[Federal Register Volume 75, Number 193 (Wednesday, October 6, 2010)]
[Proposed Rules]
[Pages 61872-61904]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-24459]
[[Page 61871]]
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Part II
Department of Commerce
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National Oceanic and Atmospheric Administration
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50 CFR Parts 223 and 224
Endangered and Threatened Wildlife and Plants; Proposed Rules
Federal Register / Vol. 75, No. 193 / Wednesday, October 6, 2010 /
Proposed Rules
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
50 CFR Parts 223 and Part 224
RIN 0648-XJ00
[Docket No. 100903414-0414-02]
Endangered and Threatened Wildlife and Plants; Proposed Listing
Determinations for Three Distinct Population Segments of Atlantic
Sturgeon in the Northeast Region
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Proposed rule; request for comments.
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SUMMARY: We, NMFS, have completed an Endangered Species Act (ESA)
status review for Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus).
Based on the status review report (ASSRT, 2007), and other information
available since completion of the status review report, we have
determined that the species is comprised of five distinct population
segments (DPSs) that qualify as species under the ESA: Gulf of Maine
(GOM); New York Bight (NYB); Chesapeake Bay (CB); Carolina; and South
Atlantic. We have also determined that, for those DPSs that are located
within the jurisdiction of NMFS' Northeast Region, listing as
threatened is warranted for the GOM DPS, and listing as endangered is
warranted for the NYB DPS and CB DPS. A separate proposed listing
determination is issued for the two DPSs within NMFS' Southeast Region
in today's Federal Register.
DATES: Comments on this proposal must be received by January 4, 2011.
At least one public hearing will be held in a central location for each
DPS; notice of the locations and times of the hearings will be
published in the Federal Register not less than 15 days before the
hearings are held.
ADDRESSES: You may submit comments, identified by the RIN 0648-XJ00, by
any of the following methods:
Federal eRulemaking Portal: http//www.regulations.gov.
Follow the instructions for submitting comments.
Fax: To the attention of Lynn Lankshear at (978) 281-9394.
Mail or hand-delivery: Submit written comments to the
Assistant Regional Administrator, Protected Resources Division, NMFS,
Northeast Region, 55 Great Republic Drive, Gloucester, MA 01930.
Instructions:
All comments received are a part of the public record and will
generally be posted to http://www.regulations.gov without change. All
Personal Identifying Information (for example, name, address, etc.)
voluntarily submitted by the commenter may be publicly accessible. Do
not submit Confidential Business Information or otherwise sensitive or
protected information.
We will accept anonymous comments (enter ``n/a'' in the required
fields if you wish to remain anonymous). Attachments to electronic
comments will be accepted in Microsoft Word, Excel, WordPerfect, or
Adobe PDF file formats only.
The proposed rule, status review report, and other reference
materials regarding this determination are available electronically at
the following Web site at http://www.nero.noaa.gov/prot_res/CandidateSpeciesProgram/cs.htm or by submitting a request to the
Assistant Regional Administrator, Protected Resources Division, NMFS,
Northeast Region, 55 Great Republic Drive, Gloucester, MA 01930.
FOR FURTHER INFORMATION CONTACT: Lynn Lankshear, NMFS, Northeast Region
(978) 282-8473; Kimberly Damon-Randall, NMFS, Northeast Region (978)
282-8485; or Marta Nammack, NMFS, Office of Protected Resources (301)
713-1401.
SUPPLEMENTARY INFORMATION:
Public Comments Solicited
We solicit scientific and commercial information to inform the
listing determinations for the GOM, NYB, and CB DPSs to ensure that the
final action resulting from this proposal considers information that is
comprehensive and current. We particularly seek comments concerning:
information on the abundance and distribution of Atlantic sturgeon
belonging to the GOM, NYB, and/or the CB DPSs; information concerning
the viability of and/or threats to Atlantic sturgeon belonging to the
GOM, NYB, and/or the CB DPSs; efforts being made to protect Atlantic
sturgeon belonging to the GOM, NYB, or CB DPSs; and the mixing of fish
from different DPSs in parts of their ranges, particularly the marine
environment.
We are not proposing critical habitat for the GOM, NYB, or CB DPSs
at this time, given that further analysis of GIS mapping data is
necessary for determining the critical habitat of each of the three
DPSs. Therefore, we will propose to designate critical habitat for each
DPS in a separate Federal Register notification once analysis of the
data is complete. If the proposed listing is finalized, a recovery plan
will be prepared for each DPS. In addition, any protective regulations
determined to be necessary and advisable for the conservation of the
GOM DPS under ESA section 4(d) will be proposed in a subsequent Federal
Register document.
Background
There are two subspecies of Atlantic sturgeon--Acipenser oxyrinchus
oxyrinchus, which is commonly referred to as Atlantic sturgeon, and
Acipenser oxyrinchus desotoi, commonly referred to as Gulf sturgeon.
This proposed rule addresses the subspecies Acipenser oxyrinchus
oxyrinchus (hereafter referred to as Atlantic sturgeon), which is
distributed along the eastern coast of North America.
Listing Species Under the Endangered Species Act
We, NMFS, are responsible for determining whether Atlantic sturgeon
are threatened or endangered under the ESA (16 U.S.C. 1531 et seq.).
Accordingly, based on the statutory, regulatory, and policy provisions
described below, the steps we followed in making our listing
determination for Atlantic sturgeon were to: (1) Determine how Atlantic
sturgeon meet the definition of ``species''; (2) determine the status
of the species and the factors affecting it; and (3) identify and
assess efforts being made to protect the species and determine if these
efforts are adequate to mitigate existing threats.
