Endangered and Threatened Wildlife and Plants; Notice of 12-Month Finding on a Petition To List the Dwarf Seahorse as Threatened or Endangered Under the Endangered Species Act, 45377-45389 [2020-16335]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 85, Number 145 (Tuesday, July 28, 2020)]
[Notices]
[Pages 45377-45389]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-16335]


-----------------------------------------------------------------------

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[Docket No. 200716-0193; RTID 0648-XA496]


Endangered and Threatened Wildlife and Plants; Notice of 12-Month 
Finding on a Petition To List the Dwarf Seahorse 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.

-----------------------------------------------------------------------

SUMMARY: We, NMFS, announce a 12-month finding and listing 
determination on a petition to list the dwarf seahorse (Hippocampus 
zosterae) as threatened or endangered under the Endangered Species Act 
(ESA). We have completed a status review of the dwarf seahorse in 
response to a petition submitted by the Center for Biological 
Diversity. After reviewing the best scientific and commercial data 
available, including the Status Review Report, we have determined the 
species does not warrant listing at this time. While the species has 
declined in abundance, it still occupies its historical range, and 
population trends indicate subpopulations are stable or increasing in 
most locations. We conclude that the dwarf seahorse is not currently in 
danger of extinction throughout all or a significant portion of its 
range and is not likely to become so within the foreseeable future.

DATES: This finding was made on July 28, 2020.

ADDRESSES: The dwarf seahorse Status Review Report associated with this 
determination and its references are available upon request from the 
Species Conservation Branch Chief, Protected Resources Division, NMFS 
Southeast Regional Office, 263 13th Avenue South, St. Petersburg, FL 
33701, Attn: Dwarf Seahorse 12-month Finding. The report and references 
are also available electronically at: https://www.cio.noaa.gov/services_programs/prplans/ID411.html.

FOR FURTHER INFORMATION CONTACT: Adam Brame, NMFS Southeast Regional 
Office, (727) 209-5958; or Celeste Stout, NMFS Office of Protected 
Resources, 301-427-8436.

SUPPLEMENTARY INFORMATION: 

Background

    On April 6, 2011, we received a petition from the Center for 
Biological Diversity to list the dwarf seahorse as threatened or 
endangered under the ESA. The petition asserted that (1) the present or 
threatened destruction, modification, or curtailment of habitat or 
range; (2) overutilization for commercial, recreational, scientific, or 
educational purposes; (3) inadequacy of existing regulatory mechanisms; 
and (4) other natural or manmade factors are affecting its continued 
existence and contributing to the dwarf seahorse's imperiled status. 
The petitioner also requested that critical habitat be designated for 
this species concurrent with listing under the ESA.
    On May 4, 2012, NMFS published a 90-day finding for dwarf seahorse 
with our determination that the petition presented substantial 
scientific and commercial information indicating that the petitioned 
action may be warranted (77 FR 26478). We also requested scientific and 
commercial information from the public to inform a status review of the 
species, as required by

[[Page 45378]]

section 4(b)(3)(a) of the ESA. Specifically, we requested information 
pertaining to: (1) Historical and current distribution and abundance of 
this species throughout its range; (2) historical and current 
population status and trends; (3) life history in marine environments; 
(4) curio, traditional medicine, and aquarium trade or other trade 
data; (5) any current or planned activities that may adversely impact 
the species; (6) historical and current seagrass trends and status; (7) 
ongoing or planned efforts to protect and restore the species and its 
seagrass habitats; (8) management, regulatory, and enforcement 
information; and (9) any biological information on the species. We 
received information from the public in response to the 90-day finding 
and incorporated the information into both the Status Review Report 
(NMFS 2020) and this 12-month finding.

Listing Determinations Under the ESA

    We are responsible for determining whether the dwarf seahorse is 
threatened or endangered under the ESA (16 U.S.C. 1531 et seq.). 
Section 4(b)(1)(A) of the ESA requires us to make listing 
determinations based solely on the best scientific and commercial data 
available after conducting a review of the status of the species and 
after taking into account efforts being made by any state or foreign 
nation to protect the species. 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 taxonomic species and ``any 
subspecies of fish, or wildlife, or plants, and any distinct population 
segment of any species of vertebrate fish or wildlife which interbreeds 
when mature.'' On February 7, 1996, NMFS and the U.S. Fish and Wildlife 
Service (USFWS; together, the Services) adopted a policy describing 
what constitutes a distinct population segment (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.'' Thus, we 
interpret an ``endangered species'' to be one that is presently in 
danger of extinction. A ``threatened species,'' on the other hand, is 
not currently in danger of extinction but is likely to become so in the 
foreseeable future. In other words, a key statutory difference between 
a threatened and endangered species is the timing of when a species may 
be 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 due to any of the following five 
factors: (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence.
    To determine whether the dwarf seahorse warrants listing under the 
ESA, we formed a Status Review Team (SRT) consisting of biologists and 
managers to complete a Status Review Report (NMFS 2020), which 
summarizes the taxonomy, distribution, abundance, life history and 
biology of the species. The Status Review Report (NMFS 2020) also 
identifies threats or stressors affecting the status of the species, 
and provides a description of fisheries, fisheries management, and 
conservation efforts. The team then assessed the threats affecting 
dwarf seahorse as part of an extinction risk analysis (ERA). The 
results of the ERA from the Status Review Report (NMFS 2020) are 
discussed below. The Status Review Report incorporates information 
received in response to our request for information (77 FR 26478, May 
4, 2012) and comments from three independent peer reviewers. 
Information from the Status Review Report is summarized below in the 
Biological Review section.
    The petition requested that the species be considered for 
endangered or threatened status as a single entity throughout its 
range. While the agency has discretion to evaluate a species for 
potential DPSs, it is our policy, in light of Congressional guidance 
(S. Rep. 96-151), to list DPSs sparingly. The SRT held discussions as 
to whether DPSs should be considered, based on the information within 
the Status Review Report (NMFS 2020), but ultimately decided to 
evaluate the dwarf seahorse as a singular species throughout its range.
    In determining whether the species is endangered or threatened as 
defined by the ESA, we considered both the data and information 
summarized in the Status Review Report (NMFS 2020) as well as the 
results of the ERA. The ERA analyzed demographic and listing factors 
that could affect the status of the dwarf seahorse. Demographic factors 
considered included abundance, population growth rate and productivity, 
spatial structure/connectivity, and diversity. We also identified 
threats under each of the five listing factors: (A) Present or 
threatened destruction, modification, or curtailment of its habitat or 
range; (B) overutilization of the species for commercial, recreational, 
scientific, or educational purposes; (C) disease or predation; (D) 
inadequacy of existing regulatory mechanisms; and (E) other natural or 
manmade factors affecting its continued existence. For purposes of our 
analysis, the identification of demographic or listing factors that 
could impact a species negatively is not sufficient to compel a finding 
that ESA listing is warranted. In considering those factors that might 
constitute threats, we look beyond mere exposure of the species to the 
factors to determine whether the species responds, either to a single 
threat or multiple threats, in a way that causes impacts at the species 
level. We considered each threat identified, both individually and 
cumulatively, evaluating both their nature and the species' response to 
the threat. In making this 12-month finding, we have considered and 
evaluated the best available scientific and commercial information, 
including information received in response to our 90-day finding.

Biological Review

    This section provides a summary of key biological information 
presented in the Status Review Report (NMFS 2020).

Species Description

    The dwarf seahorse (Hippocampus zosterae, Jordan and Gilbert 1882), 
is a short-lived, small-sized syngnathid fish. Like all seahorses, the 
tail of the dwarf seahorse is prehensile (capable of grasping) and used 
to secure the animal to seagrass or floating marine vegetation in the 
water (Gill 1905; Walls 1975). The eyes move independently of one 
another, allowing for better accuracy during feeding (Gill 1905). Dwarf 
seahorses have a wide range of color patterns from yellow and green to 
black. Individuals may also have white markings or dark spots which aid 
in camouflage while inhabiting seagrass (Gill 1905; Lourie et al. 2004; 
Lourie et al. 1999; Vari 1982).
    Dwarf seahorses are one of the smallest species of seahorses.

[[Page 45379]]

Aquarium-raised dwarf seahorses have been recorded at 0.27-0.35 inches 
(0.7-0.9 cm) total length (TL) at birth and growing to 0.7 inches (1.8 
cm) TL by day 17 (Koldewey 2005). There is some discussion regarding 
the maximum size of adults with reports ranging from 1 inch (2.5 cm; 
Lourie et al. 2004) to a single specimen at 2.12 inches (5.4 cm; 
Masonjones, University of Tampa, pers. comm. to Kelcee Smith, 
Riverside, Inc., on July 17, 2013). Masonjones et al. (2010) indicated 
body size was highly correlated with season, as individuals born in the 
Florida wet season (June-September) were larger than those born in the 
dry season. The species rarely lives longer than 2 years in the wild 
(Koldewey 2005; Strawn 1958; Vari 1982), though it has been reported to 
live up to 3 years in captivity (Abbott 2003).

