to address fishing mortality in this region. This 
indicates that overutilization may increasingly impact the species over 
the foreseeable future in this region. In the Indian Ocean, 
overutilization will continue to impact the species over the 
foreseeable future. Shortfin mako sharks in the Pacific Ocean are not 
subject to overutilization at this time and there is no indication that 
this will change significantly over the foreseeable future.
    Recreational fishermen target shortfin mako sharks in certain 
regions due to the high quality of their meat and the strong fight 
experienced by the angler. In the U.S. Atlantic, recreational landings 
of shortfin mako sharks have been significantly reduced after 
management measures were implemented in 2018 and 2019. In the Pacific, 
both U.S. and Australian recreational fisheries for the species are 
largely catch-and-release. Further, population-level impacts of 
recreational fishing at a global scale are unlikely to occur due to 
vessel limitations that prevent the vast majority of the ``fleet'' from 
accessing the whole of the species' habitat. For these reasons, the ERA 
Team unanimously concluded that the best available scientific and 
commercial data indicate that recreational fishing is unlikely to 
contribute significantly to the species' risk of extinction now or in 
the foreseeable future as they defined it. We agree that recreational 
fishing is not contributing significantly to the species' risk of 
extinction now. Over the foreseeable future of 50 years that we have 
determined is more appropriate to apply for this species, we also find 
that recreational fishing is not likely to significantly contribute to 
the shortfin mako shark's risk of extinction because there is no basis 
to predict that the impact of recreational fisheries on the species 
will change over the extended time horizon.

Disease and Predation

    Shortfin mako sharks are known to host a number of parasites, but 
the ERA Team found no evidence that disease is impacting the status of 
the species, nor any indication that disease may influence the species' 
status in the foreseeable future.
    The shortfin mako shark is a large apex predator with few natural 
predators. Given current population estimates and distribution, impacts 
from predation on a global scale are not likely to affect the species' 
extinction risk. While climate change may cause changes to the marine 
food web (and therefore, potentially influence predation on juvenile 
shortfin mako sharks) over the next several decades, the ERA Team could 
not accurately predict how these changes may impact the species.
    The ERA Team concluded that the best available scientific and 
commercial information indicates that neither disease nor predation are 
factors that are contributing or will likely contribute significantly 
to the species' extinction risk now or in the foreseeable future as 
they defined it. We agree that neither disease nor predation are 
contributing significantly to the species' extinction risk now. Over 
the foreseeable future of 50 years that we have determined is more 
appropriate to apply for this species, we also find that this factor is 
not likely to significantly contribute to the shortfin mako shark's 
risk of extinction because there is no basis to predict that this 
factor will change over the extended time horizon.

Inadequacy of Existing Regulatory Mechanisms

    The ERA Team evaluated existing regulatory mechanisms to determine 
whether they may be inadequate to address threats to the shortfin mako 
shark from overutilization. Below is a description and evaluation of 
current and relevant domestic and international management measures 
that affect the shortfin mako shark. More detailed information on these 
management measures can be found in the Status Review Report.
U.S. Domestic Regulatory Mechanisms
    The U.S. Secretary of Commerce has the authority to manage highly 
migratory species (HMS) in the U.S. EEZ of the Atlantic Ocean, Gulf of 
Mexico, and Caribbean Sea (16 U.S.C. 1811 and 16 U.S.C. 1854(f)(3)). 
The Atlantic HMS Management Division within NMFS develops regulations 
for Atlantic HMS fisheries and primarily coordinates the management of 
HMS fisheries in federal waters (domestic) and the high seas 
(international), while individual states establish regulations for HMS 
in state waters. However, federally permitted shark fishermen are 
required to follow federal regulations in all waters, including state 
waters, unless the state has more restrictive regulations. For example, 
the Atlantic States Marine Fisheries Commission (ASMFC) developed an 
interstate coastal shark Fisheries Management Plan (FMP) that 
coordinates management measures among all states along the Atlantic 
coast (Florida to Maine) in order to ensure that the states are 
following federal regulations. This interstate shark FMP became 
effective in 2010.
    Shortfin mako sharks in the Atlantic are managed under the pelagic 
species complex of the Consolidated Atlantic HMS FMP. The first 
Atlantic Shark FMP of 1993 classified the status of pelagic sharks as 
unknown because no stock assessment had been conducted for this 
complex. At that time, MSY for pelagic sharks was set at 1,560 t 
dressed weight (dw), which was the 1986-1991 commercial landings 
average for this group. However, as a result of indications that the 
abundance of Atlantic sharks had declined, commercial quotas for 
pelagic sharks were reduced in 1997. The quota for pelagic sharks was 
then set at 580 t. In 1999, the U.S. FMP for Atlantic Tunas, Swordfish, 
and Sharks implemented the following measures affecting pelagic sharks: 
(1) reducing the recreational bag limit to one Atlantic shark per 
vessel per trip, with a minimum size of 137 cm fork length for all 
sharks; (2) increasing the annual commercial quota for pelagic sharks 
to 853 t dw, apportioned between porbeagle (92 t), blue sharks (273 t 
dw), and other pelagic sharks (488 t dw), with the pelagic shark quota 
being reduced by any overharvest in the blue shark quota; and (3) 
making bigeyed sixgill (Hexanchus nakamurai), bluntnose sixgill 
(Hexanchus griseus), broadnose sevengill (Notorynchus cepedianus), 
bigeye thresher, and longfin mako sharks, among other species, 
prohibited species that cannot be retained.
    The management measures for the conservation and management of the 
domestic fisheries for Atlantic swordfish, tunas, sharks, and billfish 
are published in the 2006 Consolidated HMS FMP and implementing 
regulations at 50 CFR part 635 (71 FR 58058, October 2, 2006; NMFS 
2006). Since 2006, this FMP has been amended 12 times, with four 
additional amendments currently under development. Amendment 2, 
finalized in June 2008, requires that all shark fins remain naturally 
attached through landing in both the commercial and recreational 
fisheries (73 FR 35778, June 24, 2008; corrected in 73 FR 40658, July 
15, 2008). Limited exceptions to this requirement allowed by Amendment 
9 (80 FR 73128, November 24, 2015) do not apply to shortfin mako 
sharks.
    Any fisherman who fishes for, retains, possesses, sells, or intends 
to sell, Atlantic pelagic sharks, including shortfin mako sharks, needs 
a Federal Atlantic Directed or Incidental shark limited access permit. 
Generally, directed shark permits (which do not authorize the retention 
of shortfin mako sharks at this time) allow fishermen to target sharks 
while incidental permits

[[Page 68258]]