To be considered for listing under the ESA, a group of organisms
must constitute a ``species.'' 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.'' On February 7, 1996, the NMFS
and U.S. Fish and Wildlife Service (collectively the ``Services'')
adopted a policy to clarify our interpretation of the phrase ``distinct
population segment of any species of vertebrate fish or wildlife'' (61
FR 4722). The joint DPS policy describes two criteria that must be
considered when identifying DPSs: (1) The discreteness of the
population segment in relation to the remainder of the species (or
subspecies) to which it belongs; and (2) the significance of the
population segment to the remainder of the species (or subspecies) to
which it belongs. As further stated in the joint policy, if a
population segment is discrete and significant (i.e., it meets the DPS
policy criteria), its evaluation for endangered or threatened status
will be based on the ESA's definition of those terms and a
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review of the five factors enumerated in section 4(a)(1) of the ESA.
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.'' As provided in section 4(a) of the
ESA, the statute requires us to determine whether any species is
endangered or threatened because of any of the following five factors:
(1) The present or threatened destruction, modification, or curtailment
of its habitat or range; (2) overutilization for commercial,
recreational, scientific, or educational purposes; (3) disease or
predation; (4) the inadequacy of existing regulatory mechanisms; or (5)
other natural or manmade factors affecting its continued existence
(section 4(a)(1)(A)(E)).
Section 4(b)(1)(A) of the ESA further requires that listing
determinations be based solely on the best scientific and commercial
data available after taking into account efforts being made to protect
the species. In judging the efficacy of existing protective efforts, we
rely on the Service's joint ``Policy for Evaluation of Conservation
Efforts When Making Listing Decisions'' (``PECE''; 68 FR 15100; March
28, 2003). The PECE provides direction for consideration of
conservation efforts that have not been implemented, or have been
implemented but not yet demonstrated effectiveness.
Status Review
We first identified Atlantic sturgeon as a candidate species in
1991; at that time, the candidate species list served to notify the
public that we had concerns regarding these species that may warrant
listing in the future, and it facilitated voluntary conservation
efforts. On June 2, 1997, the Services received a petition from the
Biodiversity Legal Foundation requesting that we list Atlantic sturgeon
in the United States as threatened or endangered and designate critical
habitat within a reasonable period of time following the listing. A
notice was published in the Federal Register on October 17, 1997,
stating that the Services had determined substantial information
existed indicating the petitioned action may be warranted (62 FR
54018). In 1998, after completing a comprehensive status review, the
Services published a 12-month determination in the Federal Register,
announcing that listing was not warranted at that time (63 FR 50187;
September 21, 1998). We retained Atlantic sturgeon on the candidate
species list (subsequently changed to the Species of Concern List (69
FR 19975; April 15, 2004)).
Concurrently, the Atlantic States Marine Fisheries Commission
(ASMFC) completed Amendment 1 to the 1990 Atlantic Sturgeon Fishery
Management Plan (FMP) that imposed a 20-40 year moratorium on all
Atlantic sturgeon fisheries until the Atlantic Coast spawning stocks
could be restored to a level where 20 subsequent year classes of adult
females were protected (ASMFC, 1998). In 1999, pursuant to section
804(b) of the Atlantic Coastal Fisheries Cooperative Management Act
(ACFCMA) (16 U.S.C. 5101 et seq.), we followed this action by closing
the Exclusive Economic Zone (EEZ) to Atlantic sturgeon retention. In
2003, we sponsored a workshop with the U.S. Fish and Wildlife Service
(FWS) and the ASMFC entitled ``Status and Management of Atlantic
Sturgeon,'' to discuss the status of Atlantic sturgeon along the
Atlantic Coast and determine what obstacles, if any, were impeding
their recovery (Kahnle et al., 2005). The results of the workshop
indicated some river populations (hereafter referred to as
``subpopulations'') seemed to be recovering while others were
declining. Bycatch and habitat degradation were noted as possible
causes for continued declines.
Based on the information gathered from the 2003 workshop on
Atlantic sturgeon, we decided that a second review of Atlantic sturgeon
status was needed to determine if listing as endangered or threatened
under the ESA was warranted. We, therefore, established a status review
team (SRT) consisting of NMFS, FWS, and U.S. Geological Survey (USGS)
scientists with relevant expertise to assist us in assessing the
viability of the species throughout all or a significant portion of its
range. The SRT was asked to consider the best scientific and commercial
information available, including the technical information and comments
from state and regional experts. The draft status review report
prepared by the SRT was peer reviewed by experts from academia, and
their comments were incorporated. A Notice of Availability of this
report was published in the Federal Register on April 3, 2007 (72 FR
15865).
On October 6, 2009, we received a petition from the Natural
Resources Defense Council to list Atlantic sturgeon as endangered under
the ESA. As an alternative, the petitioner requested that the species
be delineated and listed as the five DPSs described in the 2007
Atlantic sturgeon status review (ASSRT, 2007) (i.e., Gulf of Maine, New
York Bight, Chesapeake Bay, Carolina, and South Atlantic DPSs), with
the Gulf of Maine and South Atlantic DPSs listed as threatened, and the
remaining three DPSs listed as endangered. The petitioner also
requested that critical habitat be designated for Atlantic sturgeon
under the ESA. We published a Notice of 90-Day Finding on January 6,
2010 (75 FR 838), stating that the petition presented substantial
scientific or commercial information indicating that the petitioned
actions may be warranted.
The status review report upon which this proposed rule is based
provides extensive information on Atlantic sturgeon biology, life
history, distribution, and abundance to support its conclusions. A
summary of this information is provided below. More detailed
information is available in the status review report.