Distribution

    Historically, dwarf seahorses have been reported in the 
southeastern United States, including Texas, Louisiana, Mississippi, 
Alabama, and Florida (Strawn 1958), Mexico, and the greater Caribbean, 
including The Bahamas, Bermuda, and Cuba. Data from outside the United 
States are limited, and reports from the Bahamas, Cuba, and Bermuda 
have been rare historically and absent recently. Available data from 
the United States, both historically and presently, indicate the 
highest abundances of dwarf seahorses are in bay systems south of 
29[deg] N (south Florida and south Texas) and the lowest abundances are 
in Alabama, Louisiana, and Mississippi (NMFS 2020).

Habitat

    In general, dwarf seahorse habitat is characterized by shallow, 
warm, nearshore seagrass beds. These habitats often occur within 
sheltered lagoons or embayments with reduced exposure to strong 
currents and heavy wave action (Iverson and Bittaker 1986). Dwarf 
seahorses are typically found in shallow coastal and lagoon habitats 
during the summer (Musick et al. 2000; Robbins 2005; Strawn 1961; 
Tipton and Bell 1988; Walls 1975) and deeper waters or tide pools 
during the winter (Lourie et al. 2004). Dwarf seahorses show no 
particular affinity for a specific seagrass species (Masonjones et al. 
2010), but are generally found in areas with higher densities of 
seagrass blades and higher seagrass canopy (i.e., length of seagrass 
blades) (Lourie et al. 2004). This results in a patchy distribution of 
dwarf seahorses within estuaries.
    Dwarf seahorses are found within a range of salinities (7-37), 
temperatures (57-89[deg] F (14-32[deg] C)), and depths, depending on 
geographic location and time of year (Ryan Moody, Dauphin Island Sea 
Lab, pers. comm. to Kelcee Smith, Riverside, Inc., on July 17, 2012; 
Masonjones and Rose 2009; Masonjones et al. 2010; Mark Fisher, Texas 
Parks & Wildlife Dept., pers. comm. to Kelcee Smith, Riverside, Inc., 
on July 12, 2012; Mike Harden, Louisiana Dept. of Natural Resources, 
pers. comm. to Kelcee Smith, Riverside, Inc., July 24, 2012). However, 
within aquarium husbandry the dwarf seahorse is considered a tropical 
species, and water temperatures of 68-79[deg] F are recommended (20-
26[deg] C; Masonjones 2001; Koldewey 2005). In their review paper, 
Foster and Vincent (2004) reported the maximum recorded depth for the 
dwarf seahorse as 6.5 feet (2 meters).

Diet and Feeding

    Seahorses are ambush predators, feeding on harpacticoid copepods 
and amphipods (both very small crustaceans measuring only a few 
millimeters in length) as they drift along the edges of seagrass beds 
(Huh and Kitting 1985; Tipton and Bell 1988). No seasonal differences 
have been reported in the dwarf seahorse diet (Tipton and Bell 1988). 
Dwarf seahorses produce a stridulatory sound (a ``click'') from the 
articulation of the supraoccipital and coronet bones in the skull 
during feeding, and it has been shown that dwarf seahorses click 93 
percent of the time during feeding in a new environment, and during 
competition for mates (Colson et al. 1998).

Reproductive Biology

    Dwarf seahorses reach reproductive maturity at approximately 3 
months of age (Wilson and Vincent 2000) and exhibit gender-specific 
roles in reproduction (Masonjones and Lewis 1996; Masonjones and Lewis 
2000; Vincent 1994). Dwarf seahorses are generally monogamous (the 
practice of an individual having one mate) within a breeding season and 
mates are chosen by similarity in size (Jones et al. 2003; Wilson et 
al. 2003). Dwarf seahorses will reject a potential mate if the size 
difference is too large (Masonjones et al. 2010). Once bonded, the 
mating pair remains together throughout a 3-day courtship ritual. After 
successful courtship, the female deposits unfertilized eggs into the 
male's brood pouch. In the brood pouch, eggs are fertilized and the 
embryos are nourished, osmoregulated (the body fluid balance and 
concentration of salts is kept stable), oxygenated (by circulating 
water), and protected (Jones et al. 2003; Vincent 1995a; Wilson et al. 
2003; Wilson and Vincent 2000). Strawn (1958) reported a maximum number 
of 69 eggs found in the ovaries of a female and up to 55 young counted 
in the pouch of a male. Masonjones and Lewis (1996) found that males 
give birth to an average of 3-16 offspring per brood. Males in 
captivity usually give birth to fewer individuals compared to males in 
the wild (Masonjones et al. 2010). Throughout the 10-12-day gestation 
(Masonjones and Lewis 2000) the female greets the male daily and the 
pair remains in close proximity (Jones et al. 2003; Vincent 1995a; 
Wilson and Vincent 2000).
    Dwarf seahorses exhibit iteroparity (multiple reproductive cycles) 
throughout the breeding season (Masonjones and Lewis 1996; Masonjones 
and Lewis 2000; Rose et al. 2014). Following the transfer of eggs, the 
female begins developing new eggs for the next clutch (Masonjones and 
Lewis 1996; Masonjones and Lewis 2000). Egg development is achieved in 
2 days but the female is only sexually receptive for a few hours 
following development and is ``essentially incapable of mating before 
the end of their previous mating partner's gestation period'' 
(Masonjones and Lewis 2000). Under ideal conditions, the male can mate 
4-20 hours after giving birth, allowing dwarf seahorse pairs to produce 
up to two broods per month (Masonjones and Lewis 2000; Strawn 1958; 
Vari 1982). Masonjones and Lewis (2000) reported the potential number 
of offspring that male and female dwarf seahorses could produce over 
the breeding season were 279.5 and 240.5 individuals, respectively. 
This difference in potential offspring between the two sexes is a 
result of latency, as males are faster to respond to new potential 
mates if the pair bond is disrupted (if one dies or is removed). If the 
female dies or is removed during gestation, the male will give birth to 
that clutch before finding a new mate. If a pregnant male (a male 
carrying fertilized eggs) dies or is removed, the female will not mate 
until the gestation for the interrupted pregnancy would have been 
complete (Masonjones and Lewis 2000).
    Dwarf seahorse breeding season is generally protracted and is 
influenced by day length and water temperature (Koldewey 2005; 
Masonjones and Lewis 2000; Strawn 1958; Vari 1982). Breeding occurs 
year-round at latitudes south of approximately 28[deg] N (Rose et al. 
2019). During the summer months, when the day length is longer and 
water temperature exceeds 86[deg] F (30[deg] C), dwarf seahorses 
reproduce more frequently because gestation is shorter (Fedrizzi et al. 
2015; Foster and Vincent 2004). For

[[Page 45380]]

example, in Tampa Bay, Florida, pregnant males are found in all months 
but are more abundant early summer through fall (Rose et al. 2019). 
Year round reproduction was also observed in the Florida Keys, based on 
anecdotal reports from commercial collectors (FWC 2016).

Population Structure and Genetics

    Fedrizzi et al. (2015) investigated dwarf seahorse population 
genetic structure at eight Florida locations: One in the Panhandle 
(Pensacola), two adjacent to Tampa Bay, four in the Florida Keys, and 
one in Indian River Lagoon. The study found significant population 
structuring with a strongly separated population in the Panhandle, two 
recognizable subpopulations in the Florida Keys, and a potential fourth 
subpopulation at Big Pine Key. Dwarf seahorses from the Indian River 
Lagoon were not delineated as a discrete population, due to small 
sample size and lack of consistency in relationship to the other 
populations. Despite overall population structuring, Fedrizzi et al. 
(2015) observed evidence of some gene flow between sampled locations, 
with the exception of the Florida Panhandle. The results suggest that 
the subpopulations of Florida's dwarf seahorses that are closest to 
each other are more genetically similar than those that are further 
apart. Interestingly, the distance between the sites sampled by 
Fedrizzi et al. (2015) is greater than the distance over which 
Florida's dwarf seahorses have been shown to actively migrate 
(Masonjones et al. 2010). Thus, genetic connectivity between 
subpopulations is more likely the result of individuals dispersing to 
neighboring subpopulations through rafting.