allow fishermen who normally fish for other species to land a limited 
number of sharks. The permits are administered under a limited access 
program and NMFS is no longer issuing new shark limited access permits. 
To enter the directed or incidental shark fishery, fishermen must 
obtain a permit via transfer from an existing permit holder who is 
leaving the fishery. Until recently, under a directed shark permit, 
there was no numeric retention limit for pelagic sharks, subject to 
quota limitations (see below for a description of a recent final rule 
regarding the retention limit for shortfin mako sharks). An incidental 
permit allows fishermen to keep up to a total of 16 pelagic or small 
coastal sharks (all species combined) per vessel per trip. Authorized 
gear types include: pelagic or bottom longline, gillnet, rod and reel, 
handline, or bandit gear. All fins must remain naturally attached. The 
annual quota for pelagic sharks (other than blue sharks or porbeagle 
sharks) is currently 488.0 t dw (Amendment 2 to the 2006 Consolidated 
Atlantic HMS FMP (73 FR 35778, June 24, 2008; corrected version 73 FR 
40658, July 15, 2008)).
    NMFS monitors the catch of each of the different shark species and 
complexes in relation to its respective annual quota and will close the 
fishing season for each fishery if landings reach, or are projected to 
reach, an 80 percent threshold of the available quota, and are also 
projected to reach 100 percent of the available quota before the end to 
the fishing year. Atlantic sharks and shark fins from federally 
permitted vessels may be sold only to federally permitted dealers; 
however, all sharks must have their fins naturally attached through 
offloading. The head may be removed and the shark may be gutted and 
bled, but the shark cannot be filleted or cut into pieces while onboard 
the vessel. Logbook reporting is required for selected fishermen with a 
federal commercial shark permit. In addition, fishermen may be selected 
to carry an observer onboard, and some fishermen are subject to vessel 
monitoring systems depending on the gear used and locations fished. 
Since 2006, bottom longline and gillnet fishermen fishing for sharks 
have been required to attend workshops to learn how to release sea 
turtles and protected species in a manner that maximizes survival. In 
2017, these workshops were modified to include a section on releasing 
prohibited shark species. Additionally, NMFS published a final rule on 
February 7, 2007 (72 FR 5633), that requires participants in the 
Atlantic shark bottom longline fishery to possess, maintain, and 
utilize handling and release equipment for the release of sea turtles, 
other protected species, and prohibited shark species. In an effort to 
reduce bycatch, NMFS has also implemented a number of time/area 
closures with restricted access to fishermen with HMS permits who have 
pelagic longline gear onboard their vessel.
    The HMS Management Division also published an amendment to the 2006 
Consolidated HMS FMP that specifically addresses Atlantic HMS fishery 
management measures in the U.S. Caribbean territories (77 FR 59842, 
October 1, 2012). Due to substantial differences between some segments 
of the U.S. Caribbean HMS fisheries and the HMS fisheries that occur 
off the mainland of the United States (including permit possession, 
vessel size, availability of processing and cold storage facilities, 
trip lengths, profit margins, and local consumption of catches), the 
HMS Management Division implemented measures to better manage the 
traditional small-scale commercial HMS fishing fleet in the U.S. 
Caribbean Region. Among other things, this rule created an HMS 
Commercial Caribbean Small Boat (CCSB) permit, which: allows fishing 
for and sales of big-eye, albacore, yellowfin, and skipjack tunas, 
Atlantic swordfish, and Atlantic sharks within local U.S. Caribbean 
market; collects HMS landings data through existing territorial 
government programs; authorizes specific gears; is restricted to 
vessels less than or equal to 45 feet (13.7 m) length overall; and may 
not be held in combination with any other Atlantic HMS vessel permits. 
Until 2021, fishermen who held the CCSB permit were prohibited from 
retaining any Atlantic sharks. However, at this time, fishermen who 
hold the CCSB permit are prohibited from retaining shortfin mako 
sharks, and are restricted to fishing for authorized sharks with only 
rod and reel, handline, and bandit gear. Both the CCSB and Atlantic HMS 
regulations have helped protect shortfin mako sharks while in the 
Northwest Atlantic Ocean, Gulf of Mexico, and Caribbean Sea through 
permitting, monitoring, quotas, and retention restrictions.
    After the 2017 ICCAT stock assessment indicated that North Atlantic 
shortfin mako sharks were overfished and experiencing overfishing, the 
United States took action to end overfishing and take steps toward 
rebuilding the stock through emergency rulemaking in March 2018. The 
measures immediately required release of all live shortfin mako sharks 
caught by commercial pelagic longliners with a minimum of harm while 
giving due consideration to the safety of crew members, and only 
allowed retention in pelagic longline gear if the shortfin mako shark 
was dead at haulback. The measures required commercial fishermen using 
non-pelagic longline gear (e.g., bottom longline, gillnet, handgear) to 
release all shortfin mako sharks, alive or dead, with a minimum of harm 
while giving due consideration to the safety of crew members. For 
recreational fisheries, the emergency rulemaking increased the minimum 
size limit for both male and female shortfin mako sharks to 83 inches 
FL. These temporary measures were replaced by long-term management 
measures finalized as Amendment 11 to the 2006 Consolidated HMS FMP in 
March 2019. The final management measures for commercial fisheries 
allowed retention of shortfin mako sharks caught with longline or 
gillnet gears if sharks were dead at haulback. Further, vessels with 
pelagic longline gear were required to have a functional electronic 
monitoring system to verify condition for compliance purposes. For 
recreational fisheries, the minimum size limit was increased from 54 
inches to 71 inches FL for males and 83 inches FL for females, and the 
use of circle hooks was required for all recreational shark fishing. 
These measures led to the reduction of the United States' total 
landings of North Atlantic shortfin mako shark (commercial and 
recreational) from 302 t in 2017, to 165 t in 2018, to 57 t in 2019, 
with 2 t of dead discards, an 81 percent reduction from 2017. In 2020, 
U.S. recreational landings of North Atlantic shortfin mako shark were 
24 t, reduced by over 90 percent from the 2013-2017 average.
    Following the adoption of Recommendation 21-09 at the November 2021 
ICCAT annual meeting (described further below), NMFS published a final 
rule to implement a flexible shortfin mako shark retention limit with a 
default limit of zero in all commercial and recreational HMS fisheries 
(87 FR 39373; July 1, 2022). The rule meets domestic management 
objectives, implements Recommendation 21-09, and acknowledges the 
possibility of future retention (limited retention of shortfin mako 
sharks may be allowed in 2023 and future years if ICCAT determines that 
fishing mortality is at a low enough level North Atlantic-wide to allow 
retention consistent with the conservation objectives of the 
recommendation). The rule, effective July 5, 2022, requires that all 
commercial and recreational fishermen

[[Page 68259]]

release all shortfin mako sharks, whether dead or alive, at haulback. 
Any sharks released alive must be released promptly in a manner that 
causes the least harm to the shark.
    In the U.S. Pacific, HMS fishery management is the responsibility 
of adjacent states and three regional management councils that were 
established by the Magnuson-Stevens Fishery Conservation and Management 
Act (MSA): the Pacific Fishery Management Council (PFMC), the North 
Pacific Fishery Management Council (NPFMC), and the Western Pacific 
Regional Fishery Management Council (WPRFMC). Based on the range of the 
shortfin mako shark, only the PFMC and WPRFMC directly manage the 
species.
    The PFMC's area of jurisdiction is the EEZ off the coasts of 
California, Oregon, and Washington. Prior to the development of a West 
Coast-based FMP for HMS, the fisheries were managed by the states of 
California, Oregon, and Washington, although some federal laws also 
applied. In late October 2002, the PFMC adopted its FMP for U.S. West 
Coast HMS Fisheries. This FMP's management area also covers adjacent 
high seas waters for fishing activity under the jurisdiction of the HMS 
FMP. The final rule implementing the HMS FMP was published in the 
Federal Register on April 7, 2004 (69 FR 18443). Since its 
implementation, this FMP has been amended five times, most recently in 
2018. The FMP requires a federal permit for all commercial HMS vessels 
that fish for HMS off of California, Oregon or Washington, or land HMS 
in these states. The permit is endorsed with a specific endorsement for 
each gear type to be used, and any commercial fisher may obtain the 
required gear endorsements. Legal HMS gear includes harpoon, surface 
hook and line, large mesh drift gillnet, purse seine, and pelagic 
longline; however, the use of these gears are subject to state 
regulatory measures. For commercial passenger recreational fishing 
vessels, a federal permit is required by the FMP, though existing state 
permits or licenses for recreational vessels can meet this requirement. 
Legal recreational gear includes rod-and-reel, spear, and hook and 
line. Per the FMP, due to the stock's vulnerability, possible 
importance of the U.S. West Coast EEZ as nursery habitat, and poorly 
known total catches and extent of the stock, the recommended harvest 
guideline for shortfin mako sharks is 150 t round weight. This harvest 
guideline is a general objective, not a quota. Although attainment of a 
harvest guideline doesn't require management action such as closure of 
the fishery, it does prompt a review of the fishery.
    The WPRFMC's area of jurisdiction is the EEZs of Hawaii, 
Territories of American Samoa and Guam, Commonwealth of the Northern 
Mariana Islands, and the Pacific Remote Island Areas, as well as the 
domestic fisheries that occur on the adjacent high seas. The WPRFMC 
developed the Fishery Ecosystem Plan for Pacific Pelagic Fisheries of 
the Western Pacific Region (FEP; formerly the Fishery Management Plan 
for the Pelagic Fisheries of the Western Pacific Region) in 1986 and 
NMFS, on behalf of the U.S. Secretary of Commerce, approved the Plan in 
1987. Since that time, the WPRFMC has recommended, and NMFS has 
approved, numerous amendments to the Plan as necessary for conservation 
and management purposes. The WPRFMC manages HMS fisheries pursuant to 
the FEP, and species that are managed under FMPs or FEPs are called 
Management Unit Species (MUS), and typically include those species that 
are caught in quantities sufficient to warrant management or specific 
monitoring by NMFS and the Council. In the FEP, shortfin mako sharks 
are designated as a Pelagic MUS and, thus, are subject to regulations 
under the FEP. These regulations are intended to minimize impacts to 
targeted stocks as well as protected species. Fishery data are also 
analyzed in annual reports and used to amend the FEP as necessary.
    In addition to fishing regulations for highly migratory species, 
the United States has implemented several significant laws for the 
conservation and management of sharks. The Tuna Conventions Act of 
1950, Atlantic Tunas Convention Act of 1975, and Western and Central 
Pacific Fisheries Convention Implementation Act (enacted in 2007) 
authorize the U.S. Secretary of Commerce to promulgate regulations for 
U.S. vessels that fish for tuna or tuna-like species in the IATTC, 
ICCAT, and WCPFC Convention areas, respectively. The MSA, originally 
enacted in 1976, is the primary law governing marine fisheries 
management in U.S. federal waters (3-200 miles offshore), and aims to 
prevent overfishing, rebuild overfished stocks, increase long-term 
economic and social benefits, and ensure a safe and sustainable supply 
of seafood. The MSA created eight regional fishery management councils, 
whose main responsibility is the development and subsequent amendment 
of FMPs for managed stocks. The MSA requires NMFS to allocate both 
overfishing restrictions and recovery benefits fairly and equitably 
among sectors of the fishery. In the case of an overfished stock, NMFS 
must establish a rebuilding plan through an FMP or amendment to such a 
plan. The FMP or amendment to such a plan must specify a time period 
for ending overfishing and rebuilding the fishery that shall be as 
short as possible, taking into account the status and biology of the 
stock, the needs of fishing communities, recommendations by 
international organizations in which the United States participates, 
and the interaction of the overfished stock within the marine 
ecosystem. The rebuilding plan cannot exceed ten years, except in cases 
where the biology of the stock, other environmental conditions, or 
management measures under an international agreement in which the 
United States participates dictate otherwise.
    The Shark Finning Prohibition Act of 2000 prohibits any person 
under U.S. jurisdiction from: (i) engaging in the finning of sharks; 
(ii) possessing shark fins aboard a fishing vessel without the 
corresponding carcass; and (iii) landing shark fins without the 
corresponding carcass, among other things. The Shark Conservation Act 
of 2010 strengthened shark finning measures by prohibiting any person 
from removing shark fins at sea (with a limited exception for smooth 
dogfish, Mustelus canis); or possessing, transferring, or landing shark 
fins unless they are naturally attached to the corresponding carcass.
    Management measures implemented in response to the status of the 
North Atlantic shortfin mako shark stock were finalized in March 2019, 
and have been effective in reducing U.S. landings of the species in 
this region (both recreationally and commercially) as previously 
discussed. NMFS recently published a final rule to implement ICCAT 
Recommendation 21-09, requiring that all U.S. commercial and 
recreational fishermen release all shortfin mako sharks, whether dead 
or alive, at haulback. The adequacy of this retention prohibition 
cannot be assessed at this time; as data for each fishing year is not 
reported until the following calendar year, the effect of this measure 
will not be easily assessed until 2024 when the landings and discard 
data from 2023 can be analyzed. In the Pacific, the available stock 
assessment for the North Pacific region indicates that the species is 
neither overfished nor experiencing overfishing (ISC Shark Working 
Group 2018). For the foregoing reasons, it is likely that U.S. domestic 
fisheries management measures are adequate to address threats of 
overfishing to the species in U.S. waters. With regard to the fin and 
meat trade, declines in U.S. exports of shark fins