Biology and Life History of Atlantic Sturgeon
Atlantic sturgeon are distinguished by armor-like plates and a long
snout with a ventrally located protruding mouth. Four barbels crossing
in front of the mouth help the sturgeon to locate prey. Sturgeon are
omnivorous benthic feeders (feed off the bottom) and filter quantities
of mud along with their food. Adult sturgeon diets include mollusks,
gastropods, amphipods, isopods, and fish. Juvenile sturgeon feed on
aquatic insects and other invertebrates (ASSRT, 2007).
The general life history pattern of Atlantic sturgeon is that of a
long lived (approximately 60 years; Mangin, 1964; Stevenson and Secor,
1999), late maturing, estuarine dependent, anadromous species (ASSRT,
2007). They can reach lengths up to 14 feet (4.26 m), and weigh over
800 pounds (~364 kg).
Fecundity of female Atlantic sturgeon has been correlated with age
and body size, with observed egg production ranging from 400,000 to 4
million eggs per spawning year (Smith et al., 1982; Van Eenennaam et
al., 1996; Van Eenennaam and Doroshov, 1998; Dadswell, 2006). Female
gonad weight varies from 12-25 percent of the total body weight (Smith,
1907; Huff, 1975; Dadswell, 2006). Therefore, the fecundity of a 770-
pound (350 kg) female, like the one captured in the St. John River,
Canada, in 1924, could be 7-8 million eggs (Dadswell, 2006). The
average age at which 50 percent of the maximum lifetime egg production
is achieved is estimated to be 29 years (Boreman, 1997).
Atlantic sturgeon likely do not spawn every year. Multiple studies
have shown
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that spawning intervals range from 1-5 years for males (Smith, 1985;
Collins et al., 2000; Caron et al., 2002) and 2-5 years for females
(Vladykov and Greeley, 1963; Van Eenennaam et al., 1996; Stevenson and
Secor, 1999). Spawning behavior also differs between the sexes. While
there is a window of time for each river during which spawning occurs,
spawning females do not migrate upstream together. Individual females
make rapid spawning migrations upstream and quickly depart following
spawning (Bain, 1997). Spawning males usually arrive on the spawning
grounds before any of the females have arrived and leave after the last
female has spawned (Bain, 1997). Presumably, this provides an
opportunity for a single male to fertilize eggs of multiple females.
Spawning is believed to occur in flowing water between the salt
front of estuaries and the fall line of large rivers, where optimal
flows are 46-76 cm/s and depths are 11-27 m (Borodin, 1925; Leland,
1968; Scott and Crossman, 1973; Crance, 1987; Bain et al., 2000).
Sturgeon eggs are highly adhesive and are deposited on the bottom
substrate, usually on hard surfaces such as cobble (Gilbert, 1989;
Smith and Clugston, 1997). Hatching occurs approximately 94 and 140
hours after egg deposition at temperatures of 20[deg] and 18 [deg]C,
respectively, and, once hatched, larvae assume a demersal existence
(Smith et al., 1980). The yolksac larval stage is completed in about 8-
12 days, during which time the larvae move downstream to the rearing
grounds (Kynard and Horgan, 2002). During the first half of this
migration, larvae move only at night and use benthic structure (e.g.,
gravel matrix) as refuge during the day (Kynard and Horgan, 2002).
During the latter half of migration to the rearing grounds, when larvae
are more fully developed, movement occurs during both day and night.
Larvae transition into the juvenile phase as they continue to move even
further downstream into brackish waters, developing a tolerance to
salinity as they go, and eventually become residents in estuarine
waters for months to years before emigrating to open ocean as subadults
(Holland and Yelverton, 1973; Doevel and Berggen, 1983; Waldman et al.,
1996a; Dadswell, 2006; ASSRT, 2007).
Atlantic sturgeon that originate from different rivers demonstrate
differences in growth rate, maturation, and timing of spawning. For
example, Atlantic sturgeon mature in South Carolina river systems at 5
to 19 years (Smith et al., 1982), in the Hudson River at 11 to 21 years
(Young et al., 1998), and in the Saint Lawrence River at 22 to 34 years
(Scott and Crossman, 1973). In general, Atlantic sturgeon
subpopulations show clinal variation with faster growth and earlier age
at maturation for fish originating from more southern systems, though
not all data sets conform to this trend. Timing of spawning migrations
also exhibit a latitudinal pattern in which migrations generally occur
during February-March in southern systems, April-May in mid-Atlantic
systems, and May-July in Canadian systems (Murawski and Pacheco, 1977;
Smith, 1985; Bain, 1997; Smith and Clugston, 1997; Caron et al., 2002).
In some rivers, predominantly in the south, a fall spawning migration
may also occur (Rogers and Weber, 1995; Weber and Jennings, 1996; Moser
et al., 1998).
Distribution and Abundance
Historically, Atlantic sturgeon were present in approximately 38
rivers in the United States from St. Croix, ME, to the Saint Johns
River, FL, 35 of which have been confirmed to have supported spawning
for Atlantic sturgeon (ASSRT, 2007). It is unknown how many Canadian
rivers were historically used by Atlantic sturgeon. However, it is
likely that Atlantic sturgeon spawn(ed) in the Miramichi, Shubenacadie,
Avon, Annapolis, and in other systems of similar size in addition to
the presently known subpopulations that spawn in the Saint Lawrence
River and Saint John River (reviewed in Dadswell, 2006; ASSRT, 2007).