Status Assessments

    There have been no formal status assessments conducted for the 
dwarf seahorse throughout its range. While the species has been 
documented from Florida to Texas in the United States and Cuba, The 
Bahamas, Bermuda and Mexico internationally, data are generally lacking 
outside of Florida. Given the paucity of data outside the United 
States, we are unsure of the status of dwarf seahorse in these other 
countries. Studies indicate dwarf seahorse subpopulations have steadily 
decreased throughout their range since the 1970s due to loss of habitat 
and are noted as rare in parts of its former range (Koldewey 2005; 
Musick et al. 2000). Our evaluation of available data reviewed during 
the status review supports this assertion, as the species is rarely 
collected along the north coast of the Gulf of Mexico and relative 
abundance has declined since the 1990s in long-term fishery-independent 
data from Florida (Figure 3 in NMFS 2020). It is unlikely that the 
dwarf seahorse ever fully occupied the northern Gulf of Mexico due to 
winter water temperatures below the species' optimal limits and the 
general lack of available seagrass habitat, as compared to Florida and 
south Texas (Handley et al. 2007). Current data indicate that the 
species remains common along the south and southwest coasts of Florida, 
specifically west Florida from Tampa Bay to the Florida Keys.
    In Florida, the species appears to be most abundant in five 
estuaries: Charlotte Harbor, Tampa Bay, Sarasota Bay, Biscayne Bay, and 
Florida Bay, which the SRT considers to be the core area of abundance 
critical to the population, based on available seagrass habitat and the 
species' thermal tolerance. Long-term dwarf seahorse abundance in 
Charlotte Harbor and Tampa Bay estuaries has declined, but population 
abundance has remained stable at a lower level since 2009 when the 
commercial harvest trip limit regulations (see 68B-42, F.A.C.) went 
into effect (FWC unpublished data). Rose et al. (2019) found Tampa Bay 
dwarf seahorse was a robust subpopulation with stable densities across 
3 years and year[hyphen]round breeding. Additionally, Tampa Bay dwarf 
seahorse densities in 2008-2009 (Rose et al. 2019) were significantly 
higher than those reported for 2005-2007 (Masonjones et al. 2010). The 
U.S. Geological Survey data from Florida Bay and Biscayne Bay suggest 
the relative abundance of dwarf seahorse was stable within these 
systems over the short duration (2005-2009) of their study. 
Cumulatively, the best available information on the dwarf seahorse's 
status suggests that Florida Bay has the highest relative abundance of 
dwarf seahorse.
    Carlson et al. (2019) estimated dwarf seahorse population size in 
five regions of Florida using a population viability model. Initial 
population size estimates were developed for the following 
subpopulations; Cedar Key, Tampa Bay, Charlotte Harbor, Florida Bay, 
and North Indian River Lagoon, based on all known existing survey data. 
Known density estimates varied from 0.0-0.59 N/m\2\ (individuals per 
square meter) with highest densities in the most southern Bays (i.e., 
Florida Bay and Biscayne Bay) and lower estimates in Tampa Bay, 
southwest Florida, and north Florida (Table 2 in Carlson et al. 2019). 
Carlson et al. (2019) derived initial estimates of subpopulation size 
by using all available dwarf seahorse density observations to create 
10,000 bootstrapped samples (simulated outcomes). The 5 percent or 10 
percent quantiles of seahorse density estimates (0.0009 N/m\2\ and 
0.003 N/m\2\, respectively) from the bootstrapped samples were then 
multiplied by the available seagrass acreage in nearshore waters 
(Yarbro and Carlson 2016). Carlson et al. (2019) used the 5 percent or 
10 percent quantiles to conservatively account for variability in dwarf 
seahorse distribution within seagrass meadows (greater density of dwarf 
seahorse in areas with higher density of seagrass blades and higher 
seagrass canopy (Lourie et al. 2004)). As dwarf seahorses are most 
abundant in bay systems south of 29[deg] N latitude, Carlson et al. 
(2019) applied the density estimate from the 10 percent quantile (0.003 
N/m\2\) for the Tampa Bay, Charlotte Harbor and Florida Bay 
subpopulations (those south of 29[deg] N latitude) and the 5 percent 
quantile (0.0009 N/m\2\) for the Cedar Key and north Indian River 
Lagoon subpopulations (north of 29[deg] N latitude). Retrospective 
projections from these conservative initial estimates suggested male 
subpopulation sizes in 2016 ranged from about 15,258 at Cedar Key to 
9,910,752 in Florida Bay. Assuming a female biased sex ratio of 58.2/
41.8 (Rose et al. 2019), the total estimated population across the five 
modeled subpopulations exceeded 29 million individual dwarf seahorse in 
2016.
    The population abundance estimates from Carlson et al. (2019) are 
likely conservative for the following reasons: (1) The starting 
densities derived from the 5 percent or 10 percent quantiles of the 
bootstrapped samples are expected to be underestimates of the actual 
densities for each subpopulation; (2) the intrinsic rate of population 
increase (Rmax) was conservatively estimated (assumed equal 
to the dominant eigenvalue (an indicator of variance in the data) of 
the Leslie matrix (an age-structured model of population growth) at 
starting conditions prior to density-dependence (Cortes 2016)) and was 
much lower than estimated Rmax for other seahorse species 
(Denney et al. 2002, Curtis 2004); (3) the RAMAS model used by Carlson 
et al. (2019) accounted for variability in survivorship of each age 
class resulting in 98 percent of reproduction generated by the Age-0 
class (suggests nearly all reproduction is carried out in the first 
year so any reproduction after the first year is generally unaccounted 
for even though it could be occurring); (4) carrying capacity in 
seagrass habitats was capped at the 25 percent quantile estimate from 
the bootstrapped data (0.02 N/m\2\),

[[Page 45381]]

which is likely an underestimate; (5) a 30 percent mortality rate was 
assumed for acute cold exposure although greater thermal tolerance is 
suggested by Mascar[oacute] et al. (2016); and (6) a theoretical 
mortality rate of 100 percent for harmful algal bloom (HAB) exposure 
was assumed, with HABs assumed to cover 25 percent to 50 percent of 
available seagrass habitat within a given estuary, despite limited 
observations of HAB overlap with seagrass beds in coastal bays (NOAA-
HABSOS 2018).

Extinction Risk Analysis

    The SRT relied on the best information available to conduct an ERA 
through evaluation of four demographic viability factors and five 
threats-based listing factors. The SRT, which consisted of three NOAA 
Fisheries Science Center and Regional Office personnel, was asked to 
independently evaluate the severity, scope, and certainty for these 
threats currently and in the foreseeable future. The SRT defined the 
foreseeable future as the timeframe over which threats that impact the 
biological status of the species can be reliably predicted.
    Several foreseeable future scenarios were considered. The different 
foreseeable futures were based on the ability to forecast different 
primary threats and the species response to these threats through time. 
As outlined in the Status Review Report (NMFS 2020), habitat loss 
associated with climate change, overutilization in a targeted fishery, 
and stochastic events such as HABs and cold weather events are the 
greatest threats to the species. These threats affect dwarf seahorse 
populations over different time scales. Stochastic events such as HABs 
and severe cold events are generally restricted in geographic space, 
duration, and frequency and therefore are likely short-term threats. 
Directed harvest is a longer-term threat; however, harvest regulations 
can be dynamically adapted to promote sustainability. Contemporary 
models forecast climate change effects several decades into the future; 
thus, climate change is considered a long-term threat.
    The response of dwarf seahorses was considered over the timeframes 
associated with the major threats. Dwarf seahorse subpopulations have 
demonstrated remarkable resilience to stochastic events, with apparent 
large population declines followed by large population increases (NMFS 
2020). The response of dwarf seahorses to long-term threats was 
difficult to predict given the species' life history, including 
longevity and generation time. At approximately 1-3 years (Abbott 2003; 
Koldewey 2005; Strawn 1958; Vari 1982), dwarf seahorse longevity is 
very short in comparison to many other teleost fish. Dwarf seahorses 
reach sexual maturity in about 3 months (Strawn 1953; Strawn 1958; 
Koldewey 2005) and generation time is 1.24 years. As an early-maturing 
species, with fast growth rates and high productivity, dwarf seahorse 
subpopulations are highly dynamic and likely able to respond quickly to 
conservation actions or short-term threats. However, this brief life 
history strategy makes it difficult to forecast the response to long-
term threats, such as climate change, that extend over several decades. 
The SRT was unsure how a short-lived species would be able to adapt to 
slowly changing habitats associated with climate change. The SRT 
discussed whether the impacts of known threats could be confidently 
predicted over timeframes of several generations.
    The SRT believed the foreseeable future should include several 
generation times and ultimately decided on approximately 8 generation 
times, or 10 years, as the SRT felt confident they could predict the 
impact of threats on the species over a decade. While the selected 
foreseeable future of 10 years is shorter than that estimated for other 
species, the brief and highly dynamic life history of the dwarf 
seahorse must be considered in determining an appropriate foreseeable 
future because, their rapid turnover and capacity for replacement 
limits our ability to reasonably predict the impact of longer-term 
threats on the species.
    The ability to determine and assess risk factors to a marine 
species is often limited when quantitative estimates of abundance and 
life history information are lacking. Therefore, in assessing threats 
and subsequent extinction risk of a data-limited species such as the 
dwarf seahorse, we include both qualitative and quantitative 
information. In assessing extinction risk to the dwarf seahorse, the 
SRT 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 (see https://www.fisheries.noaa.gov/resources/documents?sort_by=created&title=status+review for links to these 
reviews). 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.
    Using these concepts, the SRT evaluated extinction risk by 
assigning a risk score to each of the four demographic viability 
factors and five threats-based listing factors. The scoring was as 
follows: Very low risk = 1; low risk = 2; medium risk = 3; high risk = 
4; and very high risk = 5.
     Very low risk: It is unlikely that this factor contributes 
significantly to risk of extinction, either by itself or in combination 
with other demographic viability factors.
     Low risk: It is unlikely that this factor contributes 
significantly to current or long-term risk of extinction by itself, but 
there is some concern that it may, in combination with other 
demographic viability factors.
     Moderate risk: This factor contributes to the risk of 
extinction and may contribute to additional risk of extinction in 
combination with other factors.
     High risk: This factor contributes significantly to short-
term or long-term risk of extinction and is likely to be magnified by 
the combination with other factors.
     Very high risk: This factor by itself indicates danger of 
extinction in the near future and over the foreseeable future.
    SRT members were also asked to consider the potential interactions 
among demographic and listing factors. If the demographic or listing 
factor was ranked higher due to interactions with other demographic or 
listing factors, SRT members were asked to identify those factors that 
caused them to score the risk higher (or lower) than it would have been 
if it were considered independently.
    Finally, the SRT examined and discussed the independent responses 
from each team member for each demographic and listing factor to 
determine the overall risk of extinction (see Extinction Risk 
Determination below).

