[Federal Register Volume 89, Number 106 (Friday, May 31, 2024)]
[Rules and Regulations]
[Pages 47089-47095]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-11767]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Parts 223 and 224

[Docket No. 240522-0144; RTID 0648-XR132]


Endangered and Threatened Wildlife; 90-Day Finding on a Petition 
To List the Delaware River Atlantic Sturgeon (Acipenser oxyrinchus 
oxyrinchus) Population as an Endangered Distinct Population Segment 
Under the Endangered Species Act

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

ACTION: Notification of 90-day finding.

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SUMMARY: We, NMFS, announce our 90-day finding on a petition to list 
the Delaware River population of Atlantic sturgeon as an endangered 
distinct population segment (DPS) of Atlantic sturgeon under the 
Endangered Species Act (ESA) and to designate critical habitat for the 
DPS. We find that the petition does not present substantial scientific 
or commercial information indicating that the petitioned actions may be 
warranted. Therefore, we are denying this petition.

DATES: This finding was made on May 31, 2024.

ADDRESSES: Copies of the petition and related materials are available 
from the NMFS website at https://www.fisheries.noaa.gov/national/endangered-species-conservation/negative-90-day-findings.

FOR FURTHER INFORMATION CONTACT: Lynn Lankshear, NMFS Greater Atlantic 
Regional Fisheries Office, Protected Resources Division, (978) 282-
8473, [email protected].

SUPPLEMENTARY INFORMATION:

Background

    A ``species'' is defined in section 3 of the ESA to include ``any 
subspecies of fish or wildlife or plants, and any distinct population 
segment of any species of vertebrate fish or wildlife which interbreeds 
when mature'' (16 U.S.C. 1532(16)). On July 19, 2023, we received a 
petition from the Delaware Riverkeeper Network (DRN) to list the 
Delaware River Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) 
population as a DPS, to list that DPS as endangered under the ESA, and 
to designate critical habitat for that DPS concurrent with the listing. 
The Delaware River Atlantic sturgeon population is currently protected 
under

[[Page 47090]]

the ESA as part of the New York Bight DPS of Atlantic sturgeon, and 137 
kilometers (85 miles) of the lower Delaware River are included as part 
of the designated critical habitat for the DPS.
    We listed the New York Bight DPS as endangered after two separate 
status reviews. The first status review, which was completed in 1998, 
was conducted by NMFS and the U.S. Fish and Wildlife Service 
(collectively the ``Services'') in response to a petition to list 
Atlantic sturgeon in the United States under the ESA. We concluded that 
listing Atlantic sturgeon as a subspecies \1\ was not warranted (63 FR 
50187, September 21, 1998). The second status review was completed in 
2007. It concluded that there was new information to support listing 
Atlantic sturgeon in the United States as five DPSs (Atlantic Sturgeon 
Status Review Team (ASSRT), 2007).
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    \1\ Our finding considered whether listing Atlantic sturgeon in 
its North American range, including Atlantic Canada, was warranted. 
63 FR 50187.
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    On October 6, 2009, NMFS received a petition to list Atlantic 
sturgeon throughout its range as endangered or, alternatively, to list 
the five DPSs described in the 2007 status review. We reviewed the 
available information, including the 2007 Atlantic sturgeon status 
review report, and determined, in accordance with the Services' joint 
DPS Policy (61 FR 4722, February 7, 1996), that the U.S. populations of 
Atlantic sturgeon comprised five DPSs because they met both criteria of 
the policy--i.e., that the populations are both ``discrete'' and 
``significant'' (77 FR 5880, February 6, 2012; 77 FR 5914, February 6, 
2012). Evidence to support the existence of discrete Atlantic sturgeon 
populations included temporal and spatial separation during spawning 
and the results from genetic analyses. The significance criterion was 
met because each identified DPS persists in an ecological setting that 
is unique relative to the taxon as a whole, and the loss of any of the 
five DPSs would result in a significant gap in the range of the taxon. 
After reviewing the best available information regarding each DPSs' 
current status and extinction risk, we listed four DPSs as endangered 
(including the New York Bight DPS) and one as threatened (77 FR 5880, 
February 6, 2012; 77 FR 5914, February 6, 2012).
    The New York Bight DPS is defined in the regulations as all 
Atlantic sturgeon spawned in the watersheds that drain into coastal 
waters from Chatham, Massachusetts, to the Delaware-Maryland border on 
Fenwick Island (50 CFR 224.101). The Delaware River and the Hudson 
River populations of Atlantic sturgeon were the only known extant 
populations for the DPS when it was listed. We subsequently identified 
the areas of the Delaware River and the Hudson River where the physical 
and biological features essential for successful reproduction and 
recruitment of the respective Atlantic sturgeon populations are found. 
We designated these areas as critical habitat for the New York Bight 
DPS on August 17, 2017 (82 FR 39160).
    We completed a 5-year review of the New York Bight DPS on February 
17, 2022. In that review, we described new information available since 
the listing, including information that further supports our 
understanding of when spawning occurs in the Delaware River, the 
genetic assignment of Delaware River Atlantic sturgeon to the New York 
Bight DPS and the river-of-origin, and where the Delaware River 
Atlantic sturgeon occur in the marine environment (NMFS, 2022). We also 
described new information suggesting a possible spawning population in 
the Connecticut River for which research is on-going. As summarized in 
the 5-year review, the information available since the listing 
continues to support our determination in the 2012 listing rule that 
the New York Bight DPS is both discrete and significant relative to the 
taxon as a whole. We found no new information that would change our 
determinations regarding the application of the DPS Policy, the status 
of the DPS, or its designated critical habitat (NMFS, 2022).