[[Page 68260]]

followed implementation of both the Shark Finning Prohibition Act and 
the Shark Conservation Act, and recent declines in the mean value of 
U.S. exports per metric ton have been reported by NMFS. Additionally, 
14 U.S. states and three U.S. territories have enacted legislation 
controlling shark finning by banning possession and sale of shark fins 
(see details in the Status Review Report). These state laws have 
reduced U.S. landings of sharks and therefore U.S. trade and 
consumption of shark fins, although it is important to note that the 
United States has traditionally played a relatively minimal role in the 
global shark fin trade (0.3 and 0.4 percent of global imports and 
exports in U.S. dollars according to Ferretti et al. 2020). Measures 
that prohibit the possession and sale of shark fins may provide some 
limited conservation benefit to sharks, including the shortfin mako 
shark, by discouraging the landing of any sharks. The ERA Team 
therefore concluded that the best available scientific and commercial 
data indicate that U.S. domestic regulatory measures are adequate to 
manage impacts from fisheries on the species in U.S. waters, as 
evidenced by the reduction in U.S. shortfin mako shark catch 
(commercial and recreational) in the Atlantic following the 2017 ICCAT 
stock assessment, stable population status in the North Pacific, and 
strong prohibitions on shark finning for those subject to U.S. 
jurisdiction. We agree with their assessment.
International Regulatory Mechanisms
    Despite adequate management in U.S. waters, the ERA Team concluded 
that regulatory measures to address threats of incidental catch, 
targeted catch (in certain limited areas and fleets), and trade across 
the species' range may not be adequate in certain regions.
    RFMOs that manage HMS play perhaps the most significant role in 
regulating catch and mortality of shortfin mako sharks in commercial 
fisheries worldwide. Of the four major RFMOs that manage shortfin mako 
sharks, only ICCAT has management measures specific to the species, 
while IATTC, WCPFC, and IOTC have general shark management measures.
    ICCAT is the main international regulatory body for managing 
shortfin mako sharks on the high seas in the Atlantic Ocean. In 2004, 
following the development and implementation of the International Plans 
of Action for Conservation and Management of Sharks (IPOA-Sharks), 
ICCAT adopted Recommendation 04-10 requiring CPCs to annually report 
data for catches of sharks, including available historical data. This 
Recommendation specifically called for the SCRS to review the 
assessment of shortfin mako sharks and recommend management 
alternatives for consideration by the Commission, and to reassess the 
species no later than 2007. In 2005, ICCAT adopted Recommendation 05-
05, which amended Recommendation 04-10 by requiring CPCs to annually 
report on their implementation of the Recommendation, and instructing 
those that have not yet implemented this recommendation to reduce North 
Atlantic shortfin mako shark mortality to implement it and report to 
the Commission. In 2006, ICCAT adopted Recommendation 06-10, which 
further amended Recommendation 04-10 and called for a shortfin mako 
shark stock assessment in 2008. A supplemental Recommendation by ICCAT 
(07-06, adopted in 2007 and entered into force in 2008) called for CPCs 
to submit catch data including estimates of dead discards and size 
frequencies in advance of SCRS assessments, to take appropriate 
measures to reduce fishing mortality for the North Atlantic shortfin 
mako shark, and to implement research on pelagic sharks in the 
Convention area to identify potential nursery areas. Recommendation 10-
06 (adopted in 2010 and entered into force in 2011) instructed CPCs to 
report on how they have implemented the three recommendations described 
above, particularly steps they have taken to improve data collection 
for direct and incidental catches. It also recommended that CPCs that 
do not report catch data for shortfin mako sharks be prohibited from 
retaining the species, and that the SCRS conduct a stock assessment for 
shortfin mako sharks in 2012. Recommendation 14-06 (adopted in 2014 and 
entered into force in 2015) replaced and repealed Recommendations 05-05 
and 10-06, among others, and it calls for CPCs to improve data 
collection for shortfin mako shark and report information on domestic 
catch of shortfin mako shark to ICCAT and encourages CPCs to undertake 
research on biology and life history of the shortfin mako shark.
    Based on the 2017 shortfin mako shark stock assessment, which 
concluded there was a 90 percent probability of the stock being in an 
overfished state and experiencing overfishing (as discussed previously 
in Abundance and Trends), the Commission adopted Recommendation 17-08 
(adopted in 2017 and entered into force in 2018), requiring CPCs to 
release North Atlantic shortfin mako sharks in a manner that causes the 
least harm. Retention of dead North Atlantic shortfin mako sharks 
remained acceptable in many cases, and harvest of live shortfin was 
only permitted under very limited circumstances. In 2019, the SCRS 
carried out new projections for North Atlantic shortfin mako shark 
through 2070 (two generation lengths) at the Commission's request 
(projections are described above in Abundance and Trends). Multiple TAC 
options with associated time frames and probabilities of rebuilding 
were presented to the Commission. Based on the resulting negative 
projections and high susceptibility of the species to overexploitation, 
and to accelerate the rate of recovery and to increase the probability 
of success, the SCRS recommended that the Commission adopt a non-
retention policy without exception. While a non-retention policy would 
ostensibly reduce mortality, shortfin mako sharks frequently interact 
with surface longline fisheries and the potential inability for 
fishermen to avoid the species may not lead to sufficient decreases in 
mortality. Therefore, the SCRS noted that other management measures, 
such as time-area closures, reduction of soak time, safe handling, and 
best release practices may also be required (ICCAT 2019).
    In 2019, several countries presented proposals to end overfishing 
and rebuild the North Atlantic stock of shortfin mako shark; however, 
none were ultimately adopted (see Status Review Report for more 
detail). The United States, Senegal, Canada, the EU, and Morocco met 
several times to discuss the proposals, but were unable to reach 
agreement on the elements of a combined measure. In a proposal 
presented by the ICCAT Chair and adopted in 2019 (Recommendation 19-
06), it was agreed to extend and update the existing provisions in 
Recommendation 17-08. Recommendation 19-06 also urged the Commission to 
adopt a new management recommendation for the North Atlantic shortfin 
mako shark at its 2020 annual meeting in order to establish a 
rebuilding plan with a high probability of avoiding overfishing and 
rebuilding the stock to BMSY within a timeframe that takes 
into account the biology of the stock. Due to the COVID-19 pandemic, 
however, ICCAT did not host an annual meeting in 2020 and management 
decisions were made through a correspondence process. Due to the 
difficulty associated with this process, no consensus could be made on 
a new measure and Recommendation 19-06 remained in place.