Demographic Risk Analysis

Abundance
    The best available information on dwarf seahorse abundance 
indicates that the species may still be present along the east coasts 
of Mexico and Texas and along both coasts of Florida. Lack of data from 
outside the United States

[[Page 45382]]

hindered the SRT's ability to analyze abundance trends in foreign 
locations. Within the United States, dwarf seahorse appears to be most 
common in Florida, though it is also present at a much lower level of 
abundance in south Texas. Outside of Florida and Texas, observations 
and records of the dwarf seahorse are historically uncommon. Seasonally 
low water temperatures establish geographic range boundaries, which 
likely contribute to the limited number of records of the dwarf 
seahorse in waters of the northern Gulf coast (Florida panhandle to 
north Texas). Additionally, limited seagrass habitat along the northern 
Gulf coast, both historically and currently, also likely restricts 
dwarf seahorse in this region. There are three sources that can be used 
to estimate the species relative abundance: U.S. Geological Survey 
data, the Florida Fish Wildlife Conservation Commission (FWC) Fisheries 
Independent Monitoring (FIM) program in Florida, and the Texas Parks 
and Wildlife Department (TPWD) monitoring program in Texas. 
Additionally, a population modeling study by Carlson et al. (2019) 
provides insight into the abundance of dwarf seahorse in Florida and 
the potential changes to this population in the context of ongoing 
threats.
    The FWC FIM program provided survey data for several estuarine 
areas in Florida including Apalachicola Bay (1998-2016), Cedar Key 
(1996-2016), Tampa Bay (1996-2016), Sarasota Bay (2009-2016), Charlotte 
Harbor (1996-2016), Florida Bay (2006-2009), and Indian River Lagoon 
(1996-2016). FIM program data indicate that dwarf seahorses are not 
abundant in northern Florida and have not been encountered in the 
Florida Keys National Marine Sanctuary. Surveys conducted within 
estuaries of northern Florida found that the species is rare in 
Apalachicola Bay and Cedar Key, and has never been recorded in 
Choctawhatchee Bay or Northeast Florida. In the Indian River Lagoon, on 
Florida's east coast, relative abundance was low throughout the survey 
period (1996-2016), with no individuals recorded from 2011-2013. The 
decline of the dwarf seahorse in the Indian River Lagoon could be the 
direct result of recent HABs in the estuary (SJRWMD, 2012; FWC, 2014). 
During the late 1980s and early 1990s, significant HABs in Florida Bay 
resulted in massive seagrass die-offs and reductions in dwarf seahorse 
abundance (Matheson Jr. et al. 1999). However, survey data from 2006-
2009 suggest that the dwarf seahorse was relatively abundant in Florida 
Bay when compared to other species and locations (FWC FIM unpublished 
data).
    In Florida, the species appears to be most abundant in five 
estuaries: Charlotte Harbor, Tampa Bay, Sarasota Bay, Biscayne Bay, and 
Florida Bay (Figures 3 and 4 in NMFS 2020). The SRT believes these five 
estuaries comprise the core area of abundance critical to the 
population. Although long-term dwarf seahorse abundance has declined 
from historical levels, abundance has remained stable at a lower level 
since 2009 when the trip limit regulations went into effect (FWC FIM 
unpublished data). The best available information on the dwarf 
seahorse's status suggests that Florida Bay has the highest relative 
abundance of the dwarf seahorse.
    Retrospective population projections provided in the Carlson et al. 
(2019) population viability assessment (PVA) of dwarf seahorses 
estimated male subpopulation sizes over the past 15-20 years using the 
empirical trends in seagrass coverage and occurrences of major 
stochastic events. Carlson et al. (2019) estimated subpopulations in 
2016 ranging from 15,258 in Cedar Key to 9,910,752 in Florida Bay. We 
compared the Carlson et al. (2019) estimated annual subpopulation sizes 
to the relative abundance indices from the FWC FIM small seine surveys 
for Cedar Key, Charlotte Harbor, Tampa Bay and Indian River Lagoon 
(Figure 18 in NMFS 2020). Modeled subpopulation sizes from the PVA did 
not track the trends in relative abundance reported by FWC early in the 
time series. The poor fit between modeled and reported data early in 
the time series was likely a result of the conservative initial 
population estimates in Carlson et al. (2019). However, the modeled 
data appeared to equilibrate and become more representative mid-way 
through the time series as indicated by similar patterns in trends 
between the modeled and reported data.
    The general agreement in recent trends suggests the PVA model 
captured the primary drivers of dwarf seahorse abundance. Additionally, 
the PVA results suggest that even with conservative assumptions 
regarding initial population sizes for the different subpopulations, 
carrying capacity, sex ratio, and age at maturity, the dwarf seahorse 
population numbers in the tens of millions in Florida waters (Carlson 
et al. 2019). Dwarf seahorse subpopulation densities (N/m\2\), which 
were derived by dividing Carlson et al. (2019) subpopulation estimates 
by total subregion seagrass habitat areas, are significantly lower than 
those empirically observed, suggesting the Carlson et al. (2019) PVA is 
conservative in its assessment of total population size (see Table 2 in 
Carlson et al. 2019; Rose et al. 2019, Figures 3 & 4 in NMFS 2020). 
Similarly, multiplication of recent density estimates for Tampa Bay 
(0.139 N/m\2\--Rose et al. 2019; 0.095 N/m\2\--Masonjones et al. 2019) 
and Florida Bay (0.00392 N/m\2\ in seines and 0.00462 N/m\2\ in 
trawls--FWC FIM unpublished data) by the most recent estimates of 
seagrass habitat area in Tampa Bay (2014) and Florida Bay (2010-2011), 
respectively, provided estimates in the range of 15.5-22.6 million 
dwarf seahorses in Tampa Bay and between 6.0-7.1 million dwarf 
seahorses in Florida Bay. This analytical approach could overestimate 
seahorse abundance if the density estimates were generated from areas 
of localized dwarf seahorse abundance. However, density estimates are 
influenced by catchability, which varies between sampling gears. Dwarf 
seahorse densities derived from FIM catch-per-unit effort (CPUE) in 
Tampa Bay for 2009 were orders of magnitude smaller for bag seine and 
otter trawl, respectively (0.000402 N/m\2\ and 0.0000125 N/m\2\) than 
those derived by Rose et al. (2019). These nominal CPUEs are 2.9 
percent and 0.1 percent of the densities reported by Rose et al. (2019) 
for the same time period using specialized gears for sampling dwarf 
seahorse. Thus, population sizes of dwarf seahorse based on expanding 
nominal FIM CPUE to seagrass area could be underestimates if animals 
are uniformly distributed within seagrass habitats across the FIM 
sampling domain. The difference in estimated abundance between Tampa 
Bay and Florida Bay presented above is likely attributable to sampling 
design; the Tampa Bay studies by Masonjones et al. (2019) and Rose et 
al. (2019) were actively targeting dwarf seahorses using specialized 
gears in an area believed to contain high densities, whereas the 
Florida Bay study was a general nekton survey using less efficient 
gears (trawls and seines) for collecting dwarf seahorse. Importantly, 
this approach does suggest that field estimates of abundance, when 
expanded for the full range of dwarf seahorse habitats, can greatly 
exceed the estimates generated by the Carlson et al. (2019) modeling 
approach.
    In Texas, dwarf seahorse abundance is low and restricted to the 
central and southern coastal systems including Aransas Bay, Corpus 
Christi Bay, San Antonio Bay, and the Upper and Lower Laguna Madre. The 
species has not been recorded in TPWD surveys conducted in

[[Page 45383]]