ESA Statutory, Regulatory, and Policy Provisions and Evaluation 
Framework

    Section 4(b)(3)(A) of the ESA of 1973, as amended (16 U.S.C. 1531 
et seq.), requires, to the maximum extent practicable, that within 90 
days of receipt of a petition to list a species as threatened or 
endangered, the Secretary of Commerce shall make a finding on whether 
that petition presents substantial scientific or commercial information 
indicating that the petitioned action may be warranted, and promptly 
publish such finding in the Federal Register (16 U.S.C. 1533(b)(3)(A)). 
If NMFS finds that substantial scientific or commercial information in 
a petition indicates the petitioned action may be warranted (a 
``positive 90-day finding''), we are required to promptly commence a 
review of the status of the species concerned, during which we will 
conduct a comprehensive review of the best available scientific and 
commercial data. In such cases, within 12 months of receipt of the 
petition, we conclude the review with a finding as to whether, in fact, 
the petitioned action is warranted. Because the finding at the 12-month 
stage is based on a more thorough review of the best available 
information, as compared to the narrow scope of review at the 90-day 
stage, a ``positive 90-day finding'' does not prejudge the outcome of 
the status review.
    Under the ESA, a listing determination may address a species, which 
is defined to also include subspecies and, for any vertebrate species, 
any DPS that interbreeds when mature (16 U.S.C. 1532(16)). The Services 
joint DPS Policy clarifies the agencies' interpretation of the phrase 
``distinct population segment'' for the purposes of listing, delisting, 
and reclassifying a species under the ESA (61 FR 4722, February 7, 
1996). A species, subspecies, or DPS is ``endangered'' if it is in 
danger of extinction throughout all or a significant portion of its 
range, and ``threatened'' if it is likely to become endangered within 
the foreseeable future throughout all or a significant portion of its 
range (ESA sections 3(6) and 3(20), respectively, 16 U.S.C. 1532(6) and 
(20)). Pursuant to the ESA and our implementing regulations, we 
determine whether species are threatened or endangered based on any one 
or a combination of the following section 4(a)(1) factors: (1) The 
present or threatened destruction, modification, or curtailment of 
habitat or range; (2) overutilization for commercial, recreational, 
scientific, or educational purposes; (3) disease or predation; (4) 
inadequacy of existing regulatory mechanisms to address identified 
threats; (5) or any other natural or manmade factors affecting the 
species' existence (16 U.S.C. 1533(a)(1), 50 CFR 424.11(c)).
    ESA-implementing regulations issued jointly by the Services (50 CFR 
424.14(h)(1)(i)) define ``substantial scientific or commercial 
information'' in the context of reviewing a petition to list, delist, 
or reclassify a species as credible scientific or commercial 
information in support of the petition's claims such that a reasonable 
person conducting an impartial scientific review would conclude that 
the action proposed in the petition may be warranted. Conclusions drawn 
in the petition without the support of credible scientific or 
commercial information will not be considered substantial information. 
In reaching the initial (90-day) finding on the petition, we consider 
the information described in sections 50 CFR 424.14(c), (d), and (g) 
(if applicable) and may also consider information readily available at 
the time the determination is made (50 CFR 424.19(h)(1)(ii)).