Overall, historical sightings of Atlantic sturgeon were generally
reported from Hamilton Inlet, Labrador, south to the Saint Johns River,
Florida (Murawski and Pacheko, 1977; Smith and Clugston, 1997; ASSRT,
2007). Occurrences south of the Saint Johns River, Florida, and north
of Hamilton Inlet, Labrador, may have always been rare.
It is clear that Atlantic sturgeon underwent significant range-wide
declines from historical abundance levels due to overfishing (reviewed
in Smith and Clugston, 1997). Although Atlantic sturgeon had been
previously exploited in commercial fisheries (Scott and Crossman, 1973;
Taub, 1990; Dadswell, 2006; ASSRT, 2007), records from the 1700s and
1800s document large numbers of sturgeon in many rivers along the
Atlantic coast (Kennebec River Resource Management Plan, 1993;
Armstrong and Hightower, 2002). However, in 1870, a significant fishery
for the species developed when a caviar market was established. Record
landings were reported in 1890, when over 3,350 metric tons (mt) of
Atlantic sturgeon were landed from coastal rivers along the Atlantic
Coast (reviewed in Smith and Clugston, 1997; Secor and Waldman, 1999).
The fishery collapsed in 1901, 10 years after peak landings, when less
than 10 percent (295 mt) of its 1890 peak landings were reported.
During the 1950s, the remaining fishery switched to targeting sturgeon
for flesh, rather than caviar. Commercial fisheries were active in many
rivers during all or some of the period from 1962 to 1997, albeit at
much lower levels than in the late 1800s--early 1900s (Taub, 1990;
Smith and Clugston, 1997). Nevertheless, many of these contemporary
fisheries also resulted in overfishing, which prompted the ASMFC to
impose the 1998 coastwide moratorium for fisheries targeting Atlantic
sturgeon and NMFS to close the EEZ to Atlantic sturgeon retention in
1999.
Currently, Atlantic sturgeon presence is documented in 36 rivers in
the United States and Canada, combined (ASSRT, 2007; J. Sulikowski,
UNE, pers. comm.). At least 18 rivers are believed to support spawning
based on available evidence (i.e., presence of young-of-year or gravid
Atlantic sturgeon documented within the past 15 years) (ASSRT, 2007).
These rivers are: Saint Lawrence, QB; Annapolis, NS; Saint John, NB;
Kennebec, ME; Hudson, NY; Delaware, NJ/DE/PA; James, VA; Roanoke, NC;
Tar-Pamlico, NC; Cape Fear, NC; Waccamaw, SC; Great PeeDee, SC;
Combahee, SC; Edisto, SC; Savannah, SC/GA; Ogeechee, GA; Altamaha, GA;
and, the Satilla, GA (ASSRT, 2007). Rivers with possible, but
unconfirmed, spawning include: St Croix, NB/ME; Penobscot,
Androscoggin, and Sheepscot, ME, York, VA; Neuse, NC; Santee and Cooper
Rivers; spawning may occur in the Santee and/or the Cooper Rivers, but
it may not result in successful recruitment (ASSRT, 2007).
Comprehensive information on current abundance of Atlantic sturgeon
is lacking for any of the spawning rivers (ASSRT, 2007). In the United
States, an estimate of 870 spawning adults/year is available for the
Hudson River (Kahnle et al., 2007). An estimate of 343 spawning adults/
year is available for the Altamaha River, GA, based on data collected
in 2004-2005 (Schueller and Peterson, 2006). Data collected from the
Hudson River and Altamaha River studies cannot be used to estimate the
total number of adults in either subpopulation, since mature Atlantic
sturgeon may not spawn every year (Vladykov and Greeley, 1963; Smith,
1985; Van Eenennaam et al., 1996; Stevenson and Secor, 1999; Collins et
al. 2000; Caron et al., 2002), and it is unclear to what extent mature
fish in a non-spawning condition occur on the
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spawning grounds. Nevertheless, since the Hudson and Altamaha rivers
are presumed to have the healthiest Atlantic sturgeon subpopulations
within the United States, other U.S. subpopulations are predicted to
have fewer spawning adults than either the Hudson or the Altamaha
(ASSRT, 2007). In Canada, an estimate of spawning size is available for
the Saint Lawrence River where tagging work suggests a total spawning
subpopulation of over 500 adults (Caron et al., 2002; Dadswell, 2006).
Surveys and other programs (e.g., reward programs) have provided
more qualitative information on Atlantic sturgeon subpopulations. While
these programs may not have sufficient information by which to generate
any subpopulation estimate(s), they do provide some river-specific
information on abundance, trends, evidence of spawning, and/or
documentation of multiple-year classes. For example, a multi-filament
gill net survey conducted intermittently in the Kennebec River from
1977-2000 captured 336 Atlantic sturgeon (9 adults and 327 subadults)
(Squiers, 2004). During this period, the catch-per-unit effort (CPUE)
of subadult Atlantic sturgeon increased by a factor of 10-25 (1977-1981
CPUE = 0.30 versus 1998-2000 CPUE = 7.43). The CPUE of adult Atlantic
sturgeon showed a slight increase over the same time period (1977-1981
CPUE = 0.12 versus 1998-2000 CPUE = 0.21) (Squiers, 2004).
An intensive gill net survey was conducted in the Merrimack River
from 1987-1990 to determine annual movements, spawning, summering, and
wintering areas of shortnose and Atlantic sturgeon (Kieffer and Kynard,
1993). Thirty-six Atlantic sturgeon were captured (70-156 cm total
length (TL)); most were under 100 cm TL, suggesting that these were all
subadult sturgeon (Kieffer and Kynard, 1993).