[[Page 68261]]

    In 2021, the ICCAT annual meeting was conducted virtually and the 
conservation of the North Atlantic shortfin mako shark stock was a 
priority. Commission members reached consensus on Recommendation 21-09, 
which puts into place a 2-year retention ban that aims to reduce 
mortality and establishes a process to evaluate if and when retention 
may be allowed in the future, in line with scientific advice. The 
measure contains strong provisions to improve data reporting, and 
particularly, the catch reporting of live releases and fish discarded 
dead, by all ICCAT parties. This measure entered into force on June 17, 
2022, and as data for each fishing year is not reported until the 
following calendar year, the management effect of Recommendation 21-09 
will not be easily assessed until 2024 when the landings and discard 
data from 2023 can be analyzed. Despite this important step forward, 
ICCAT's work to end overfishing and rebuild North Atlantic shortfin 
mako shark is not complete; within Recommendation 21-09 a provision 
exists to revisit the measure ``no later than 2024 to consider 
additional measures to reduce total fishing mortality.'' Future efforts 
will likely be focused on reducing the at-haulback and post-release 
mortality of North Atlantic shortfin mako shark unintentionally 
captured alongside target species.
    The low productivity of the shortfin mako shark means that the 
biological response to the recently adopted ICCAT measure will likely 
not be detectable for many years, despite assessment efforts. 
Therefore, at this time it is not possible to assess the adequacy of 
this measure to address the ongoing threat of overfishing in the North 
Atlantic. The ERA Team raised some concerns and uncertainties with 
regard to Recommendation 21-09. The measure does not require changes to 
fishing behavior or gear, and therefore will not address at-vessel or 
post-release mortality of incidentally caught shortfin mako sharks. 
Based on recent reported landings allowed under Recommendation 19-06 
indicating high numbers of shortfin mako sharks dead at-haulback, it is 
unclear if Recommendation 21-09 will reduce mortality to a point that 
will allow the North Atlantic stock to rebuild. It is also unclear what 
measures will be in place after the 2-year period ends.
    The IATTC is responsible for the conservation and management of 
tuna and other pelagic species in the Eastern Pacific. There are 
currently no specific resolutions related to the management of shortfin 
mako shark; however, IATTC does have resolutions relating to sharks in 
general. Resolution C-16-05 on the management of shark species requires 
that purse-seine vessels promptly release any shark that is not 
retained as soon as it is seen in the net or on deck, and includes 
provisions for safe release of such sharks. Resolution C-05-03 requires 
that fins onboard vessels total no more than 5 percent of the weight of 
sharks onboard. The IATTC requires 100 percent observer coverage 
onboard the largest purse seine vessels, and 5 percent observer 
coverage on larger longline vessels.
    The WCPFC is responsible for the conservation and management of 
highly migratory species in the Western and Central Pacific Ocean. The 
WCPFC aims to address issues related to the management of high seas 
fisheries resulting from unregulated fishing, over-capitalization, 
excessive fleet capacity, vessel re-flagging to escape controls, 
insufficiently selective gear, unreliable databases, and insufficient 
multilateral cooperation with respect to conservation and management of 
highly migratory fish stocks. There are currently no management 
measures specific to shortfin mako sharks in the WCPFC; however, their 
management is addressed under the Conservation and Management Measure 
for Sharks (CMM 2019-04). This measure prohibits finning, requires that 
vessels land sharks with their fins naturally attached, and calls for 
vessels to reduce bycatch and practice safe release of sharks. In order 
to reduce bycatch mortality, the measure calls for longline fisheries 
targeting billfish and tuna to either not use wire branch lines or 
leaders, or not use shark lines (branch lines running directly off 
longline floats or drop lines). Further, the measure requires catches 
of key shark species to be reported to the Commission annually.
    In Indian Ocean waters, the IOTC serves to promote cooperation 
among CPCs to ensure, through appropriate management, the conservation 
and optimum utilization of stocks, and encourage sustainable 
development of fisheries based on such stocks. The United States is not 
a member. Conservation and management measures are adopted in the form 
of either resolutions, which require a two-thirds majority of Members 
present and voting to adopt them and are binding for contracting 
parties, or recommendations, which are non-binding and rely on 
voluntary implementation. While a number of measures have been adopted 
by IOTC parties that apply to sharks and bycatch in general, there are 
currently no specific resolutions related to the management of shortfin 
mako shark (see IOTC 2019). In Resolution 15/01 on the recording of 
catch and effort by fishing vessels in the IOTC area of competence, all 
purse seine, longline, gillnet, pole and line, handline, and trolling 
fishing vessels are required to have a data recording system and 
provide aggregated data to the Secretariat each year. Resolution 15/02 
mandates statistical reporting requirements for IOTC CPCs by species 
and gear for all species under the IOTC mandate as well as the most 
commonly caught elasmobranch species and lays out requirements for 
observer coverage. IOTC Resolution 17/05 on the conservation of sharks 
caught in association with fisheries managed by IOTC requires that 
sharks landed fresh not have their fins removed prior to first landing, 
and for sharks landed frozen, CPCs must abide by the 5 percent fins-to-
carcass weight ratio. Further, CPCs must report data for catches of 
sharks including all available historical data, estimates and life 
status of discards (dead or alive), and size frequencies under this 
resolution. Despite these requirements, reporting of shark catches has 
been very irregular and information on shark catch and bycatch is 
considered highly incomplete (Murua et al. 2018). A number of countries 
continue to not report on their interactions with bycatch species as 
evidenced by high rates of bycatch reported by other fleets using 
similar gear configurations (IOTC 2018). The lack of reliable records 
of catch and lack of a formal stock assessment make it difficult to 
determine whether the regulatory mechanisms described above are 
adequate to address overutilization of the species in the Indian Ocean.
    Regarding the general shark conservation measures in place for 
WCPFC, IATTC, and IOTC, the ERA Team had concerns regarding low 
compliance with reporting requirements, especially in the Indian Ocean 
and South Atlantic Ocean. The lack of reliable catch data in these 
regions, as well as a lack of formal stock assessments in the Indian 
Ocean and South Pacific Ocean, make it difficult to assess whether 
regulatory mechanisms in these areas are adequate to address threats of 
overutilization to the species.
    As the shortfin mako shark is highly valued for both its meat and 
fins, regulatory mechanisms ensuring that trade does not lead to 
overexploitation are critical to the species' survival. Many individual 
countries and RFMOs have implemented measures to curb the practice of 
shark finning and the sale of or trade in shark products over the last 
decade (see detailed information in the Status Review Report), and the 
shortfin

[[Page 68262]]

mako shark was listed on Appendix II of CITES as of November 2019. 
CITES is an international convention that aims to ensure that 
international trade in animals and plants does not threaten their 
survival, and while CITES regulates international trade, it does not 
regulate take or trade within a country. Appendix II includes species 
not necessarily threatened with extinction, but trade must be 
controlled to ensure utilization is compatible with their survival. As 
an Appendix II-listed species, international trade in specimens of 
shortfin mako shark is allowed with an export permit, re-export 
certificate, or introduction from the sea certificate granted by the 
proper management authority. The above permits or certificates may be 
granted if the trade is found to be non-detrimental to the survival of 
the species in the wild and the specimen was found to have been legally 
acquired. A number of countries have taken a reservation to the listing 
(Botswana, Democratic Republic of the Congo, Eswatini, Japan, Namibia, 
Norway, South Africa, United Republic of Tanzania, Zambia, and 
Zimbabwe) meaning they have made a unilateral decision to not be bound 
by the provisions of CITES relating to trade in this species.
    Although the CITES listing is a positive step to ensure the 
sustainability of the international trade of shortfin mako sharks, it 
is difficult to assess the effectiveness of this measure over such a 
short period of time. An analysis of trade data and fin trimmings from 
a Hong Kong market led Carde[ntilde]osa et al. (2018) to conclude that 
compliance with reporting and permitting requirements for CITES-listed 
shark species listed at the 16th CITES Conference of the Parties (2013) 
was low in 2015-2016. Therefore, the CITES listing of shortfin mako 
shark may not have a strong impact on the number of individuals 
harvested for the international fin and meat trades. While the fin 
trade has declined, recent increases in the trade of shark meat signify 
the continued need for regulatory mechanisms to address the threat of 
overutilization in the international fin and meat trades.
    Overall, while the ERA Team recognized the strong regulatory 
measures in place for shortfin mako sharks in U.S. domestic waters, 
retention bans that have been put in place for the species in several 
countries and recently by ICCAT, and increased global efforts to end 
shark finning, the ERA Team expressed concern about the adequacy of 
existing regulatory mechanisms to monitor and manage mortality from 
fisheries interactions on the high seas and the international meat and 
fin trade. The ERA Team was split on how this factor contributes to the 
extinction risk of the species, with just over half of the group 
concluding that the inadequacy of existing regulatory mechanisms will 
likely contribute significantly to the species' risk of extinction in 
the foreseeable future as they defined it, but is not likely 
contributing to the species' extinction risk currently. The remaining 
members found it unlikely that this factor is significantly 
contributing to the species' extinction risk now or would do so in the 
foreseeable future as they defined it. We agree with the ERA Team's 
assessment that the inadequacy of existing regulatory mechanisms is not 
likely contributing to the species' risk of extinction currently. Over 
the foreseeable future of 50 years that we have determined is more 
appropriate to apply for this species, we find that existing regulatory 
mechanisms may be inadequate to address overutilization, especially 
given the species' low productivity and prevalence in both meat and fin 
markets.