[[Page 47091]]

    Our determination as to whether the petition provides substantial 
scientific or commercial information indicating that the petitioned 
action may be warranted depends in part on the degree to which the 
petition includes the following types of information: (1) information 
on current population status and trends and estimates of current 
population sizes and distributions, both in captivity and the wild, if 
available; (2) identification of the factors under section 4(a)(1) of 
the ESA that may affect the species and where these factors are acting 
upon the species; (3) whether, and to what extent, any or all of the 
factors alone or in combination identified in section 4(a)(1) of the 
ESA may cause the species to be an endangered species or threatened 
species (i.e., the species is currently in danger of extinction or is 
likely to become so within the foreseeable future), and, if so, how 
high in magnitude and how imminent the threats to the species and its 
habitat are; (4) information on adequacy of regulatory protections and 
effectiveness of conservation activities by States, as well as other 
parties, that have been initiated or that are ongoing, that may protect 
the species or its habitat; and (5) a complete, balanced representation 
of the relevant facts, including information that may contradict claims 
in the petition. See 50 CFR 424.14(d).
    We may also consider information readily available at the time the 
determination is made (50 CFR 424.14(h)(1)(ii)). We are not required to 
consider any supporting materials cited by the petitioner if the 
petitioner does not provide electronic or hard copies, to the extent 
permitted by U.S. copyright law, or appropriate excerpts or quotations 
from those materials (e.g., publications, maps, reports, and letters 
from authorities). See 50 CFR 424.14(c)(6) and (h)(1)(ii).
    The ``substantial scientific or commercial information'' standard 
must be applied in light of any prior reviews or findings we have made 
on the listing status of the species that is the subject of the 
petition (50 CFR 424.14(h)(1)(iii)). Where we have already conducted a 
finding on, or review of, the listing status of that species (whether 
in response to a petition or on our own initiative), we will evaluate 
any petition received thereafter seeking to list, delist, or reclassify 
that species to determine whether a reasonable person conducting an 
impartial scientific review would conclude that the action proposed in 
the petition may be warranted despite the previous review or finding. 
Where the prior review resulted in a final agency action--such as a 
final listing determination, a 90-day not-substantial finding (i.e., 
negative 90-day finding), or a 12-month not-warranted finding--a 
petition will generally not be considered to present substantial 
scientific and commercial information indicating that the petitioned 
action may be warranted unless the petition provides new information or 
analysis not previously considered. See 50 CFR 424.14(h)(1)(iii).
    At the 90-day finding stage, we do not conduct additional research, 
and we do not solicit information from parties outside the agency to 
help us in evaluating the petition. We accept the petitioner's sources 
and characterizations of the information presented if they appear to be 
based on accepted scientific principles, unless we have specific 
information in our files that indicates the petition's information is 
incorrect, unreliable, obsolete, or otherwise irrelevant to the 
requested action. Information that is susceptible to more than one 
interpretation, or that is contradicted by other available information, 
will not be dismissed at the 90-day finding stage, so long as it is 
reliable and a reasonable person conducting an impartial scientific 
review could conclude it supports the petitioner's assertions. In other 
words, conclusive information indicating the species may meet the ESA's 
requirements for listing is not required to make a positive 90-day 
finding.
    To make a 90-day finding on a petition to list a species, we first 
evaluate whether the information presented in the petition, in light of 
the information readily available in our files, indicates that the 
petitioned entity constitutes a species eligible for listing under the 
ESA. Next, we evaluate whether the petition presents substantial 
scientific or commercial information indicating the subject species may 
be either a threatened or endangered species, as defined by the ESA. 
This may be indicated in information expressly discussing the species' 
status and trends, or in information describing impacts and threats to 
the species. We evaluate whether the petition presents any information 
on specific demographic factors pertinent to evaluating extinction risk 
for the species (e.g., population abundance and trends, productivity, 
spatial structure, age structure, sex ratio, diversity, current and 
historical range, habitat integrity, or fragmentation), and the 
potential contribution of identified demographic risks to extinction 
risk for the species. We then evaluate whether the petition presents 
information suggesting potential links between these demographic risks 
and the causative impacts and threats identified in section 4(a)(1) of 
the ESA.
    Information presented on impacts or threats should be specific to 
the species and should reasonably suggest that one or more of these 
factors may be operative threats that act, or have acted, on the 
species to the point that it may warrant protection under the ESA. 
Broad statements about generalized threats to the species, or 
identification of factors that could negatively impact a species, do 
not constitute substantial information indicating that listing may be 
warranted. We look for information indicating that not only is the 
particular species exposed to a factor, but that the species may be 
responding in a negative fashion. We then assess the potential 
significance of that negative response.
    Many petitions identify risk classifications made by 
nongovernmental organizations, such as the International Union for 
Conservation of Nature (IUCN), the American Fisheries Society, or 
NatureServe, as evidence of extinction risk for a species. Risk 
classifications by other organizations or made under other Federal or 
State statutes may be informative, but such classification alone may 
not provide the rationale for a positive 90-day finding under the ESA. 
For example, as explained by NatureServe, their assessments of a 
species' conservation status do not constitute a recommendation by 
NatureServe for listing under the ESA because NatureServe assessments 
have different criteria, evidence requirements, purposes, and taxonomic 
coverage than government lists of endangered and threatened species, 
and therefore these two types of lists should not be expected to 
coincide (https://explorer.natureserve.org/AboutTheData/DataTypes/ConservationStatusCategories). Additionally, species classifications 
under IUCN and the ESA are not equivalent; data standards, criteria 
used to evaluate species, and treatment of uncertainty are also not 
necessarily the same. Thus, when a petition cites such classifications, 
we will evaluate the source of information that the classification is 
based upon in light of the standards on extinction risk and impacts or 
threats in accordance with the ESA and our implementing regulations as 
discussed above.