In Delaware, gill net surveys are conducted on the Delaware River
by the state's Division of Fish and Wildlife as part of their Atlantic
Sturgeon Research program. Since 1991, more than 2,000 Atlantic
sturgeon have been captured and tagged (DNREC, 2009). Based on their
length, most are believed to have been subadults. In September 2009,
however, personnel captured their smallest sturgeon yet; an age 0 fish,
which was 7 inches TL (178 mm) and weighed less than an ounce (DNREC,
2009). In all, 34 young-of-year (YOY) sturgeon were caught during the
sampling period (September 9-November 9, 2009), ranging in size from
178 to 349 mm TL (Fisher, 2009). These captures provide evidence that
successful spawning is still occurring in the Delaware River.
Within the Chesapeake Bay, the FWS has been funding the Maryland
Reward Program since 1996; this program has resulted in the
documentation of approximately 1,700 Atlantic sturgeon. Five hundred
and sixty-seven of these fish were hatchery fish, of which 462 were
first time captures (14 percent recapture rate), and the remaining
captures (1,133) were wild fish.
Virginia also instituted an Atlantic sturgeon reward program in the
Chesapeake Bay in 1997 and 1998 (ASSRT, 2007; A. Spells, FWS, pers.
comm., 2008). This reward program documented and measured 295 Atlantic
sturgeon. Data collected during the reward program documents the
presence of YOY fish. Such data include length information which shows
that 18.6 percent (55 of 295 measured) of the fish caught were within
the 20 to 40 cm fork length size class (A. Spells, FWS, pers. comm.,
2008). In addition, aging of fish spines collected from the fish
suggested that 34 percent were age 1 (A. Spells, FWS, pers. comm.,
2008). This information is important in that it strongly suggests the
presence of spawning in one or more rivers that flow into the Bay.
Further evidence of Atlantic sturgeon spawning in the Chesapeake Bay
area is provided by three carcasses of large adults found in the James
River in 2000-2003; the discovery of a 213 cm TL carcass of an adult
found in the Appomattox River in 2005; the capture and release of a 240
cm TL Atlantic sturgeon near Hoopers Island, MD in April, 1998 (S.
Minkkinen, FWS, pers. comm., 2006); documentation of a gravid adult
female Atlantic sturgeon off Tilghman Island, MD in April, 2007 (the
first gravid female documented in the Maryland portion of the
Chesapeake Bay since the early 1970s); and the capture of several males
producing milt (sperm) in the James River in 2007 and 2008 (A. Spells,
FWS, pers. comm.).
Identification of Distinct Population Segments
As described above, the ESA's definition of ``species'' includes
``any subspecies of fish or wildlife or plants, and any distinct
population segment of any species or vertebrate fish or wildlife which
interbreeds when mature.'' As previously described, Atlantic sturgeon
originating from different rivers are known to co-occur in the marine
environment and use multiple river systems for life functions, such as
foraging. The DPS policy does not require absolute separation of a DPS
from other members of its species (61 FR 4722; February 7, 1996). The
high degree of reproductive isolation of Atlantic sturgeon (i.e.,
homing to their natal rivers for spawning) (K. Hattala,, NYDEC, pers.
comm., 1998; Wirgin et al., 2000; King et al., 2001; Waldman et al.,
2002) as well as the ecological uniqueness of those riverine spawning
habitats and the genetic diversity among subpopulations, provides
evidence that several populations meet the DPS Policy criteria.
Therefore, prior to evaluating the conservation status for Atlantic
sturgeon, and in accordance with the joint DPS policy, we considered:
(1) The discreteness of any Atlantic sturgeon population segment in
relation to the remainder of the subspecies to which it belongs; and
(2) the significance of any Atlantic sturgeon population segment to the
remainder of the subspecies to which it belongs.
Discreteness
The joint DPS policy states that a population of a vertebrate
species may be considered discrete if it satisfies either one of the
following conditions: (1) It is markedly separated from other
populations of the same taxon as a consequence of physical,
physiological, ecological, or behavioral factors (quantitative measures
of genetic or morphological discontinuity may provide evidence of this
separation); or (2) it is delimited by international governmental
boundaries within which differences in control of exploitation,
management of habitat, conservation status, or regulatory mechanisms
exist that are significant in light of Section 4(a)(1)(D) of the ESA.
As has already been discussed, adult and subadult Atlantic sturgeon
which originate from different rivers mix in the marine environment
(Stein et al., 2004; USFWS, 2004). Nevertheless, there is marked
separation of Atlantic sturgeon as a result of both spatial and
temporal separation of reproduction among river subpopulations. Tagging
studies and genetic analyses provide evidence that Atlantic sturgeon
return to their natal rivers for spawning (K. Hattala, NYDEC, pers.
comm., 1998; Wirgin et al., 2000; King et al., 2001; Waldman et al.,
2002). As previously mentioned, Atlantic sturgeon are temporally
separated with respect to spawning, since all adults are not
reproductively active at the same time within each year (Murawski and
Pacheco, 1977; Smith, 1985; Rogers and Weber, 1995; Bain, 1997; Smith
and Clugston, 1997; Moser et al., 1998; Caron et al., 2002). For
example, Atlantic sturgeon spawn in the Hudson River in May through
July (Bain, 1997), while spawning in the St. Lawrence
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River occurs in June through July (Caron et al., 2002).