Other Natural or Manmade Factors Affecting Its Continued Existence

    Under this factor, the ERA Team considered potential threats posed 
by pollutants and environmental contaminants, climate change, and shark 
control/bather protection efforts.
    As high-level predators, shortfin mako sharks bioaccumulate and 
biomagnify heavy metals and organic contaminants; however, the impacts 
of these pollutants on the physiology and productivity of the species 
(and sharks in general) are poorly studied. While results of few 
available studies of other species of sharks and fish provide some 
evidence that sharks may experience negative physiological impacts and 
potentially reduced fitness as a result of contaminant exposure, the 
ERA Team found no evidence that individuals or populations are 
adversely affected to a degree that would impact the status of the 
species. Therefore, the ERA Team unanimously agreed that pollutants and 
environmental contaminants are unlikely to be contributing 
significantly to the species' extinction risk now or in the foreseeable 
future as they defined it. We agree that pollutants and environmental 
contaminants are not likely contributing significantly to the species' 
extinction risk now. Over the foreseeable future of 50 years that we 
have determined is more appropriate to apply for this species, we find 
that pollutants and environmental contaminants are not likely to 
significantly contribute to the shortfin mako shark's risk of 
extinction because this factor is not currently negatively affecting 
the species' status and the best available scientific and commercial 
data suggests no basis to predict that this will change over the 
extended time horizon.
    When considering the potential threat of climate change to the 
shortfin mako shark, the ERA Team considered projected impacts to the 
marine environment (including warming waters, acidification, and 
shifting habitat suitability and prey distributions), and the species' 
potential responses to these impacts. While long-term climate 
projections (through 2100) are available and considered reliable, the 
ERA Team found that the species' responses to these projected 
environmental changes that far into the future could not be predicted 
with any certainty. While some studies predict that the species may be 
subject to significant habitat loss and potential behavioral and 
fitness impairments by 2100, the shortfin mako shark's broad prey base 
and thermal tolerance, among other factors, may give them a high 
adaptive capacity. A detailed review of available studies can be found 
in the Status Review Report. The majority of the ERA Team considered it 
unlikely that climate change is currently contributing to the species' 
extinction risk, or will contribute to the species' extinction risk in 
the foreseeable future as they defined it. Several ERA Team members 
concluded that the contribution of climate change to the extinction 
risk of the species in the foreseeable future could not be determined 
due to the lack of available information on the species' response to 
climate change. We agree that the best available scientific and 
commercial information indicates that climate change is not 
significantly contributing to the species' extinction risk now. Over 
the foreseeable future of 50 years that we have determined to be more 
appropriate to apply for this species, we also find that climate change 
is not likely to significantly contribute to the shortfin mako shark's 
risk of extinction because it is not currently negatively affecting the 
species' status and the best available scientific and commercial data 
suggests no basis to predict that this will change over the extended 
time horizon.
    A small number of shortfin mako sharks experience mortality as a 
result of shark control/bather protection programs in South Africa and 
Australia, which aim to reduce the risk of shark attacks on humans near 
public beaches. Due to the localized geographic extent of the programs 
and the very low number of individuals impacted, the ERA Team did not 
find that shark control programs are likely contributing

[[Page 68263]]

to the extinction risk of the species now, and found it unlikely that 
these programs would contribute significantly to extinction risk in the 
foreseeable future as they defined it. We agree that the best available 
scientific and commercial information indicates that these programs are 
not likely contributing significantly to the species' extinction risk 
now. Over the foreseeable future of 50 years that we have determined to 
be more appropriate to apply for this species, we also find that bather 
protection nets are not likely to significantly contribute to the 
shortfin mako shark's risk of extinction because they are not currently 
negatively affecting the species' status and the best available 
scientific and commercial information suggests no basis to predict that 
this will change over the extended time horizon.
    In sum, the ERA Team did not identify any other natural or manmade 
factors affecting the continued existence of the shortfin mako shark, 
and we agree with their assessment.

Synergistic Impacts

    We considered whether the impacts from threats described here and 
in the Status Review Report may cumulatively or synergistically affect 
the shortfin mako shark beyond the scope of each individual stressor. 
As discussed previously, overutilization has resulted in historical 
declines across the species' range and is expected to continue to 
affect the species in certain regions over the foreseeable future. The 
impact of overutilization on the species increases when regulatory 
mechanisms to address this threat are inadequate. The species' low 
productivity means that it will take longer to rebuild a stock if it 
becomes depleted due to overutilization. While there is no evidence 
that range contractions have occurred, or that destruction or 
modification of shortfin mako shark habitat on a global scale has 
occurred to such a point that it has impacted the status of the species 
or is likely to in the foreseeable future, climate change has the 
potential to alter the distribution of prey species and suitable 
habitat that may result in changes in distribution. This may in turn 
impact the frequency of fisheries interactions and resulting fishing 
mortality. Further, climate change-induced shifts in the marine food 
web have the potential to influence predation on juvenile shortfin mako 
sharks over the next several decades. We cannot reasonably predict 
either of these changes and their effects on the shortfin mako shark 
based on the best available scientific and commercial information. 
While some studies project that the species may be subject to 
significant habitat loss by 2100, the shortfin mako shark's broad prey 
base and thermal tolerance, among other factors, may give them a high 
adaptive capacity (see the Status Review Report). The specific impacts 
that climate change will have on the species, and how the species might 
be able to adapt to changing oceanic conditions, is unknown. Therefore, 
while we considered these potential synergistic effects, we conclude 
that the best available scientific and commercial information indicates 
that climate change is not likely to act synergistically with other 
threats to increase the extinction risk of the shortfin mako shark now 
or in the foreseeable future.

Extinction Risk Determination

    Guided by the results and discussions from the demographic risk 
analysis and ESA Section 4(a)(1) factor assessment, the ERA Team 
analyzed the overall risk of extinction to the global shortfin mako 
shark population. In this process, the ERA Team considered the best 
available scientific and commercial information regarding the shortfin 
mako shark from all regions of the species' global range, and analyzed 
the collective condition of these populations to assess the species' 
global extinction risk. The ERA Team was fairly confident in 
determining the overall extinction risk of the species, placing two-
thirds of their likelihood points in the low risk category. Some 
uncertainty was reflected in the allocation of points to the moderate 
risk category, largely due to poor reporting of catches and low 
confidence in abundance and trends in certain regions. No points were 
allocated to the high risk category (see definitions of risk categories 
in Methods).
    The ERA Team acknowledged that the shortfin mako shark has 
experienced historical declines of varying degrees in all ocean basins, 
mainly due to interactions with commercial fishing vessels, however, 
current abundance trends are mixed. A robust recent stock assessment in 
the North Pacific indicates that the species is stable and potentially 
increasing there, and population increases are also indicated in the 
South Pacific. In other words, across the entire Pacific Ocean basin, 
the species is either stable and/or potentially increasing. The recent 
stock assessment in the North Atlantic, which the ERA Team also 
considered highly reliable, indicates ongoing declines that will 
continue into the foreseeable future. However, the ERA Team concluded 
that this region is not at risk of extirpation based on available 
projections carried out by ICCAT's SCRS, information on current 
fisheries mortality, and predictions about future management and levels 
of fisheries mortality. The South Atlantic may also have a declining 
population trend, but this is highly uncertain. Fisheries mortality 
remains high in the region. In the Indian Ocean, preliminary stock 
assessments indicate that the shortfin mako shark population is 
experiencing overfishing but is not overfished, and increasing CPUE 
trends are indicated in several key fisheries in this region. 
Compliance with reporting requirements is quite low in this region, 
however, so the ERA Team felt that the extent of the species' decline 
in this region is highly uncertain and potentially underestimated. Even 
with continued declines in the North Atlantic and likely population 
declines of uncertain degrees in the South Atlantic and Indian Oceans, 
the stable and potentially increasing population status in the Pacific 
Ocean, a major segment of the global population, led the majority of 
the ERA Team to conclude that abundance would not contribute 
significantly to the extinction risk of the species now or in the 
foreseeable future. The ERA Team also concluded that the shortfin mako 
shark's high genetic and ecological diversity, connectivity between 
populations, and wide spatial distribution reduce the species' 
extinction risk by providing resilience in the face of stochastic 
events and threats concentrated in certain regions. The ERA Team did, 
however, find that the low productivity of the species would likely 
contribute significantly to the species' risk of extinction in the 
foreseeable future as the species is highly susceptible to depletion 
from exploitation, and will recover slowly from such declines.
    Overutilization in commercial fisheries and inadequate regulatory 
mechanisms to manage these fisheries are the main drivers of observed 
population declines. While regulatory mechanisms have recently been 
adopted to at least temporarily prohibit retention of the species in 
the North Atlantic and to ensure the sustainability of the 
international trade in shortfin mako shark products, it is too soon to 
accurately assess the adequacy of these measures to address 
overutilization. The ERA Team did consider the lack of compliance with 
reporting requirements in the Indian Ocean and South Atlantic Ocean 
concerning for the species, especially considering the high value of 
the species in the meat and fin trade. The low confidence in catch data 
also made it difficult for the ERA Team to assess whether regulatory 
mechanisms