Analysis of Petition

    The petitioner requests that we list the Delaware River population 
of Atlantic sturgeon as a separate DPS under the ESA, list that DPS as 
endangered, and designate critical habitat for the DPS. As noted above, 
the Delaware River population of Atlantic

[[Page 47092]]

sturgeon is currently afforded the protections of an endangered species 
because it is part of the ESA-listed, endangered New York Bight DPS of 
Atlantic sturgeon. The petitioner did not request any other changes to 
the New York Bight DPS that may be necessary if the Delaware population 
was listed as its own DPS (e.g., changes to the regulatory definition 
of the New York Bight DPS without the Delaware River population or 
changes to the status of the New York Bight DPS).
    As noted above, where we have already conducted a finding or review 
of the listing status of a species (whether in response to a petition 
or on our own initiative), we will evaluate any petition received 
thereafter seeking to list, delist, or reclassify that species to 
determine whether a reasonable person conducting an impartial 
scientific review would conclude that the action proposed in the 
petition may be warranted despite the previous review of finding. 
Therefore, despite our previous determination that the Delaware River 
population of Atlantic sturgeon is part of the New York Bight DPS, we 
evaluated whether this petition provides new information or a new 
analysis not previously considered to determine whether the petitioned 
action may be warranted.
    The petitioner asserts that there has been significant research 
following the 2007 status review (ASSRT, 2007) and the 2012 listing 
determinations for the Atlantic sturgeon DPSs, and that the 
information, scientific studies, and expert analyses are available in 
the ``relevant literature'' section provided at the end of the 
petition. The petitioner did not, however, cite to specific references 
for the assertions that they made in the petition. We reviewed the 
literature provided by the petitioner to identify whether that 
literature provides any relevant new information that became available 
after the listing of the New York Bight DPS under the ESA (77 FR 5880, 
February 6, 2012) and after we completed the literature review for the 
5-year review of the New York Bight DPS (NMFS, 2022), and to identify 
any other information that we had not previously considered.
    We found that we have already considered most of the literature 
that was provided by the petitioner, and we have cited it either in the 
2007 status review (ASSRT, 2007), the listing determinations (77 FR 
5880, February 6, 2012; 77 FR 5914, February 6, 2012), or in our recent 
5-year review for the New York Bight DPS (NMFS, 2022). The studies that 
focused on genetics related to the Delaware River population (e.g., 
King et al., 2001; Waldman et al., 1996a, 1996b, 1998, 2002; Wirgin et 
al., 2000) provided some of the earliest results that documented 
genetic differentiation among Atlantic sturgeon populations. These 
results were described and used by the ASSRT to inform the 2007 status 
review (ASSRT, 2007). Additional genetic analyses were conducted for 
the 2007 status review to inform whether there were discrete 
populations of Atlantic sturgeon (ASSRT, 2007). We considered all of 
this information as well as the results of Wirgin et al. (2007) and 
Grunwald et al. (2008), which became available after completion of the 
2007 status review, in reaching our listing determinations (77 FR 5880, 
February 6, 2012; 77 FR 5914, February 6, 2012). There was no new 
information regarding the differentiation of the Atlantic sturgeon 
populations, in general, or for the New York Bight DPS, specifically, 
when we completed the 5-year review for the DPS (NMFS, 2022). We did, 
however, review and describe new life history information for the New 
York Bight DPS (e.g., distribution in their marine range, occurrence in 
certain coastal estuaries) that became available as a result of studies 