The SRT also considered genetics data to further inform its
decisions as to whether there is discreteness amongst Atlantic sturgeon
subpopulations. Genetics analyses for Atlantic sturgeon using
mitochondrial DNA (mtDNA), which is maternally inherited, and nuclear
DNA (nDNA), which reflects the genetics of both parents, have
consistently shown that Atlantic sturgeon subpopulations are
genetically diverse and that individual subpopulations can be
differentiated (Bowen and Avise, 1990; Ong et al., 1996; Waldman et
al., 1996a; Waldman et al., 1996b; Waldman and Wirgin, 1998; Waldman et
al., 2002; King et al., 2001; Wirgin et al., 2002; Wirgin et al., 2005;
Wirgin and King supplemental data, 2006; Grunwald et al., 2008). New
analyses of both mtDNA and nDNA were conducted specifically for the
status review. In comparison to previous studies, the genetic analyses
for the status review employed greater sample sizes from multiple
rivers, and limited the samples analyzed to those collected from YOY
and mature adults (> 130 cm TL) to ensure that the fish originated from
the river in which it was sampled (Wirgin and King supplemental data,
2006; ASSRT, 2007). The results for both the mtDNA haplotype and
microsatellite (nDNA) allelic frequencies indicated that all of the
Atlantic sturgeon subpopulations for which there are samples available
are genetically differentiated (ASSRT, 2007; Tables 4 and 5) from each
other. The results of the mtDNA analysis used for the status review
report were also subsequently published by Grunwald et al. (2008). In
comparison to the mtDNA analyses used for the status review report,
Grunwald et al. used additional samples, some from fish in the size
range (< 130 cm TL) excluded by Wirgin and King (supplemental data,
2006) because they were smaller than those considered to be mature
adults. Nevertheless, the results were the same and demonstrated that
each of the 12 sampled Atlantic sturgeon subpopulations could be
genetically differentiated from each other (Grunwald et al., 2008).
Genetic distances and statistical analyses (bootstrap values and
assignment test values) were also used to investigate significant
relationships among, and differences between, Atlantic sturgeon
subpopulations (ASSRT, 2007, Table 6 and Figures 16-18). Overall, the
genetic markers used in this analysis resulted in an average accuracy
of 88 percent for determining a sturgeon's natal river origin, but an
average accuracy of 94 percent for correctly classifying it to one of
five population groups (Kennebec River, Hudson River, James River,
Albemarle Sound, and Savannah/Ogeechee/Altamaha Rivers) when using
microsatellite data collected only from YOY and adults. A phylogenetic
tree (neighbor joining tree) was produced from only YOY and adult
samples (to reduce the likelihood of including strays from other
subpopulations) using the microsatellite analysis. Bootstrap values
(which measure how consistently the data support the tree structure)
for this tree were for analyses of: (1) 12 loci of samples collected
from YOY and adults; and (2) 7 loci for samples of YOY, subadult, and
adult Atlantic sturgeon (ASSRT, 2007, Figures 16-18). Classification
success rate averaged 79.0 percent for determining a sturgeon's natal
river and 86.9 percent for correctly classifying sturgeon to one of
five population groups (Kennebec River, Hudson River, James River,
Albemarle Sound, and Savannah/Ogeechee/Altamaha Rivers) (ASSRT, 2007).
Regarding sturgeon from northeast rivers, this analysis resulted in a
range of 81 to 89 percent accuracy in determining a sturgeon's natal
river of origin and correctly classifying a sturgeon to a population
group. To further assess the accuracy of the results, King
(supplemental data, 2006) reanalyzed the nDNA using a greater number of
loci. His results showed that increasing the number of loci from 7 to
12 improved the classification rates for natal origin and
identification of population groupings (e.g., from 84 percent to 95
percent for the James River), but did not change the conclusion that
there are five discrete Atlantic sturgeon population segments in the
United States.
In summary, evidence to support that there are discrete Atlantic
sturgeon populations includes temporal and spatial separation during
spawning and the results from genetic analyses. Genetic samples for YOY
and spawning adults were not available for river populations
originating from other rivers in the northeast region. However, nDNA
from an expanded dataset that included juvenile Atlantic sturgeon was
used to produce a neighbor-joining tree with bootstrap values (ASSRT,
2007; Figure 18). This dataset included additional samples from the
Delaware River and York River populations in the Northeast. Atlantic
sturgeon river populations also grouped into five population segments
in this analysis (Delaware River population with the Hudson River
population, and York River population with the James River population).
We have considered the information on Atlantic sturgeon population
structuring provided in the status review report and Grunwald et al.
(2008) and have concluded that five discrete Atlantic sturgeon
population segments are present in the United States, with three
located in the Northeast: (1)--The ``Gulf of Maine (GOM)'' population
segment, which includes Atlantic sturgeon that originate from the
Kennebec River, (2)--the ``New York Bight (NYB)'' population segment,
which includes Atlantic sturgeon originating from the Hudson and
Delaware Rivers, and (3)--the ``Chesapeake Bay (CB)'' population
segment, which includes Atlantic sturgeon that originate from the James
and York Rivers. Each is markedly separate from the other four
population segments as a consequence of physical factors.
With respect to Atlantic sturgeon of Canadian origin, mtDNA
analysis has shown that Atlantic sturgeon originating from rivers
ranging from the Kennebec River, Maine, to the Saint Lawrence River,
Canada, are predominately homogenous (one genotype) (Waldman et al.,
2002; Grunwald et al., 2008; ASSRT, 2007). However, nDNA microsatellite
analysis has found these same rivers to be genetically diverse (King,
supplemental data, 2006). The SRT concluded that the differences in
nDNA were sufficient to determine that Atlantic sturgeon which
originate in Canada are markedly separate from Atlantic sturgeon of
U.S. origin.