[[Page 68264]]

are inadequate to address the threat of overutilization in these 
regions.
    Overall, the ERA Team concluded that the species is not at high or 
moderate risk of extinction based on the following: (1) the high 
adaptability of the species based on its use of multiple habitat types, 
tolerance of a wide range of water temperatures, and generalist diet; 
(2) the existence of genetically and ecologically diverse, sufficiently 
well-connected populations; (3) the species' wide spatial distribution 
with no indication of range contractions or extirpations in any region, 
even in areas where there is heavy bycatch mortality and utilization of 
the species' high-value fins and meat; (4) the stable and potentially 
increasing population trend indicated in the Pacific Ocean, a major 
segment of the species' range; (5) abundance estimates of one million 
and eight million individuals in the North Atlantic and North Pacific, 
respectively; and (6) no indication that the species is experiencing 
depensatory processes due to low abundance. Based on all of the 
foregoing information, which represents the best scientific and 
commercial data available regarding current demographic risks and 
threats to the species, the ERA Team concluded that the shortfin 
currently has a low risk of extinction rangewide.
    We agree with the ERA Team's assessment that the shortfin mako 
shark is not at high risk of extinction rangewide for the above 
reasons. Extending the foreseeable future to 50 years (two generation 
lengths), as we have determined is more appropriate to apply for this 
species, does not alter this conclusion and, for the reasons summarized 
here, we continue to find that the species is at low risk of extinction 
throughout its range. In the North Atlantic, the population is 
estimated to have experienced declines in total biomass of 47-60 
percent and declines in SSF of 50 percent from 1950 to 2015 (ICCAT 
2017). Since then, levels of fishing mortality in the North Atlantic 
have declined in response to management measures implemented in recent 
years (3,281 t in 2015; 3,356 t in 2016; 3,199 t in 2017; 2,373 t in 
2018; 1,882 t in 2019; 1,709 t in 2020) (SCRS 2021). While we recognize 
that current levels of mortality (1,709 t in 2020) are higher than any 
of the TAC levels examined in the projections carried out by the SCRS 
(up to 1,100 t inclusive of dead discards, ICCAT 2019), over the next 
50 years, recently adopted retention prohibitions and increasing 
international efforts to reduce the effects of fishing mortality on the 
species in this region will likely result in further decreases in 
fishing mortality in this region (although we are unable to conclude 
the magnitude of potential declines, or whether they will be large 
enough to rebuild the stock). Therefore, the best available scientific 
and commercial information supports our forecast that the rate of 
decline will likely slow compared to the 1950-2015 time period. 
Although the stock is expected to decline until 2035 because the 
immature sharks that have been depleted in the past will age into the 
mature population over the next few decades, it is possible that the 
stock may be able to begin to rebuild if fishing mortality is low 
enough. Based on the above information, we find that future levels of 
total fishing mortality are not likely to lead to extirpation of the 
stock over the foreseeable future, even given estimates of historical 
and recent population decline. In the South Atlantic, the status of the 
shortfin mako shark is currently unclear. While it is probable that the 
population is experiencing declines due to high fishing effort, current 
stock status is highly uncertain, and it is difficult to predict the 
magnitude of decline over the next 50 years. The South Pacific has an 
increasing trend and there is no indication that this will change over 
the next 50 years, although this trend is based on a shorter time 
period, introducing some uncertainty into the future status of the 
species in this region. In the North Pacific, the ISC Shark Working 
Group stock assessment (2018) indicates that spawning abundances are 
expected to increase gradually over a 10-year period (2017-2026) if 
fishing mortality remains constant or is moderately decreased relative 
to 2013-2015 levels. We take this to indicate that the current levels 
of fishing mortality in this region are allowing the population to 
grow, and there is no indication that this will change significantly in 
the foreseeable future. In the Indian Ocean, it is difficult to 
determine the stock status over the foreseeable future as current stock 
status is highly uncertain, with declines potentially underestimated 
due to poor reporting and data problems discussed above. The best 
available scientific and commercial information for the species in this 
region, including two preliminary stock assessments, indicates that the 
species is undergoing overfishing but is not overfished, and recent 
increasing CPUE trends are indicated in Spanish, Portuguese, and 
Taiwanese longline fleets. Thus, although there is significant 
uncertainty regarding the future status of this stock, and we 
acknowledge that declines have been indicated, we conclude that the 
species is not at risk of extirpation in this region over the next 50 
years. In sum, although fishing mortality remains high throughout the 
species' range and its low productivity life history does present a 
concern for the species' risk of extinction over the foreseeable 
future, we conclude on the basis of the best available scientific and 
commercial data that the rangewide species is neither currently in 
danger of extinction nor likely to become so within the foreseeable 
future.

Significant Portion of Its Range

    Under the ESA and our implementing regulations, a species may 
warrant listing if it is in danger of extinction or likely to become so 
within the foreseeable future throughout all or a significant portion 
of its range. Having determined that the shortfin mako shark is not in 
danger of extinction or likely to become so within the foreseeable 
future throughout all of its range, we now consider whether the 
shortfin mako shark is in danger of extinction or likely to become so 
within the foreseeable future in a significant portion of its range--
that is, whether there is any portion of the species' range for which 
it is true that both (1) the portion is significant; and (2) the 
species, in that portion, is in danger of extinction or likely to 
become so within the foreseeable future. A joint USFWS-NMFS policy, 
finalized in 2014, provided the agencies' interpretation of this phrase 
(``SPR Policy,'' 79 FR 37578, July 1, 2014) and explains that, 
depending on the case, it might be more efficient for us to address the 
``significance'' question or the ``status'' question first. Regardless 
of which question we choose to address first, if we reach a negative 
answer with respect to the first question, we do not need to evaluate 
the other question for that portion of the species' range.
    We note that the definition of ``significant'' in the SPR Policy 
has been invalidated in two District Court cases that addressed listing 
decisions made by the USFWS. The SPR Policy set out a biologically-
based definition that examined the contributions of the members in the 
portion to the species as a whole, and established a specific threshold 
(i.e., when the loss of the members in the portion would cause the 
overall species to become threatened or endangered). The courts 
invalidated the threshold component of the definition because it set 
too high a standard. Specifically, the courts held that, under the 
threshold in the policy, a species would never be listed based on the 
status of the species in the portion, because in order for a portion to 
meet

[[Page 68265]]