that used genetic analysis to identify the origin of the individual 
sturgeon captured (NMFS, 2022). The genetic studies reviewed and cited 
for the 5-year review were Dunton et al. (2012), Kazyak et al. (2021), 
O'Leary et al. (2014), Waldman et al. (2013, 2019), and Wirgin et al. 
(2015a, 2015b); all of which the petitioner also lists in the 
``relevant literature.''
    Some of the sturgeon studies provided by the petitioner can be 
found in NMFS' files on Atlantic sturgeon but do not provide 
information relevant to considering whether the Delaware River 
population of Atlantic sturgeon may meet the discreteness and 
significance criteria of the Service's joint DPS Policy. These include 
Balazik et al. (2017), which described the James River populations of 
Atlantic sturgeon; Farrae et al. (2017), which described the Edisto 
River populations of Atlantic sturgeon; and Panagiotopoulou et al. 
(2014a and 2014b), which described methodology for analyzing genetic 
information of North American and European stocks of Atlantic sturgeon. 
We could not make any connection between these studies and the 
petitioner's statements that the Delaware River population of Atlantic 
sturgeon is discrete and warrants listing as its own, endangered DPS.
    We identified eight reports or publications in the ``relevant 
literature'' section at the end of the petition that became available 
after we completed our literature search for the 5-year review of the 
New York Bight DPS. Four of these references relate to Atlantic 
sturgeon genetics (i.e., White et al., 2021a, 2021b, 2022; Wirgin et 
al., 2023), and four relate to impacts to the Delaware River population 
of Atlantic sturgeon or its habitat (i.e., Delaware River Basin 
Commission (DRBC), 2022a, 2022b; Environmental Research and Consulting 
(ERC) and Verdantas, 2022; Hagy, 2023).
    Accordingly, we reviewed these eight references to determine 
whether they provide new information to show that the Delaware River 
population of Atlantic sturgeon may meet the criterion of the Service's 
joint DPS Policy (61 FR 4722, February 7, 1996). First, and as 
discussed below, we focused on the assertions made by the petitioner 
regarding discreetness, the first prong in the DPS analysis. We 
considered information in our files, and the four new references 
pertaining to genetics, to determine if the petition presents new 
information not previously considered with regard to whether the 
Delaware River population may be discrete. We also reviewed the 
information provided from the other four references (DRBC, 2022a, 
2022b; ERC and Verdantas, 2022; Hagy, 2023), but found they did not 
contain new information that informed whether the Delaware River 
population may be discrete.
    The petitioner claims that the Delaware River population of 
Atlantic sturgeon is discrete because it is genetically unique with 
characteristics found only in the Delaware River population. The 
petitioner's conclusion presents only part of the information available 
in the literature with regard to unique characteristics found in 
sturgeon populations. Some mitochondrial haplotypes and some 
microsatellite alleles are unique to some individuals of the Delaware 
River population. However, that does not mean that the population is 
discrete. The results of analyses conducted for the 2007 status review 
revealed that some mitochondrial DNA haplotypes were unique to specific 
Atlantic sturgeon river populations, such as the A5 haplotype for the 
Delaware River population (ASSRT, 2007). However, only a minority of 
the Delaware River sturgeon that were tested had the unique haplotype. 
The results of Wirgin et al. (2007) and Grunwald et al. (2008) provided 
additional information that the A5 haplotype is found in only a 
minority of the fish belonging to the Delaware River population. Wirgin 
et al. (2007) and Grunwald et al. (2008) also found that haplotypes B 
and B1 are found only in the Delaware River and the Hudson River 
populations. Overall, the results of studies that we reviewed and 
considered as part of the 5-year