The genetic analyses support that at least one, and possibly more,
discrete Atlantic sturgeon population groupings occur in Canada. The
SRT did not further consider the status of Atlantic sturgeon
originating in Canada once it was determined that they were discrete
from the five U.S. Atlantic sturgeon population groupings. We did not
consider a listing determination for these populations given the lack
of information by which to determine whether the Canadian
subpopulations represent one or more DPSs, and given the regulatory
controls on import and export of Atlantic sturgeon and their parts per
the Convention on International Trade in Endangered Species of Wild
Flora and Fauna (CITES).
Significance
When the discreteness criterion is met for a potential DPS, as it
is for the GOM, NYB, and CB population segments in the Northeast
identified above, the second element that must be considered
[[Page 61877]]
under the DPS policy is significance of each DPS to the taxon as a
whole. The DPS policy cites examples of potential considerations
indicating significance, including: (1) Persistence of the discrete
population segment in an ecological setting unusual or unique for the
taxon; (2) evidence that loss of the discrete population segment would
result in a significant gap in the range of the taxon; (3) evidence
that the DPS represents the only surviving natural occurrence of a
taxon that may be more abundant elsewhere as an introduced population
outside its historic range; or, (4) evidence that the discrete
population segment differs markedly from other populations of the
species in its genetic characteristics.
We believe that the five discrete Atlantic sturgeon population
segments persist in ecological settings unique for the taxon. This is
evidenced by the fact that spawning habitat of each population grouping
is found in separate and distinct ecoregions that were identified by
The Nature Conservancy (TNC) based on the habitat, climate, geology,
and physiographic differences for both terrestrial and marine
ecosystems throughout the range of the Atlantic sturgeon along the
Atlantic coast (Figure 1).
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TNC descriptions do not include detailed information on the
chemical properties of the rivers within each ecoregion, but include an
analysis of bedrock and surficial geology type because it relates to
water chemistry, hydrologic regime, and substrate. It is well
established that waters have different chemical properties (i.e.,
identities) depending on the geology of where the waters originate. For
example, riverine spawning/nursery habitat of the Kennebec River
subpopulation occurs within the Northern Appalachian/Boreal Forest
ecoregion whose characteristically large expanses of forest, variety of
swamps, marshes, bogs, ice scoured riverbanks, salt marshes, and rocky
coastal cliffs were influenced by a geological history that includes
four glaciation events (TNC, 2008). In contrast, riverine spawning/
nursery habitat of Atlantic sturgeon that originate from the Hudson and
Delaware Rivers occurs within the Lower New England-Northern Piedmont
and North Atlantic Coast ecoregions which are characterized by low
mountains, abundant lakes, and limestone valleys inland and generally
[[Page 61879]]
flat, sandy coastal plains dissected by major tidal river systems near
the coast (Barbour, 2000; TNC, 2008). The Chesapeake Bay Lowlands
ecoregion, within which riverine spawning/nursery habitat for the James
River population grouping of Atlantic sturgeon occurs, presents yet a
different landscape based on its geologic history. As glaciers that
extended as far south as present day Pennsylvania began to melt,
streams and rivers that flowed toward the coast were carved out of the
landscape (Pyzik et al., 2004). These past events are seen today in the
characteristic features of the Chesapeake Bay Lowlands ecoregion which
includes a broad plain to the west of the Bay with generally low slopes
and gentle drainage dissected by a series of major rivers--the
Patuxent, Potomac, Rappahannock, York and James--as well as a complex
and dynamic patchwork of barrier islands, salt marshes, tidal flats and
large coastal bays along the Delmarva Peninsula (TNC, 2002 in draft).
Riverine spawning/nursery habitat for the two remaining Atlantic
sturgeon groupings in the Southeast likewise occur in separate and
distinct ecoregions. Therefore, the ecoregion delineations support that
the physical and chemical properties of the Atlantic sturgeon spawning
rivers are unique to each population grouping. The five discrete U.S.
Atlantic sturgeon population segments are ``significant'' as defined in
the DPS policy, given that the spawning rivers for each population
segment occur in a unique ecological setting.
Further, because each discrete population segment is genetically
distinct and reproduces in a unique ecological setting, the loss of any
one of the discrete population segments is likely to create a
significant gap in the range of the taxon. Atlantic sturgeon that
originate from other discrete population segments are not expected to
re-colonize systems except perhaps over a long time frame (e.g.,
greater than 100 years), given that gene flow is low between the five
discrete population segments (Secor and Waldman, 1999) and the
geographic distances between spawning rivers of different population
segments are relatively large (ASSRT, 2007). Therefore, the loss of any
of the discrete population segments would result in a significant gap
in the range of Atlantic sturgeon, and negatively impact the species as
a whole, given the strong natal homing behavior of the species.
In summary, the five Atlantic sturgeon discrete population segments
meet the significance criterion of the DPS policy because they each
persist 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. As described in the status review report, the SRT
concluded that these five population segments of Atlantic sturgeon
within the United States (identified above) should be considered
significant under the DPS policy guidelines. We, therefore, concur with
the SRT's conclusion that five Atlantic sturgeon DPSs occur within the
United States. The five DPSs are hereafter referred to as: (1) GOM, (2)
NYB, (3) CB, (4) Carolina, and (5) South Atlantic DPSs (Figure 2).
[[Page 61880]]
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Current Status of the GOM, NYB, and CB DPSs
After completing the DPS analysis, we next considered the current
status of the three DPSs that occur within the Northeast Region's
jurisdiction, the GOM, NYB, and CB DPSs, as well as the factors
affecting each of these Atlantic sturgeon DPSs in relation to the ESA's
standards for listing (see Analysis of Factors, below). The ESA and its
implementing regulations require listing determinations to be based on
the current status of the species and the factors presently affecting
the species or likely to affect the species in the future.