Galveston, Matagorda, and East Matagorda Bay systems. Of the bays where 
dwarf seahorses have been recorded, relative abundance is highest in 
Upper Laguna Madre, though abundance is still very low within this 
system compared to the Florida estuaries. Data series for the other 
bays (Aransas, Corpus Christi, San Antonio, and Lower Laguna Madre) 
have fewer than 10 records each, and therefore the SRT was unable to 
discern population trends. The SRT believes that Upper Laguna Madre is 
likely the core area of abundance for the southwestern portion of the 
species range within U.S. waters.
    Populations with very low abundance that occur over a limited 
geographic scale are more likely to be impacted by stochastic events 
such as HABs or extreme cold weather events. Recolonization and 
recovery is dependent on the ability of surrounding populations to 
provide recruits to the depleted area. In some cases, a population may 
have suffered a stochastic event and not been encountered in surveys 
for several years before eventually returning to the area. Periodic 
HABs continue to occur in Texas lagoons, but some bays, like Laguna 
Madre, have consistently recorded dwarf seahorses in surveys indicating 
that subpopulations can tolerate stochasticity in their environment. 
Regardless, it is not prudent to base an assessment of risk to species 
abundance on such few observations as reported from Texas.
    Commercial harvest and bycatch of the dwarf seahorse in Florida is 
a factor that impacts species abundance. The dwarf seahorse is targeted 
by the commercial ornamental fishery to be sold for aquarium markets. 
According to dealer reports, harvest appears to be focused from Tampa 
Bay to Fort Myers and from Florida Bay to Miami (FWC, 2012). However, 
commercial harvest is prohibited within the Everglades National Park, 
which encompasses a significant portion of Florida Bay. The dwarf 
seahorse is also among those species likely captured by non-selective 
trawl fishing gear targeting bait shrimp, because this trawling often 
occurs in seagrass habitat. The subpopulations in Charlotte Harbor and 
Tampa Bay have been variable since surveys began in 1996, but have 
stabilized since new regulations limiting harvest were adopted in 2009. 
Because few, if any, reported large-scale stochastic events have 
occurred over the past two decades within these systems, it is 
reasonable to infer that high levels of commercial harvest prior to the 
2009 trip limit likely caused at least a portion of the observed 
historical declines in Charlotte Harbor and Tampa Bay (Figures 12 & 13 
in NMFS 2020).
    The best available information indicates that habitat loss and 
degradation, stochastic events (HABs and extreme cold weather events), 
and commercial harvest are factors that impact dwarf seahorse 
abundance. However, the species appears to be at risk of local 
extirpation only where populations have very low abundance or are 
isolated due to the distance between habitat patches or estuary 
systems.
    Based on the above information, the SRT members scored the present 
risk of dwarf seahorse extinction based on abundance from 2 to 3, with 
a mean of 2.3 and a mode of 2. The team concluded that, based on the 
population estimate resulting from the population viability model, 
which shows stable or increasing subpopulations in most areas, the 
abundance of dwarf seahorse presents a low risk of extinction and the 
population is robust enough to withstand threats currently facing the 
species. This result is similar to the International Union for 
Conservation of Nature (IUCN) Red List assessment, which identified 
dwarf seahorse as a species of ``least concern'' in terms of its threat 
status (Masonjones et al. 2017). Although most subpopulations showed 
stable or increasing abundance and the team expected these patterns to 
continue into the foreseeable future based on the predictive modeling 
in Carlson et al. (2019), an increase in the frequency, duration, or 
scale of stochastic events into the future may increase extinction 
risk. It was unclear to the SRT whether HABs and cold weather events 
would increase in frequency and magnitude over the 10-year foreseeable 
future, because the events are stochastic in nature and their causes 
are poorly understood. Several conservative 10-year forecasts were 
modeled to encompass the extinction risk associated with the 
possibility of an increasing frequency and magnitude of these 
stochastic events. When considering the contribution of abundance to 
the risk of extinction over the foreseeable future, the team scored 
abundance as a moderate risk (3), given the uncertainty associated with 
increased potential for stochastic events.
Population Growth Rate and Productivity
    The life history characteristics of the dwarf seahorse (i.e., early 
age at maturity, rapid growth, high fecundity, and parental care) 
suggest that this species has a relatively high intrinsic rate of 
population increase (more births than deaths per generation time; 
Rmax = 1.49 yr-1) and high compensatory capacity 
(ability of a population to positively respond to changes in its 
density) (Kindsvater et al. 2016). The dwarf seahorse has relatively 
high fecundity compared to other seahorse species, though fecundity is 
much lower than other teleosts. Current demographic analysis suggest 
that healthy subpopulations have high intrinsic rates of population 
increase and would be able to tolerate high levels of direct and 
indirect mortality. However, the species also has complex courtship 
behaviors and is constrained by its habitat specificity and small home 
range. With the dwarf seahorse's complex reproductive behaviors, many 
factors (e.g., stochastic events, directed fishing, bycatch) could 
disrupt courtship and mating and consequently reduce productivity.
    The SRT believes that the dwarf seahorse subpopulations in 
Charlotte Harbor, Sarasota Bay, Tampa Bay, Florida Bay, and Biscayne 
Bay are more productive than those of other estuaries and bays within 
the species' range. The best available information suggests that 
several other estuaries and bay systems in Florida and Texas have 
subpopulations which may be at risk of an Allee effect (i.e., inability 
to find a mate and subsequently low levels of population growth from 
future recruitment), though these are all systems along the fringe of 
the dwarf seahorse range and therefore may have naturally low 
abundance.
    The SRT considered scenarios developed by Carlson et al. (2019) for 
dwarf seahorse abundance in five bay systems: Cedar Key, Tampa Bay, 
Charlotte Harbor, Florida Bay and northern Indian River Lagoon (Figure 
5 in NMFS 2020). Scenarios were initiated at the earliest time data 
were available on the coverage of the seagrass canopy from Yarbro and 
Carlson (2016) taking into account changes in seagrass density, 
commercial harvest, bycatch and mortality related to HABs and cold 
temperature events. Three of the five subpopulations (Tampa Bay, 
Charlotte Harbor, Florida Bay) slightly increased in abundance (3-8 
percent), whereas the Cedar Key and northern Indian River Lagoon 
subpopulations did not increase in abundance.
    Carlson et al. (2019) also explored future scenarios to test the 
effect of the most likely threats to dwarf seahorse (Figure 20 in NMFS 
2020). As the harvest of dwarf seahorse by the Marine Life fishery has 
been limited, the greatest threats to future seahorse subpopulations 
include the loss of seagrass habitat, and increased harmful algal 
blooms, which can cause acute

[[Page 45384]]

mortality. Carlson et al. (2019) explored optimistic scenarios 
(increased seagrass coverage and current levels) and pessimistic 
scenarios (increased rates of mortality, loss of seagrass habitat and 
likelihood of HABs increasing from historically observed levels). The 
population was projected forward 10 years. Starting conditions for 
these projections were conservatively assumed at the lower 5 or 10 
percent quantiles from bootstrapped empirical estimates of abundance 
(see Table 2 in Carlson et al. 2019). Projected stock trajectories 
under potential future conditions were mostly stable in Cedar Key, 
declining in Northern Indian River Lagoon, and generally increasing 
under the vast majority of scenarios for the other three locations 
(Figure 13 in NMFS 2020). Only the most pessimistic scenario for Indian 
River Lagoon resulted in extirpation of any subpopulation within 10 
years.
    Scenarios testing the effects of HABs accompanied by reduced 
seagrass habitat affected all subpopulations' abilities to grow. The 
subpopulation to be most affected was the Indian River Lagoon, which 
experienced significant declines in abundance. Abundance of dwarf 
seahorse in Indian River Lagoon declined from a starting size of about 
86,000 males to less than 6,000 in 10 years. Other subpopulations were 
able to maintain their baseline levels of abundance despite losses of 
habitat.
    The SRT determined that population growth rate and productivity of 
dwarf seahorse present a low risk of extinction to the species. Each 
member of the team scored this demographic variable as a level 2 risk, 
both currently and over the foreseeable future.
Spatial Structure/Connectivity
    The dwarf seahorse has low mobility, occupying a limited activity 
space and small home range within a specific habitat (seagrasses). 
These life history traits suggest that the species is not likely to 
disperse actively. However, movement by passive dispersal occurs as 
seahorses use their prehensile tail to hold on to seagrass or 
macroalgae which are carried by currents (Foster and Vincent 2004; 
Masonjones et al. 2010; Fedrizzi et al. 2015). A population genetics 
study on Hippocampus kuda in the Philippines suggested colonization of 
distant habitats by a small number of founding individuals may be 
common in seahorses associated with the H. kuda complex (Teske et al. 
2005).
    The species' short lifespan, narrow habitat preference, and low 
mobility increase extinction vulnerability as the dwarf seahorse is 
susceptible to population fragmentation and loss of population 
connectivity. Successful repopulation or colonization may depend on a 
sufficient number of individuals emigrating to a habitat containing 
seagrass to establish themselves. It is essential that seagrass habitat 
patches exist between subpopulations as dispersal capabilities are 
restricted by the availability of seagrass habitat. Historically, the 
dwarf seahorse has shown that it can recover from stochastic events 
(HABs and extreme cold weather events) where subpopulations have been 
impacted or even temporarily extirpated, but low relative abundance in 
some areas may limit repopulation.
    Based on the best available information on the spatial structure/
connectivity of dwarf seahorse subpopulations, the SRT believes this 
demographic variable presents a moderate extinction risk both now and 
in the foreseeable future. Team scores ranged from 2 to 3, with a mean 
of 2.7 and a mode of 3. Differences in scores were largely a reflection 
of personal thoughts on how far dwarf seahorses may disperse via 
rafting, and thus how connected the populations could be.
Diversity
    The loss of diversity can reduce a species' reproductive fitness, 
fecundity, and survival, thereby contributing to declines in abundance 
and population growth rate and increasing species extinction risk 
(Gilpin and Soule, 1986). There is no indication that the dwarf 
seahorse is at risk due to a significant change or loss of variation in 
life history characteristics, population demography, morphology, 
behavior, or genetics.
    However, the SRT considered diversity to present a moderate 
extinction risk to dwarf seahorses both now (range 2-3, mode = 3) and 
in the foreseeable future (range 2-3, mode 3). The team considered this 
a moderate risk given the lack of genetic information, particularly 
from Texas, and how that population may relate to the Florida 
population. Similarly, Fedrizzi et al. (2015) indicated population 
structuring in which the Panhandle represents a separate population 
from other areas of Florida. Given the large distance between the 
subpopulations in the Florida panhandle and other parts of Florida the 
team also expressed concern over the transfer of genetic material. 
Expanding the research of Fedrizzi et al. (2015) to include dwarf 
seahorses from Texas and Mexico could provide additional information on 
the diversity of dwarf seahorse, the relationship among those outside 
of Florida, and whether additional regulatory measures may be 
necessary.
Summary of Demographic Risk Analysis
    The SRT found that threats such as habitat loss or degradation and 
overutilization may interact with the dwarf seahorse's life history 
traits to increase the species' extinction risk. The dwarf seahorse's 
habitat preference and low mobility could increase the species' 
ecological vulnerability, as the species may be slow to recolonize 
depleted areas. Similarly, patchy spatial distributions in combination 
with low relative population abundance (relative to historical levels) 
make the species susceptible to habitat degradation and 
overexploitation. Life history traits, such as complex reproductive 
behavior and monogamous mating, may also increase the species' 
vulnerability. However, the species' ability to mature early and 
reproduce multiple times throughout a prolonged breeding season offsets 
much of the vulnerability.