the threshold, the species would be threatened or endangered rangewide. 
Center for Biological Diversity, et al. v. Jewell, 248 F. Supp. 3d 946, 
958 (D. Ariz. 2017); Desert Survivors v. DOI 321 F. Supp. 3d. 1011 
(N.D. Cal., 2018). However, those courts did not take issue with the 
fundamental approach of evaluating significance in terms of the 
biological significance of a particular portion of the range to the 
overall species. NMFS did not rely on the definition of ``significant'' 
in the policy when making this 12-month finding. The ERA Team instead 
chose to first address the question of the species' status in portions 
of its range. While certain other aspects of the policy have also been 
addressed by courts, the policy framework and key elements remain in 
place, and until the policy is withdrawn we are bound to apply those 
aspects of it that remain valid.
    Because there are infinite ways to divide up the species' range for 
an SPR analysis, the ERA Team only considered portions with a 
reasonable likelihood of being both in danger of extinction or likely 
to become so within the foreseeable future, and biologically 
significant to the species. In asking the ``status'' question first, 
the ERA Team considered whether the threats posed by overutilization 
and inadequate regulatory measures are geographically concentrated in 
any portion of the species' range at a biologically meaningful scale, 
or whether these threats are having a greater impact on the status of 
the species in any portions relative to other portions. While the 
shortfin mako shark is subject to the threat of overutilization in 
commercial fisheries across its range, fishing mortality is 
substantially affecting the species in the North Atlantic Ocean, and is 
projected to continue impacting the species' status in this region over 
the next several decades. Because the North Atlantic stock of shortfin 
mako shark is currently experiencing substantial negative effects of 
overfishing and inadequate regulatory mechanisms (i.e., declines in SSF 
of 50 percent from 1950 to 2015, as well as a 90 percent probability of 
being overfished and experiencing overfishing), and will continue to be 
impacted over the foreseeable future, the ERA Team concluded that there 
was a reasonable likelihood that the species is at greater risk of 
extinction in this portion relative to the remainder of the range and 
determined to proceed to consider whether in fact the individuals in 
that area were at moderate or high risk of extinction. The ERA Team 
also considered whether the Atlantic Ocean as a whole is a portion that 
may be at risk of extinction now or in the foreseeable future based on 
indications of the species' decline in this portion, and to ensure a 
thorough analysis of the species' status in this ocean basin.
    Separate from the ERA Team, we (NMFS) went on to consider whether 
other portions (the South Atlantic and the Indian Ocean) that were not 
explicitly considered by the ERA Team had a reasonable likelihood of 
being both in danger of extinction or likely to become so within the 
foreseeable future, and biologically significant to the species. In the 
South Atlantic, population declines of an unknown degree are likely 
occurring, and fishing mortality remains high. The best available 
scientific and commercial information indicates that the population has 
only a 19 percent probability of being overfished and experiencing 
overfishing, a 48 percent probability of not being overfished but 
overfishing occurring, or alternatively, being overfished but 
overfishing not occurring, and a 36 percent probability of not being 
overfished or experiencing overfishing (ICCAT 2017). The 2017 stock 
assessment of the population found conflicting results from different 
models, resulting in high uncertainty. However, the stock assessment 
notes that despite uncertainty, in recent years the stock may have been 
at, or is already below, BMSY, and fishing mortality is 
already exceeding FMSY. While the best available scientific 
and commercial information leads us to find that high levels of fishing 
mortality are likely leading to population declines in this region, 
there is no indication that the resulting decline reflects that the 
species in this portion has a reasonable likelihood of being in danger 
of extinction or likely to become so within the foreseeable future. 
Therefore, we did not consider the portion further. The best available 
scientific and commercial information indicates that the shortfin mako 
shark population in the Indian Ocean is considered to be experiencing 
overfishing but is not yet overfished, and recent CPUE increases have 
occurred in Spanish, Portuguese, and Taiwanese longline fleets. 
Although population declines are potentially underestimated due to poor 
reporting and data problems discussed previously, we do not have any 
indication that the preliminary stock assessments available for this 
region are invalid or suffer from methodological or other flaws that 
would lead us to discount them. As the stock is not considered 
overfished in either of these assessments, meaning that biomass has not 
declined below the biomass at which the stock can produce maximum 
sustainable yield on a continuing basis, we find it unlikely that 
fishing mortality is impacting abundance to a degree that causes the 
species to be at risk of extinction or likely to become so in the 
foreseeable future in this portion of its range. Therefore, the best 
available information does not support a conclusion that the species 
has a reasonable likelihood of being at greater risk of extinction in 
this portion relative to the remainder of the range, and the Indian 
Ocean was not assessed further in the SPR analysis. Overutilization of 
the species does not appear to be occurring in the Pacific Ocean: the 
North Pacific population appears stable and is neither overfished nor 
experiencing overfishing based on robust data, and the South Pacific 
population has been indicated to be increasing with moderate certainty. 
There is no indication that any region in the Pacific has a reasonable 
likelihood of being in danger of extinction or likely to become so 
within the foreseeable future, and therefore no portions in the Pacific 
Ocean were considered further. The ERA Team therefore went on to assess 
the extinction risk of two portions: the North Atlantic Ocean and the 
Atlantic Ocean as a whole.
    To determine extinction risk in each portion, the ERA Team used the 
likelihood point method as described previously in Methods. The ERA 
Team evaluated the best available information on the demographic 
threats and ESA Section 4(a)(1) factors for shortfin mako sharks in 
each portion, beginning with the North Atlantic Ocean portion. The 
recent stock assessment conducted by ICCAT indicates that the North 
Atlantic shortfin mako shark has experienced declines in biomass of 
between 47-60 percent from 1950-2015, and predicts that SSF will 
continue to decline until 2035 regardless of fishing mortality levels. 
Despite the species' low productivity and the relatively high level of 
fishing mortality impacting the species, the ERA Team concluded that 
the species is not at high risk of extinction based on the current 
abundance of the species in the portion (estimated at one million 
individuals by FAO (2019)) and recent increased efforts to reduce 
fishing mortality that are likely to be effective, at least to some 
degree, in reducing the effect of overutilization on the species here. 
Many of the ERA Team's points were placed in the moderate risk category 
for the North Atlantic Ocean portion, which is reflective of the 
species' low productivity and the considerable

[[Page 68266]]

uncertainty associated with potential effects of existing and future 
regulatory mechanisms aimed at rebuilding and ending overfishing of the 
North Atlantic shortfin mako stock over the next few decades (i.e., 
whether or not the resulting reduction in fishing mortality is 
significant enough to end overfishing and begin to rebuild the 
species). However, the ERA Team placed the majority of its likelihood 
points in the low risk category and concluded that the North Atlantic 
portion has a low extinction risk. Despite its continuing declining 
trend, based on the best available scientific and commercial 
information, the ERA Team did not conclude that the rate of decline in 
the foreseeable future would be great enough to put the species in this 
portion at high risk of extinction in the foreseeable future (see the 
Status Review Report).
    When conducting the analysis of the status of the species in the 
Atlantic Ocean as a whole, the ERA Team considered the highly uncertain 
fishing and abundance data available for the South Atlantic. Despite 
this uncertainty, the best available scientific and commercial data 
indicate that it is likely that the species' abundance in this region 
is declining, with ICCAT's SCRS finding a 19 percent probability that 
the stock is overfished and experiencing overfishing. The ERA Team also 
considered the possible effects of the retention prohibition in the 
North Atlantic and the potential for a shift in fishing effort for the 
species to the South Atlantic. Overall, the ERA Team found that the 
individuals of the species in the Atlantic Ocean portion as a whole 
were not at high risk of extinction based on available abundance and 
threats information. The ERA Team did place many points in the moderate 
risk category to reflect the species' low productivity, and the 
uncertainty in data and future regulatory mechanisms. However, the ERA 
Team placed the majority of its points in the low risk category because 
the level of fishing mortality and population decline expected within 
the foreseeable future does not place the species in this portion at 
high or moderate extinction risk in this timeframe.
    Thus, to summarize, the ERA Team did not find the shortfin mako 
shark to be in danger of extinction or likely to become so within the 
foreseeable future in either of these portions of its range. As a 
result, the ERA Team did not continue the analysis to evaluate whether 
either of these portions constitutes a biologically significant portion 
of the shortfin mako shark's range.
    We agree with the ERA Team's conclusions that the species is not in 
danger of extinction now within the North Atlantic or the Atlantic 
Ocean as a whole. When we extended the foreseeable future to 50 years, 
which we have determined is more appropriate to apply for this species, 
we also reached the same conclusion as the ERA Team. The North Atlantic 
shortfin mako shark population is estimated to have experienced 
declines in total biomass of 47-60 percent and declines in SSF of 50 
percent from 1950 to 2015 (ICCAT 2017). Since then, levels of fishing 
mortality in the North Atlantic have declined in response to management 
measures implemented in recent years (3,281 t in 2015; 3,356 t in 2016; 
3,199 t in 2017; 2,373 t in 2018; 1,882 t in 2019; 1,709 t in 2020) 
(SCRS 2021). While we recognize that current levels of mortality (1,709 
t in 2020) are higher than any of the TAC levels examined in the 
projections carried out by the SCRS (up to 1,100 t inclusive of dead 
discards, ICCAT 2019), over the next 50 years, recently adopted 
retention prohibitions and increasing international efforts to reduce 
the effects of fishing mortality on the species in this region will 
likely result in further decreasing levels of fishing mortality in this 
region (although we are unable to conclude the magnitude of potential 
declines, or whether they will be large enough to rebuild the stock). 
Therefore, the best available scientific and commercial information 
supports our forecast that the rate of decline will likely slow 
compared to the 1950-2015 time period. Although the stock is expected 
to decline until 2035 because the immature sharks that have been 
depleted in the past will age into the mature population over the next 
few decades, it is possible that the stock may be able to begin to 
rebuild if fishing mortality is low enough. We find that future levels 
of fishing mortality are not likely to place the species in danger of 
extinction in the foreseeable future within this portion, even given 
estimates of historical and recent decline. In the South Atlantic, it 
is likely that the population is experiencing decline of an unknown 
degree due to continued high fishing effort and mortality. Results of 
the 2017 stock assessment indicate a 19 percent probability that the 
stock is overfished and experiencing overfishing, with conflicting 
results from different models used. Current stock status is highly 
uncertain, and it is therefore difficult to predict the magnitude of 
decline over the next 50 years. However, the greater abundance, habitat 
area, spatial distribution, and ecological diversity of the North and 
South Atlantic populations together as a portion provide additional 
resilience that makes extinction less likely. Therefore, we do not find 
that the Atlantic portion is likely to be in danger of extinction in 
the foreseeable future. Because we did not find the shortfin mako shark 
to be in danger of extinction or likely to become so within the 
foreseeable future in either of these portions, and because to support 
a listing on the basis of SPR the individuals in a portion would need 
to both have a threatened or endangered status and be biologically 
significant to the overall species, we did not consider whether these 
portions qualify as significant portions of the shortfin mako shark's 
range.