[[Page 47093]]

review of the New York Bight DPS support the conclusion that: the 
Delaware River population as well as many of the other Atlantic 
sturgeon river populations have a unique haplotype; only a minority of 
the individual sturgeon sampled in each population carry the unique 
haplotype; the Hudson River and Delaware River populations of Atlantic 
sturgeon share unique haplotypes that are not found in any of the other 
Atlantic sturgeon populations; and the majority of individuals in each 
Atlantic sturgeon population carry haplotypes that are common to all or 
many of the sturgeon populations (Savoy et al., 2017; Waldman et al., 
2013; Wirgin et al., 2015b). Therefore, the unique A5 haplotype carried 
by some individuals in the Delaware River population does not support 
that the population is discrete.
    The four new studies cited by the petitioner in the ``relevant 
literature'' use microsatellite DNA rather than mitochondrial DNA. In 
the case of microsatellite DNA, similar to the available information on 
mitochondrial DNA haplotypes, private alleles (i.e., a version of a 
gene sequence that is found only in a single population) occur in 
Atlantic sturgeon populations and most Atlantic sturgeon populations 
have at least one private allele that is carried by at least one 
individual of that population. White et al. (2021a) found that the 
majority of the sturgeon groups tested contained at least one private 
allele across all loci. However, not all individuals of a population 
carry the unique allele. In addition, sampling bias can influence 
whether and where a private allele is discovered. For example, an 
allele may be detected by chance in one population and may be 
misidentified as a private allele because the same allele also occurs 
in other populations but has not yet been detected in samples from 
another population. The scientific literature for the genetics 
information available to us for the 2007 status review, the listing 
determinations, and the 5-year review of the New York Bight DPS all 
describe the methods used to analyze Atlantic sturgeon genetics data 
which include screening for multiple, specific, microsatellite loci, 
use of reference collections, and various analytical tools described in 
each scientific publication. The new genetic studies included in the 
petitioner's ``relevant literature'' also used these methods to further 
inform Atlantic sturgeon population structuring (White et al., 2021a), 
the origin of sturgeon captured in the New York Bight directed fishery 
in the 1990s (White et al., 2021b), the estimated spawning abundance 
for the Delaware River population (White et al., 2022), and population 
structuring (i.e., genetic differentiation between population segments) 
for the South Atlantic DPS (Wirgin et al., 2023). None of the studies 
relied on identification of individuals from the Delaware River 
population based solely on the presence of unique haplotypes or 
alleles, and none provided new information for the Delaware River 
population's marked separation from the other populations such that it 
may be considered discrete as contemplated in the Services' DPS Policy. 
The information available in White et al. (2021a, 2021b, 2022) and 
Wirgin et al. (2023) does not include new information on the genetic 
uniqueness of the Delaware River population of Atlantic sturgeon. In 
fact, all of these studies are consistent with the existing 
information, that only some individuals carry the unique A5 haplotype 
or unique allele, which we presented in our listing determination and 
5-year review for the New York Bight DPS. The information available in 
these new studies corroborates our listing determination that the 
Delaware River population of Atlantic sturgeon and the Hudson River 
population of Atlantic sturgeon are part of the same DPS.
    The petitioner asserted that the Delaware River population of 
Atlantic sturgeon is clearly recognizable from both mitochondrial and 
nuclear DNA markers such that individuals are correctly assigned to the 
Delaware River genetic group at very high rates, among the highest 
rates for any river population. The petitioner is correct that 
individuals are assigned to the Delaware River population at relatively 
high rates; however, as described above, individual Atlantic sturgeon 
are not assigned to the Delaware River population based on the A5 
haplotype or a private allele, as asserted by the petitioner, because 
those are only present in some individuals of the population. A much 
more rigorous methodology is used by the geneticists in the above-
referenced studies to assign individual Atlantic sturgeon to the river 
and DPS of origin and a number of factors can influence assignment 
certainty. Those factors include the quality of the extracted DNA from 
the sample (e.g., as a result of sample preservation) and the genetic 
baseline. The genetic baseline is a reference collection of samples 
from individual Atlantic sturgeon captured in a river and assumed to be 
natal to that river because the fish was captured either as a river 
resident juvenile (i.e., too physiologically immature to leave the 
natal estuary) or as an adult in spawning condition on the known or 
presumed spawning grounds of that river's spawning population. The 
methods used to establish the genetic baseline and the expansion of the 
baseline are described in the literature provided by the petitioner 
(ASSRT, 2007; Waldman et al., 2013; Wirgin et al., 2015b; Kazyak et 
al., 2021; White et al., 2021a). The Delaware River reference 
collection is based solely on samples from river resident juveniles 
(Kazyak et al., 2021), which makes for a very strong reference 
collection, and, in turn, imparts a high level of certainty when making 
individual assignments to the Delaware River population. White et al. 
(2021a) and Wirgin et al. (2023)--both new publications provided by the 
petitioner--include discussions of assignment certainty with respect to 
the southern DPSs and their reference collections that demonstrate the 
connection between the strength of the genetics baseline and assignment 
certainty. As noted in our listing determination (77 FR 5880, February 
6, 2012), assignment certainty reflects several factors, including 
sampling methods used and samples available to develop the genetics 
baseline, but assignment certainty is not a stand-alone factor for 
determining that a population is discrete.
    The petitioner also claims that fidelity to the natal spawning 
river is so high that the Delaware River population is reproductively 
isolated from all other river populations including the Hudson River 
population, and, effectively, zero cross-river migration occurs. It is 
unclear from the petitioner's statement whether they contend that the 
Delaware population is reproductively isolated such that only natal 
Delaware River fish spawn together, or whether, given the petitioner's 
use of the term ``effectively,'' the petitioner is stating that some 
low level of spawning occurs between the Delaware River population and 
the Hudson River population. As described in the listing determination, 
based on extensive research, including genetic analyses and tagging and 
tracking data, the vast majority of Atlantic sturgeon return to their 
natal rivers to spawn, with some studies showing only one or two 
individuals per generation spawning outside their natal river system 
(77 FR 5880, February 6, 2012). Our statements in the listing 
determination were based on the scientific research described in Wirgin 
et al. (2000), King et al. (2001), and Waldman et al. (2002); all of 
which are