Threats-Based Analysis

The Present or Threatened Destruction, Modification, or Curtailment of 
Its Habitat or Range
    The SRT considered the destruction or modification of habitat to be 
the largest threat facing dwarf seahorse both now and into the 
foreseeable future. As discussed in the Status Review Report (NMFS 
2020), there are a number of threats impacting seagrass habitats upon 
which dwarf seahorse rely, including water quality, damage from vessels 
and trawling, and climate change. Regulations and educational programs 
have and continue to be implemented in an attempt to reduce impacts 
from water quality, vessels, and trawling. In light of the long-term 
HAB in the Indian River Lagoon resulting in large-scale losses of 
seagrasses and the collapse of the dwarf seahorse subpopulation there, 
the SRT was particularly concerned with HABs, their interaction with 
water quality, and their potential to negatively affect dwarf seahorse. 
One of the most severe HABs on the west coast of Florida occurred in 
2005, with substantial spread of red tide into Tampa Bay (see Figure 1b 
in Flaherty & Landsberg 2011). FIM data showed a substantial (-71 
percent) but statistically insignificant decline in relative abundance 
in 2005, with a substantial (+110 percent) recovery in 2006. Another 
HAB was present along the west coast of Florida between Charlotte 
Harbor and Tampa Bay during the summer and fall of 2018. HAB monitoring 
data indicate Karenia brevis (red tide) did not enter Tampa Bay or 
Charlotte Harbor (Figure 21 in NFMS

[[Page 45385]]

2020), which may have spared dwarf seahorses inhabiting these 
estuaries. Subsequent dwarf seahorse sampling in Tampa Bay during 2019 
indicates a robust dwarf seahorse population in Old Tampa Bay and Ft. 
DeSoto areas (H. Masonjones, University of Tampa, pers. comm. to Adam 
Brame, NOAA Fisheries, on October 13, 2019). The 2018 HAB did not 
affect Florida Bay, where surveys and model simulations suggest dwarf 
seahorses are found in the highest abundance.
    The SRT was also concerned about the impact of climate change 
affecting seagrass habitat into the future. Climate change is expected 
to impact seagrass habitat, though the temporal rate and degree to 
which this occurs is not known with certainty. The Status Review 
indicates that thermal tolerance of seagrasses and rising sea levels 
may affect future distribution and meadow health, while warming 
seawater temperatures could increase the available habitat for dwarf 
seahorses along the northern Gulf of Mexico. Based on the above 
information, the team scored the present destruction or modification of 
habitat as a moderate risk for dwarf seahorse, with all team members 
giving it a score of 3. Considering the uncertainty associated with 
climate change and HABs in the future, the team scored this threat 
slightly higher when considering it over the foreseeable future, with 
two members giving it a score of 4 and one team member giving it a 
score of 3.
Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes
    The commercial harvest of the dwarf seahorse is restricted to 
Florida, but is considered by the SRT to be the second greatest threat 
to the species after habitat loss and degradation. The dwarf seahorse 
is harvested largely for the aquarium markets and removals have 
resulted in declines in local subpopulation abundance since the early 
1990s. In general, seahorses are one of the most popular and heavily 
exploited marine ornamentals harvested in Florida. Dwarf seahorse 
landings are significantly higher than other seahorse species; landings 
data shows that seahorse harvest consists almost solely of dwarf 
seahorse.
    Data indicate that over a 25-year timeframe, dwarf seahorse 
landings have fluctuated with tens of thousands being harvested 
annually. Historical declines in abundance observed in Charlotte Harbor 
and Tampa Bay suggest that harvest may be impacting these core 
subpopulations. A 2009 trip limit regulation has reduced the harvest of 
dwarf seahorses and the population appears to have stabilized as a 
result (Figures 3 and 5 in NMFS 2020). Additionally, a significant 
portion of Florida Bay is protected by the prohibition on commercial 
fishing within Everglades National Park boundaries. The protection 
against commercial harvest and bycatch within this system likely played 
a significant role in the species' ability to recover from the HABs 
that impacted Florida Bay during the late 1980s and early 1990s.
    While the use of any net with a mesh area exceeding 500 square feet 
(46.5 square meters) is prohibited in nearshore and inshore waters of 
Florida (Florida 68B-4.0081(3)(e)), a bait-shrimp fishery operates 
within these boundaries. This fishery relies upon small trawls to 
collect shrimp for bait, and, given this fishery operates in seagrass 
habitat, it is reasonable to infer that dwarf seahorse are removed as 
bycatch. Seahorses may be more vulnerable to injuries, mortality, and 
disruption of reproduction in habitats that are disturbed by heavy 
trawls deployed for longer periods and over greater areas (Baum et al. 
2003). Baum et al. (2003) analyzed bycatch of the lined seahorse 
(Hippocampus erectus) in the bait-shrimp trawl fishery and estimated 
about 72,000 seahorses were incidentally caught per year. However, this 
study reported only two dwarf seahorses were captured during the study 
period. In developing bycatch estimates for use in their population 
viability model, Carlson et al. (2019) used the ratio of dwarf seahorse 
caught to lined seahorse caught and estimated that 157 dwarf seahorses 
are incidentally caught per year.
    The SRT assumes that demand for the dwarf seahorse in the marine 
ornamental fishery and aquarium markets will continue. The extent to 
which heavy commercial harvest is impacting dwarf seahorse populations 
in Florida is largely unknown, although there are some indications that 
overharvest may be impacting populations in Charlotte Harbor and Tampa 
Bay. In response to the listing petition and the subsequent data 
request by NMFS, the State of Florida considered new regulations, which 
included time-area closures and a 200 seahorses per trip limit. NMFS 
analyzed the potential effects of the proposed regulations and 
determined the area closure, the 200 seahorses per trip limit, and an 
April-June closed season could, cumulatively, reduce harvest by 40-48 
percent (NMFS 2015). Despite the results of the analysis, the State of 
Florida did not adopt the new regulations, as the state believed the 
current trip limit of 400 seahorses per day was sufficient for 
sustainably managing the wild populations of seahorses. While the SRT 
believes that the dwarf seahorse population is likely still being 
negatively impacted by harvest under the current regulations, removals 
since 2009 have declined by 55 percent, and the relative abundance 
trend information since 2009 is stable (as an indirect indicator of 
status) in areas where dwarf seahorses are significantly harvested 
(e.g., southwest Florida and southeast Florida, including the Florida 
Keys). Dwarf seahorses are characterized by rapid growth, early age at 
maturity, and short generation time, all of which collectively indicate 
that the species has high intrinsic rates of population increase. This 
suggests that populations can recover from declines following a 
reduction in fishing effort (Curtis et al. 2008).
    The SRT concluded that the species is currently at a low to 
moderate risk due to overexploitation from commercial harvest, with 
scores that ranged between 2 and 3, with a mean of 2.3 and a mode of 2. 
Given that the team considered similar rates of utilization in the 
future, scores were the same when considering the threat over the 
foreseeable future. The scores also remained the same when considered 
in combination with other threats, such as lack of adequate existing 
regulatory mechanisms.
Disease and Predation
    The SRT determined that disease and predation present a very low 
extinction risk to dwarf seahorse. The team was not able to find 
documentation of disease affecting wild subpopulations of dwarf 
seahorse. With respect to predation, the team assumed mortality rates 
from predation are likely higher for juvenile seahorses than adults. 
The dwarf seahorse is presumed to have few predators and is likely only 
opportunistically predated upon by fishes, crabs, and wading birds. The 
dwarf seahorse's excellent camouflage is well-adapted for the species' 
ecological niche and likely reduces the level of predation on the 
species.
    All members of the SRT scored disease and predation as a 1, both 
now and over the foreseeable future, which indicates a very low risk in 
the ERA.
Inadequacy of Existing Regulatory Mechanisms
    With respect to inadequacy of existing regulatory mechanisms, there 
are only three regulations that relate to Hippocampus species in the 
United States. Internationally, only Bermuda has a regulation 
pertaining to seahorses,