Distinct Population Segments

    The petition to list the shortfin mako shark requested that NMFS 
list the species throughout its range, or alternatively, as DPSs, in 
the event that NMFS concludes that they exist. Therefore, we examined 
the best available information to determine whether DPSs may exist for 
this species. The petition did not provide information regarding 
potential DPSs of shortfin mako shark.
    As discussed previously, the DPS Policy provides guidelines for 
defining DPSs and identifies two elements to consider in a decision 
regarding whether a population qualifies as a DPS: discreteness and 
significance of the population segment to the species (61 FR 4722; 
February 7, 1996). A population may be considered discrete if it is 
markedly separate from other populations of the same taxon as a 
consequence of physical, physiological, ecological, or behavioral 
factors, or if it is delimited by international governmental 
boundaries. Genetic differences between the population segments being 
considered may be used to evaluate discreteness. If a population 
segment is considered discrete, its biological and ecological 
significance must then be evaluated. Significance is evaluated in terms 
of the importance of the population segment to the overall welfare of 
the species. Some of the considerations that can be used to determine a 
discrete population segment's significance to the taxon as a whole 
include: (1) persistence of the population segment in an unusual or 
unique ecological setting; (2) evidence that loss of the population 
segment would result in a significant gap in the range of the taxon; 
and (3) evidence that the population segment differs markedly from 
other populations of the species in its genetic characteristics.

[[Page 68267]]

    To determine whether any discrete populations of shortfin mako 
sharks exist, we looked at available information on shortfin mako shark 
population structure, including tagging, tracking, and genetic studies. 
As discussed previously in Habitat Use and Population Structure and 
Genetics, although certain ocean currents and features may limit 
movement patterns between different regions, available genetic studies 
indicate a globally panmictic population with some genetic structuring 
among ocean basins.
    Heist et al. (1996) investigated genetic population structure using 
restriction fragment length polymorphism analysis of maternally 
inherited mtDNA from shortfin mako sharks in the North Atlantic, South 
Atlantic, North Pacific, and South Pacific. The North Atlantic samples 
showed significant isolation from other regions (p <0.001), and 
differed from other regions by the relative lack of rare and unique 
haplotypes, and high abundance of a single haplotype (Heist et al. 
1996). Reanalysis of the data found significant differentiation between 
the South Atlantic and North Pacific samples (Schrey and Heist 2003) in 
addition to isolation of the North Atlantic.
    A microsatellite analysis of samples from the North Atlantic, South 
Atlantic (Brazil), North Pacific, South Pacific, and Atlantic and 
Indian coasts of South Africa found very weak evidence of population 
structure (FST = 0.0014, P = 0.1292; RST = 
0.0029, P = 0.019) (Schrey and Heist 2003). These results were 
insufficient to reject the null hypothesis of a single genetic stock of 
shortfin mako shark, suggesting that there is sufficient movement of 
shortfin mako sharks, and therefore gene flow, to reduce genetic 
differentiation between regions (Schrey and Heist 2003). The authors 
note that their findings conflict with the significant genetic 
structure revealed through mtDNA analysis by Heist et al. (1996). They 
suggest that as mtDNA is maternally inherited and nuclear DNA is 
inherited from both parents, population structure shown by mtDNA data 
could indicate that female shortfin mako sharks exhibit limited 
dispersal and philopatry to parturition sites, while male dispersal 
allows for gene flow that would explain the results from the 
microsatellite data (Schrey and Heist 2003).
    Taguchi et al. (2011) analyzed mtDNA samples from the North and 
South Pacific, North Atlantic, and Indian Oceans, finding evidence of 
significant differentiation between the North Atlantic and the Central 
North Pacific and Eastern South Pacific (pairwise [Phi]ST = 
0.2526 and 0.3237, respectively). Interestingly, significant structure 
was found between the eastern Indian Ocean and the Pacific Ocean 
samples (pairwise [Phi]ST values for Central North Pacific, 
Western South Pacific, Eastern South Pacific are 0.2748, 0.1401, and 
0.3721, respectively), but not between the eastern Indian and the North 
Atlantic.
    Corrigan et al. (2018) also found evidence of matrilineal structure 
from mtDNA data, while nuclear DNA data provide support for a globally 
panmictic population. Although there was no evidence of haplotype 
partitioning by region and most haplotypes were found across many 
(sometimes disparate) locations, Northern Hemisphere sampling locations 
were significantly differentiated from all other samples, suggesting 
reduced matrilineal gene flow across the equator (Corrigan et al. 
2018). The only significant differentiation indicated by microsatellite 
data was between South Africa and southern Australia (pairwise 
FST = 0.037, [Phi]ST = 0.043) (Corrigan et al. 
2018). Clustering analysis showed only minor differences in allele 
frequencies across regions, and little evidence of population structure 
(Corrigan et al. 2018). Overall, the authors conclude that although 
spatial partitioning exists, the shortfin mako shark is genetically 
homogenous at a large geographic scale.
    Taken together, results of genetic analyses suggest that female 
shortfin mako sharks exhibit fidelity to ocean basins, possibly to 
utilize familiar pupping and rearing grounds, while males move across 
the world's oceans and mate with females from various basins (Heist et 
al. 1996; Schrey and Heist 2003; Taguchi et al. 2011; Corrigan et al. 
2018). This finding does not support the existence of discrete 
population segments of shortfin mako sharks.
    We also considered whether available tracking data support the 
existence of discrete population segments of shortfin mako shark. There 
is some evidence that certain ocean currents and features may limit 
movement patterns, including the Mid-Atlantic ridge separating the 
western and eastern North Atlantic, and the Gulf Stream separating the 
North Atlantic and the Gulf of Mexico/Caribbean Sea (Casey and Kohler 
1992; Vaudo et al. 2017; Santos et al. 2020). However, conventional 
tagging data indicates that movement does occur across these features 
(Kohler and Turner 2019). In the Pacific, tagging data supports east-
west mixing in the north and minimal east-west mixing in the south 
(Sippel et al. 2016; Corrigan et al. 2018). Trans-equatorial movement 
may be uncommon based on some tagging studies, though tagged shortfin 
mako sharks have been recorded crossing the equator (Sippel et al. 
2016; Corrigan et al. 2018; Santos et al. 2021). Therefore, we conclude 
that there do not appear to be major barriers to the species' dispersal 
that would result in marked separation between populations.
    Overall, we find that the best available scientific and commercial 
information does not support the existence of discrete populations of 
shortfin mako shark. Because both standards, of discreteness and 
significance, have to be met in order to conclude that a population 
would constitute a DPS, we conclude that there are no population 
segments of the shortfin mako shark that would qualify as a DPS under 
the DPS Policy.

Final Listing 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 relied on available literature and information 
from relevant countries to evaluate efforts to protect and conserve the 
species, including National Plans of Action for the Conservation and 
Management of Sharks (NPOA-Sharks), which are developed under the IPOA-
SHARKS and aim to ensure the conservation, management, and long-term 
sustainable use of sharks. While the development of NPOAs provide some 
indication of the level of commitment of a catching country to manage 
its shark fisheries and provides a benefit to sharks, the quality of 
existing NPOA-Sharks varies, and there are no reporting mechanisms on 
implementation of the NPOAs; thus, it remains uncertain whether a 
particular plan is being implemented or what impact the plan has had on 
conservation and management of sharks. These conservation efforts do 
not change the conclusion we would otherwise have reached regarding the 
species' status. We have independently reviewed the best available 
scientific and commercial information, including the petitions, public 
comments submitted in response to the 90-day finding (86 FR 19863; 
April 15, 2021), the Status Review Report, and other published and 
unpublished information. We considered each of the statutory factors to 
determine whether each contributed significantly to the extinction risk 
of the species. As required by the ESA, section 4(b)(1)(a), we also 
took into account

[[Page 68268]]

efforts to protect shortfin mako sharks by states, foreign nations, or 
political subdivisions thereof, and evaluated whether those efforts 
provide a conservation benefit to the species. As previously explained, 
we could not identify a significant portion of the species' range that 
is threatened or endangered, nor did we find that any DPSs of the 
species exist. Therefore, our determination is based on a synthesis and 
integration of the foregoing information, factors and considerations, 
and their effects on the status of the species throughout its entire 
range.
    We have determined the shortfin mako shark is not presently in 
danger of extinction, nor is it likely to become so in the foreseeable 
future throughout all or a significant portion of its range. This 
finding is consistent with the statute's requirement to base our 
findings on the best scientific and commercial data available, 
summarized and analyzed above. Therefore, the shortfin mako shark does 
not meet the definition of a threatened species or an endangered 
species and does not warrant listing as threatened or endangered at 
this time.
    This is a final action, and, therefore, we are not soliciting 
public comments.

References

    A complete list of the references used in this 12-month finding is 
available online (see ADDRESSES) and upon request (see FOR FURTHER 
INFORMATION CONTACT).

Peer Review

    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. Three independent specialists were selected from 
the academic and scientific community for this review. All peer 
reviewer comments were addressed prior to dissemination of the final 
Status Review Report and publication of this 12-month finding. The Peer 
Review Report can be found online at: https://www.noaa.gov/information-technology/endangered-species-act-status-review-report-shortfin-mako-shark-isurus-oxyrinchus-id430.
    Authority: The authority for this action is the Endangered Species 
Act of 1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: November 4, 2022.
Samuel D. Rauch, III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.
[FR Doc. 2022-24493 Filed 11-10-22; 8:45 am]
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