[[Page 47094]]

also included by the petitioner in the ``relevant literature.'' The 
publications and reports available for the 5-year review of the New 
York Bight DPS did not change our conclusions regarding fidelity of the 
Delaware River or the Hudson River populations of Atlantic sturgeon to 
their natal river. Those publications and reports are also included in 
the petitioner's ``relevant literature.'' Of the four new genetic 
studies provided by the petitioner, White et al. (2021a) further 
investigates population structure by using an expanded baseline of more 
than 2,500 sampled Atlantic sturgeon and multiple analytical techniques 
to describe the coastwide population structure for Atlantic sturgeon. 
Their results further demonstrate that the Atlantic sturgeon 
populations exhibit high fidelity to their natal river at spawning.
    The three other genetic publications provided by the petitioner do 
not provide new information that is relevant to the petitioner's 
statement that the Delaware River population is reproductively isolated 
or to the overall discreteness of this population. White et al. (2021b) 
describes new information based on genetic analysis of Atlantic 
sturgeon fin spines to identify the origins of Atlantic sturgeon 
captured in the New York fishery in the 1990s. White et al. (2022) 
describes the feasibility of a new method for estimating the number of 
spawning adults for the Delaware River population of Atlantic sturgeon. 
It is based on the knowledge that there is high spawning fidelity for 
the Delaware River population, but the purpose of the research was not 
to investigate spawning fidelity and it does not provide any new 
information that would support the petitioner's statement. Wirgin et 
al. (2023), while noting that their results for population structuring 
of all but the South Atlantic DPS will be reported elsewhere, states 
that the certainty of genetic assignments was high for both Atlantic 
sturgeon belonging to the Delaware River population and for Atlantic 
sturgeon belonging to the Hudson River population, and that the 
assignment certainty was even higher at the DPS-level. Other studies 
(e.g., Kazyak et al., 2021) have also found a higher level of certainty 
for DPS-level assignments compared to the river specific assignments 
within the DPS, which suggests that there is some limited genetic 
exchange between river populations within a DPS.
    We described in the proposed listing rule why we proposed to list 
Atlantic sturgeon as five DPSs (75 FR 61872, October 6, 2010). In 
summary, we identified five discrete Atlantic sturgeon population 
segments based on the evidence that each discrete population is 
temporally and spatially separated during spawning. The results of 
genetic analyses further supported that there is strong fidelity to the 
natal river at spawning time. We concluded that the five discrete 
Atlantic sturgeon population segments meet the significance criterion 
of the DPS Policy because each reproduces in a unique ecological 
setting, and the loss of any of these discrete population segments 
would result in a significant gap in the range of the taxon. We 
responded to public comment, including comments from the petitioner 
(DRN Comment, November 9, 2010), to further explain why we were listing 
the Delaware River and the Hudson River populations of Atlantic 
sturgeon as a single DPS (see Response to Comments 13 and 16; 77 FR 
5890 and 5892, February 6, 2012). In their comments, as in this 
petition, the petitioner claimed that the Delaware River population of 
Atlantic sturgeon is genetically unique as evidenced by the presence of 
the A5 haplotype, and that including the Delaware River population and 
the Hudson River population into a single DPS affords less ESA 
protection to the Delaware River population. We acknowledged in our 
responses to their comments that genetics could be used to distinguish 
Atlantic sturgeon that originate from the Delaware River population 
from those that originate from the Hudson River population. However, we 
also stated that even though the Delaware River population was 
genetically distinguishable from the Hudson River population, based 
upon our evaluation of whether Atlantic sturgeon population segments 
met the DPS Policy criteria, we could delineate five Atlantic sturgeon 
DPSs (as described in detail in the proposed rule). Based on 
application of the DPS Policy criteria, we determined that the Delaware 
River population did not meet the criteria of a DPS on its own because 
its spawning time was not temporally separated from that of the Hudson 
River population, the spawning habitat of both the Delaware River and 
the Hudson River populations occur within the same unique ecological 
setting, and analyses of the genetic data for population structuring 
indicated that the two rivers grouped together (see 75 FR 61876, 
October 6, 2010). We considered our decision during the 5-year review 
of the New York Bight DPS in light of new information that had become 
available since the listing, and we concluded that no changes to the 
listing of the New York Bight DPS were warranted. We have reviewed and 
considered the four new genetic studies provided by the petitioner and 
listed in their ``relevant literature.'' As described above, none of 
these provide new information regarding the discreteness of the 
Delaware River population of Atlantic sturgeon. On the contrary, one 
new study, White et al. (2021a), provides additional information that 
corroborates our listing determination for the New York Bight DPS. As 
described above, the three other genetic publications provided by the 
petitioner do not provide new information that is relevant to the 
petitioner's assertion that the Delaware River population is 
reproductively isolated or to the overall discreteness of this 
population.
    A DPS must be both discrete and significant to the taxon as a 
whole. If a population is found to be discrete in accordance with the 
Service's joint DPS Policy, we next consider whether that discrete 
population is also significant in the context of the joint DPS Policy. 
In this case, the petitioner has not provided new information to show 
that the Delaware River population of Atlantic sturgeon may be 
discrete. We also note that the petitioner appears to be confusing the 
meaning of the term ``significance'' in the context of the joint DPS 
Policy with the word ``significance'' as it is used in everyday 
language. The joint DPS Policy directs the Services to consider 
available scientific evidence of the discrete population segment's 
importance to the taxon to which it belongs (61 FR 4722, February 7, 
1996). However, the petitioner's ``relevant literature'' provides no 
scientific evidence that speaks to the significance of the Delaware 
River population of Atlantic sturgeon to the taxon as a whole. Instead, 
the petitioner claims that the Delaware population of Atlantic sturgeon 
is significant because of the population's historical abundance. This 
reference to the historical abundance of the Delaware River population 
does not provide any new information. In the proposed and final listing 
rules we described the significant range-wide declines in Atlantic 
sturgeon from historical abundance levels due to overfishing, and we 
stated that the best available data indicated that current numbers of 
spawning adults for each DPS are one to two orders of magnitude smaller 
than historical levels. We also described the Delaware River population 
as presumably very small and extremely vulnerable to any sources of 
anthropogenic mortality. In addition, the petitioner claims that the 
Delaware River population of Atlantic sturgeon