[[Page 45386]]

and it focuses only on lined and longsnout seahorses, as the dwarf 
seahorse has been extirpated there. The SRT was not aware of any 
seahorse regulations in The Bahamas or Cuba.
    Within the state of Florida, the FWC regulates fishing effort in 
both the commercial marine life fishery, which includes marine 
ornamentals like the dwarf seahorse (68B-42, F.A.C.) and the 
recreational fishery. The commercial regulations include requirements 
for specific fishing licenses and tiered endorsements, as well as a 
commercial trip limit of 400 dwarf seahorses per person or vessel per 
day, whichever is less (68B-42.006, F.A.C.). There is no cap on the 
total annual take of dwarf seahorses, and there are no seasonal 
restrictions or closures. However, entry is limited into the commercial 
marine life fishery for ornamentals. From 2010-2014, on average, 19 
permit holders have reported Florida dwarf seahorse harvest. 
Enforcement of the trip limit regulation has been problematic as at 
least one commercial harvester has continued to exceed the 400 dwarf 
seahorses limit since its inception. This harvester exceeded the trip 
limit 26 trips out of 80 between 2010 and 2015 (NMFS 2015). The State 
of Florida also regulates recreational harvest of dwarf seahorse (daily 
bag limit of up to five per person per day) and bycatch of dwarf 
seahorses associated with the inshore bait shrimp fishery (also limited 
by the recreational bag limit). Because there is no reporting 
associated with recreational limits, the SRT is unsure of the impact 
these regulations have on the dwarf seahorse population.
    The assessment of individual species and fishing effort are 
necessary to determine whether existing regulations are likely to be 
effective at maintaining the sustainability of the resources. To date, 
however, the commercial removal of dwarf seahorses and its impact on 
the population has not been assessed. The SRT was unable to determine 
exactly how the daily bag limit (400 dwarf seahorses per person per 
day) was established, its ability to prevent overharvest, or how 
effective it will be at achieving long-term sustainability. However, 
the 2009 bag limit regulation seems to have stabilized the population 
since implementation.
    The second regulatory mechanism that may affect seahorses 
(Hippocampus spp.) is the Convention on International Trade in 
Endangered Species of Wild Fauna and Flora (CITES)--an international 
agreement between governments established with the aim of ensuring that 
international trade in specimens of wild animals and plants does not 
threaten their survival. Seahorses are listed under Appendix II of 
CITES. Appendix II includes species that are not necessarily threatened 
with extinction, but for which trade must be controlled in order to 
avoid utilization incompatible with their survival. International trade 
of Appendix II species is permitted when export permits are granted 
from the country of origin. In order to issue an export permit, the 
exporting country must find that the animals were legally obtained and 
their export will not be detrimental to the survival of the species in 
the wild (referred to as a ``non-detriment finding''). Millions of 
seahorses are traded internationally each year, although only a small 
percentage of these are dwarf seahorses, and the CITES listing has not 
curbed this trade (Foster et al. 2014). Almost all the dwarf seahorses 
harvested from the wild populations in the United States remain in U.S. 
markets and therefore are not subject to the CITES regulation of trade 
under Appendix II. Dwarf seahorses represent approximately 0.01 percent 
of international trade, and over a 10-year period only 2,190 dwarf 
seahorses were exported from the United States, with 1,500 of those 
being captive-bred (USFWS 2014).
    The third regulatory factor that provides protections for seahorses 
is the listing of dwarf seahorse as a species subject to ``Special 
Protection'' under Mexican law. This limits any removal of the species 
to what is allowed under the rules of the Mexican General Law of 
Wildlife (Diaz 2013), which establishes the conditions for capture, and 
transport permits, and authorizations (Bruckner et al. 2005). The SRT 
is unsure of the adequacy of this regulation at this time.
    The SRT expects that demand for the dwarf seahorse in the marine 
ornamental fishery and aquarium markets will continue into the future. 
The extent to which current regulations are adequate at protecting the 
dwarf seahorse population was difficult to evaluate. The SRT concluded 
that the lack of regulatory mechanisms intended to control harvest, 
particularly commercial harvest, is likely having detrimental effects 
on population abundance and productivity. However, the 2009 regulation 
limiting commercial harvest to 400 seahorses per person or per vessel 
per day, whichever is less, seems to have stabilized the population. In 
combination with time-area closures associated with the marine life 
fishery, the limited entry into the fishery, and export regulations 
associated with CITES, the team concluded that inadequacy of regulatory 
mechanisms presents a low extinction risk (mode = 2). Given the team's 
belief that these regulations will remain in place and that they will 
continue to affect harvest in a similar manner into the future, the 
scores remained unchanged when considering this threat over the 
foreseeable future.
Other Natural or Manmade Factors Affecting Its Continued Existence
    The Status Review Report (NMFS 2020) identified several potential 
natural or man-made factors that could serve as potential threats to 
the dwarf seahorse. These included the species' life history strategy, 
anthropogenic noise, oil spills, and high-impact storm events. The SRT 
evaluated the potential impact of these threats on the dwarf seahorse, 
but did not find that any of these other threats are likely to be a 
source of high extinction risk to the dwarf seahorse. The dwarf 
seahorse life history strategy is well suited to respond to periodic 
declines associated with stochastic events. The Deepwater Horizon oil 
spill occurred far from the core dwarf seahorse population in south and 
southwest Florida and was not known to affect seagrass habitat outside 
of the area around the Chandeleur Islands where dwarf seahorses are 
rare. While future oil spills could impact dwarf seahorses or their 
habitat, the majority of oil and gas exploration occurs in the central 
and western portions of the Gulf of Mexico, and oil would need to be 
transported great distances to reach the nearshore waters of Florida 
where dwarf seahorses are most abundant. Data are insufficient to 
determine how anthropogenic noise affects dwarf seahorses, and life 
history and future studies may be necessary to address this potential 
threat. Lastly, weather events have the potential to impact dwarf 
seahorses, but these are expected to be short-term perturbations that 
the species is capable of quickly responding to. The SRT ranked this 
category of threats as a very low risk both currently and in the 
foreseeable future, with all team members scoring this factor a 1.

Extinction Risk Determination

    Guided by the results from the demographics risk analysis as well 
as the threats-based analysis, the SRT members used their informed 
professional judgment to make an overall extinction risk determination 
for the species. For these analyses, the SRT defined three levels of 
extinction risk:
     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

[[Page 45387]]

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 imminent and substantial demographic risks;
     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 (see description of ``High risk'' 
above). A species may be at moderate risk of extinction due to 
projected threats or declining trends in abundance, productivity, 
spatial structure, or diversity. The appropriate time horizon for 
evaluating whether a species will be at high risk in the foreseeable 
future depends on various case-specific and species-specific factors. 
For example, the time horizon may reflect certain life history 
characteristics (e.g., long generation time or late age at maturity) 
and may also reflect the timeframe or rate over which identified 
threats are likely to impact the biological status of the species 
(e.g., the rate of disease spread); and
     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'' above). A species may be at 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.
    To allow individuals to express uncertainty in determining the 
overall level of extinction risk facing the dwarf seahorse, the SRT 
adopted the ``likelihood point'' method, which has been used in 
previous status reviews (e.g., Pacific salmon, Southern Resident Killer 
Whale, Puget Sound Rockfish, Pacific herring, and black abalone) to 
structure the team's thinking and express levels of uncertainty in 
assigning threat risk categories. For this approach, each team member 
distributed 10 ``likelihood points'' among the three extinction risk 
levels. After scores were provided, the team discussed the range of 
risk level perspectives for the species, and the supporting data on 
which the perspectives were based, and each member was given the 
opportunity to revise scores if desired after the discussion. The 
scores were then tallied (mode, median, range), discussed, and 
summarized for the species.
    Finally, the SRT did not make recommendations as to whether the 
dwarf seahorse should be listed as threatened or endangered. Rather, 
the SRT drew scientific conclusions about the overall risk of 
extinction faced by this species under present conditions and in the 
foreseeable future, based on an evaluation of the species' demographic 
viability factors and assessment of threats.
    The best available information indicates that within the United 
States dwarf seahorses occur in Florida and to a lesser extent in south 
Texas, but do not appear to extend into the northern Gulf of Mexico 
(i.e., Alabama, Mississippi, and Louisiana), as previously believed. 
The SRT acknowledged that there is a lack of abundance data in the 
northern Gulf of Mexico, but found that, because the species is 
temperature-limited, and due to the seasonal cold water temperatures in 
that region (Figure 8 of NMFS 2020), it is unlikely that dwarf seahorse 
was ever common in the northern Gulf of Mexico. The SRT determined that 
there is evidence of a historical decrease in abundance, especially in 
areas where dwarf seahorses are naturally abundant. However, over the 
past decade the most productive subpopulations appear stable or appear 
to be increasing in their abundance, despite the threats they face. 
Current regulations and the rebuilding of seagrass habitat have 
stabilized the populations. The team acknowledged that uncertainty in 
the frequency, duration, and scale of stochastic events (HABs and 
extreme cold weather events) could affect the population trend into the 
foreseeable future and increase extinction risk, but ultimately, based 
on the predictive analyses provided in Carlson et al. (2019), the team 
believed that the population is robust enough to handle this threat.
    Outside of the United States, data on abundance and population 
trends are lacking. Evidence suggests the species is present along the 
east coast of Mexico, but without abundance data the SRT was unable to 
make further conclusions. Therefore, the team made conclusions based 
solely on the best available data from within the United States.
    The SRT had concerns regarding the level of commercial harvest, 
bycatch, and lack of regulatory mechanisms, and determined that these 
threats are likely having effects on the species--especially on those 
local subpopulations that occur in some of the most heavily exploited 
areas. In addition, overutilization will serve to exacerbate the 
demographic risks currently faced by the species. However, the SRT 
determined that habitat degradation (i.e., HABs and coastal 
construction), projected habitat losses due to sea level rise, and 
ocean warming resulting from climate change were the most significant 
threats to the species. The predicted losses of seagrass habitat due to 
climate change combined with the prolonged commercial harvest may 
increase the species demographic risks, as impacted populations may be 
limited in their abilities to recolonize depleted areas based on the 
dwarf seahorse's low mobility and narrow habitat preference. However, 
the team concluded that overall the species is at a low risk of 
extinction (19 out of a possible 30 likelihood points), as it is highly 
productive and faces only one high risk threat. The other remaining 11 
likelihood points were all assigned to the moderate risk category. We 
agree with the assessment provided by the SRT that the dwarf seahorse 
is at a low risk of extinction.

Significant Portion of Its Range

    As noted in the introduction above, the definitions of both 
``threatened'' and ``endangered'' under the ESA contain the term 
``significant portion of its range'' (SPR), and define SPR as an area 
smaller than the entire range of the species that must be considered 
when evaluating a species' risk of extinction. Under the final SPR 
Policy announced in July 2014, should we find that the species is of 
low extinction risk throughout its range (i.e., not warranted for 
listing), we must go on to consider whether the species may have a 
higher risk of extinction in a significant portion of its range (79 FR 
37577; July 1, 2014).
    As an initial step, we identified portions of the range that 
warranted further consideration based on analyses within the Status 
Review Report (NMFS 2020). The range of a species can theoretically be 
divided into portions in an infinite number of ways. However, as noted 
in the policy, there is no purpose to analyzing portions of the range 
that are not reasonably likely to be significant or in which a species 
is not likely to be endangered or threatened. To identify only those 
portions that warrant further consideration, we consider whether there 
is substantial information indicating that (1) the portions may be 
significant, and (2) the species may be in danger of extinction in 
those portions or is likely to become so within the foreseeable future. 
We emphasize that answering these questions in the affirmative is not a 
determination that the species is endangered or threatened throughout a 
SPR; rather, it is a step in determining

[[Page 45388]]

whether a more detailed analysis of the issue is required (79 FR 37578; 
July 1, 2014). Making this preliminary determination triggers a need 
for further review, but does not prejudge whether the portion actually 
meets these standards such that the species should be listed. If this 
preliminary determination identifies a particular portion or portions 
that may be both significant and may be threatened or endangered, those 
portions are then fully evaluated under the SPR authority to determine 
whether the members of the species in the portion in question are 
biologically significant to the species and whether the species is 
endangered or threatened in that portion of the range.
    The definition of ``significant'' in the SPR Policy was invalidated 
in two recent 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 portion, because in order for a portion to meet 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). Accordingly, while the SRT used the threshold 
identified in the policy, which was effective at the time the SRT met, 
NMFS did not rely on the definition of ``significant'' in the policy 
when making this 12-month finding. This is consistent with the second 
Desert Survivors case (336 F. Supp. 3d 1131, 1134-1136; N.D. CA August, 
2018), which vacated this definition without geographic limitation. As 
such, our analysis independently analyzed the biological significance 
of the members of the portion, drawing from the record developed by the 
SRT with respect to viability characteristics (i.e., abundance, 
productivity, spatial distribution, and genetic diversity) of the 
members of the portions, in determining if a portion was a significant 
portion of the species' range. We considered the contribution of the 
members in each portion to the viability of the taxon as a whole, given 
the current available information on abundance levels. We also 
considered how the contribution of the members in each portion affects 
the spatial distribution of the species (i.e., would there be a loss of 
connectivity, would there be a loss of genetic diversity, or would 
there be an impact on the population growth rate of the remainder of 
the species).
    Within the range of the dwarf seahorse we considered multiple 
population portions including: (1) South and southwest Florida, (2) 
east coast of Florida, (3) northwest Florida, (4) Texas, and (5) 
eastern Mexico. After a review of the best available information, we 
concluded that only the east coast of Florida and northwest Florida 
portions may have elevated risk of extinction relative to the species' 
status range-wide. The other portions considered were either not at 
risk of extinction (e.g., south and southwest Florida where abundance 
is high, subpopulations are stable, and seagrass communities are either 
stable or increasing) or there was insufficient data available to 
develop an opinion on extinction risk (Texas and eastern Mexico). 
Therefore, we proceeded to consider the biological significance of only 
the two portions with elevated extinction risk.
    The subpopulation of dwarf seahorses along the east coast of 
Florida, especially in Indian River Lagoon, appears to be at an 
elevated risk of extinction relative to the species' range-wide status. 
Under conservative starting conditions, the retrospective analysis 
showed this subpopulation has varied in abundance through time and 
persists at a stable but very low abundance as of 2016 (Carlson et al. 
2019). The projected PVA runs indicate the population is stable or 
slightly increasing under optimistic scenarios, but decreasing under 
all pessimistic scenarios, with the most pessimistic run leading to 
localized extinction (Carlson et al. 2019). The ongoing threat of poor 
water quality and HABs has drastically reduced seagrass coverage and in 
turn dwarf seahorse abundance in this portion of its range. If this 
subpopulation was lost, there would be a reduction in the geographic 
extent of the dwarf seahorse. However, this portion does not currently 
have the abundance or habitat capacity to buffer surrounding stocks 
against environmental threats and is not responsible for connecting 
other portions. The east coast of Florida subpopulation has been in 
decline for several years but we have not seen this result in a decline 
in the adjacent south and southwest Florida subpopulation, suggesting 
the contribution of the east coast is limited. While Fedrizzi et al. 
(2015) showed there is some gene flow between this portion and others 
via passive dispersal, the genetic contributions of the east coast 
portion to the rest of the population's range is limited by ocean 
currents and winds that dictate passive dispersal. Therefore we would 
not expect the loss of this portion to contribute significantly to a 
loss of genetic diversity, and the remaining population would contain 
enough diversity to allow for adaptations to changing environmental 
conditions. In conclusion, we determined that the east coast of Florida 
portion's contribution to the population in terms of abundance, spatial 
distribution, and diversity is of low biological importance and overall 
does not appear significant to the viability of the species. Thus we 
find the east coast of Florida does not represent a significant portion 
of the dwarf seahorse range.
    Dwarf seahorses in northwest Florida (including Apalachicola, Big 
Bend, Cedar Key, and St. Andrew's Bay) appear to be at a low risk of 
extinction despite low abundance and the threats facing the species 
within this portion of its range. Historically, this subpopulation has 
been far less abundant than other subpopulations, based on the 
retrospective analysis and fisheries surveys. Overall we find that the 
contribution that this stock makes to the species' abundance is low. 
This subpopulation is found on the northern periphery of the species 
range based on thermal tolerances and thus is most susceptible to 
mortality from cold weather events. A recent genetic analysis indicates 
the western-most portion of this subpopulation (Pensacola, Florida) is 
a separate population from the rest of the Florida population (Fedrizzi 
et al. 2015), but we are unsure of mixing along the boundary further to 
the south of this portion. If the northwest Florida portion was lost, 
dwarf seahorses rangewide would lose some potential genetic adaptation. 
However, this subpopulation is small in size and has limited genetic 
connectivity to the overall taxon. The remaining subpopulations would 
continue to provide genetic diversity to the species as whole. There is 
no evidence to indicate that the loss of genetic diversity from the 
northwest Florida portion of the dwarf seahorse range would result in 
the remaining portions lacking enough genetic diversity to allow for 
adaptations to changing environmental conditions. While it is possible 
that the unique genetic signature of the northwest

[[Page 45389]]

Florida portion conveys some type of adaptive potential to the species 
rangewide, we do not currently have evidence of this. In particular, it 
is unclear if this subpopulation is uniquely adapted genetically to 
tolerate colder conditions. The projected PVA runs indicate the 
subpopulation is generally stable (Carlson et al. 2019). Pessimistic 
PVA scenarios resulted in decreased abundance for this portion of the 
population, but not extinction (Carlson et al. 2019). Although this 
portion has some extinction risk, its low abundance and limited 
connectivity suggest it is not significant to the viability of the 
species overall.
    In summary, we find that there is no portion of the dwarf 
seahorse's range that is both significant to the species as a whole and 
endangered or threatened. After considering all the portions we believe 
that some portions (east coast of Florida and northwest Florida) carry 
an elevated risk of extinction relative to the status of the species 
range-wide; however, these portions are not biologically significant to 
the species. In contrast, the south and southwest Florida subpopulation 
appears to be biologically important to the continued viability of the 
overall species in terms of abundance, connectivity, and productivity, 
but this subpopulation is robust and not at risk of extinction now or 
in the foreseeable future. Thus, we find no reason to list this 
species, based on an analysis within a significant portion of its 
range.

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 have independently reviewed the best available 
scientific and commercial information, including the petitions, public 
comments submitted on the 90-day finding (77 FR 26478; May 4, 2012), 
the Status Review Report (NMFS 2020), 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 previously explained, we could not identify a 
significant portion of the species' range that is threatened or 
endangered. 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 conclude that the dwarf seahorse 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. Therefore, the 
dwarf seahorse 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.

References

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

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 proposed rule. Both the 
Status Review Report and the Peer Review Report can be found here: 
https://www.cio.noaa.gov/services_programs/prplans/ID411.html.

Authority

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

    Dated: July 22, 2020.
Samuel D. Rauch, III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.
[FR Doc. 2020-16335 Filed 7-27-20; 8:45 am]
BILLING CODE 3510-22-P