[[Page 47095]]

has ``unique adaptive characteristics that will help the species adapt 
to a changing environment.'' However, we could not find any information 
in the ``relevant literature'' that supported this statement nor any 
such information in our files.
    We also do not consider here the petitioner's request to list a 
Delaware River DPS as endangered and to designate critical habitat for 
the DPS since both of these are dependent on a determination that the 
Delaware River population may warrant listing as a DPS. However, as 
described above, the ``relevant literature'' includes four new reports 
relative to impacts to the Delaware River population of Atlantic 
sturgeon or its habitat (i.e., DRBC, 2022a, 2022b; ERC and Verdantas, 
2022; Hagy, 2023), and each report speaks to an impact that we 
previously identified for the Delaware River population (i.e., vessel 
strikes of the fish and low dissolved oxygen levels within its 
habitat). The petitioner did not include other information as required 
at 50 CFR 424.14(d). The petitioner did not include in the ``relevant 
literature'' section any new reports or publications relative to a need 
for a new critical habitat designation for the Delaware River 
population. Those reports or publications that were included (e.g., 
Allen et al., 2014; Breece et al., 2013; Brundage et al., 2009; 
Campbell and Goodman, 2004; and Lazzari et al., 1986) were also 
considered and used by us when we designated critical habitat in the 
Delaware River for the New York Bight DPS (82 FR 39160, February 17, 
2017; NMFS, 2017).

Petition Finding

    We thoroughly reviewed the petition, the list of references 
provided by the petitioner, and other literature and information 
readily available to us, and find that the petition does not provide 
any new information regarding the discreteness of the Delaware River 
population of Atlantic sturgeon or otherwise offer substantial 
information not already considered in our status review report (ASSRT, 
2007), the listing decision (77 FR 5880, February 6, 2012), or our 5-
year review (NMFS, 2022). As such, we find that the petition does not 
present substantial scientific or commercial information indicating 
that the petitioned action to identify the Delaware River population of 
Atlantic sturgeon as a DPS may be warranted. We note that the 
population will continue to be listed as endangered as part of the New 
York Bight DPS of Atlantic sturgeon and that critical habitat in the 
Delaware River will continue to be designated as part of the critical 
habitat for the New York Bight DPS.

References Cited

    A complete list of all references cited herein is available upon 
request (see FOR FURTHER INFORMATION CONTACT section).

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

    Dated: May 23, 2024.
Samuel D. Rauch, III,
Deputy Assistant Administrator for Regulatory Programs National Marine 
Fisheries Service.
[FR Doc. 2024-11767 Filed 5-30-24; 8:45 am]
BILLING CODE 3510-22-P