Many of the activities causing harm to Atlantic sturgeon have
occurred for years, even decades. Similarly, some conservation actions
have been in place for years (e.g., prohibition on catch and retention
of Atlantic sturgeon). The past impacts of human activity on the GOM,
NYB, and CB DPSs cannot be particularized in their entirety.
[[Page 61881]]
However, to the extent they have manifested themselves at the
population level, such past impacts are subsumed in the information
presented on their current status, recognizing that the benefits to
these Atlantic sturgeon DPSs as a result of conservation activities
already implemented may not be evident in the status and trend of the
DPS for years, given the relatively late age to maturity for Atlantic
sturgeon and depending on the age class(es) affected.
Gulf of Mexico (GOM) DPS
The GOM DPS includes all Atlantic sturgeon whose range occurs in
watersheds from the Maine/Canadian border and extending southward to
include all associated watersheds draining into the Gulf of Maine as
far south as Chatham, MA, as well as wherever these fish occur in
coastal bays, estuaries, and the marine environment from the Bay of
Fundy, Canada, to the Saint Johns River, FL. Within this range,
Atlantic sturgeon have been documented from the following rivers:
Penobscot, Kennebec, Androscoggin, Sheepscot, Saco, Piscataqua, and
Merrimack. The Kennebec River is currently the only known spawning
river for the GOM DPS. Evidence of Atlantic sturgeon spawning in other
rivers of the GOM DPS is not available. However, Atlantic sturgeon
continue to use these historical spawning rivers and may represent
additional spawning groups (ASSRT, 2007). The majority of historical
Atlantic sturgeon spawning habitat is accessible in all but the
Merrimack River of the GOM DPS. Therefore, the availability of spawning
habitat does not appear to be the reason for the lack of observed
spawning in other GOM DPS rivers. However, whether Atlantic sturgeon
spawning habitat in the GOM DPS is fully functional is difficult to
quantify.
Known threats to Atlantic sturgeon of the GOM DPS include effects
to riverine habitat (e.g., dredging, water quality) as well as threats
that occur throughout their marine range (e.g., fisheries bycatch).
There are no current abundance estimates for the GOM DPS of Atlantic
sturgeon. The CPUE of subadult Atlantic sturgeon in a multi-filament
gillnet survey conducted on the Kennebec River was considerably greater
for the period of 1998-2000 (CPUE=7.43) compared to the CPUE for the
period 1977-1981 (CPUE = 0.30). The CPUE of adult Atlantic sturgeon
showed a slight increase over the same time period (1977-1981 CPUE =
0.12 versus 1998-2000 CPUE = 0.21) (Squiers, 2004). There is also new
evidence of Atlantic sturgeon presence in rivers (e.g., the Saco River)
where they have not been observed for many years.
New York Bight (NYB) DPS
The NYB DPS includes all Atlantic sturgeon whose range occurs in
watersheds that drain into coastal waters, including Long Island Sound,
the New York Bight, and Delaware Bay, from Chatham, MA to the Delaware-
Maryland border on Fenwick Island, as well as wherever these fish occur
in coastal bays, estuaries, and the marine environment from the Bay of
Fundy, Canada, to the Saint Johns River, FL. Within this range,
Atlantic sturgeon have been documented from the Hudson and Delaware
rivers as well as at the mouth of the Connecticut and Taunton rivers,
and throughout Long Island Sound. There is evidence to support that
spawning occurs in the Hudson and Delaware Rivers. Evidence of Atlantic
sturgeon spawning in the Connecticut and Taunton Rivers is not
available. However, Atlantic sturgeon continue to use these historical
spawning rivers (ASSRT, 2007). The majority of historical spawning
habitat is accessible to the NYB DPS. Therefore, the availability of
spawning habitat does not appear to be the reason for lack of observed
spawning in the Connecticut and Taunton Rivers. However, whether
Atlantic sturgeon spawning habitat in these rivers is fully functional
is difficult to quantify.
Known threats to Atlantic sturgeon of the NYB DPS include effects
to riverine habitat (e.g., dredging, water quality, and vessel strikes)
as well as threats that occur throughout their marine range (e.g.,
fisheries bycatch). The only abundance estimate for Atlantic sturgeon
belonging to the NYB DPS is 870 spawning adults per year for the Hudson
River subpopulation, based on data collected from 1985-1995 (Kahnle et
al., 2007). The accuracy of the estimate may be affected by bias in the
reported harvest or estimated exploitation rate for that time period
(Kahnle et al., 2007). Underreporting of harvest would have led to
underestimates of stock size, while underestimates of exploitation
rates would have resulted in overestimates of stock size (Kahnle et
al., 2007). In addition, the current number of spawning adults may be
higher given that the estimate is based on the time period prior to the
moratorium on fishing for and retention of Atlantic sturgeon.
There is no abundance estimate for the Delaware River
subpopulation. Delaware's Department of Natural Resources and
Environmental Control (DNREC) has been conducting surveys for Atlantic
sturgeon since 1991 (DNREC, 2009). Atlantic sturgeon are a Delaware
endangered species (state-listed).
CB DPS
The CB DPS includes all Atlantic sturgeon whose range occurs in
watersheds that drain into the Chesapeake Bay and into coastal waters
from the Delaware-Maryland border on Fenwick Island to Cape Henry, VA,
as well as wherever these fish occur in coastal bays, estuaries, and
the marine environment from the Bay of Fundy, Canada, to the Saint
Johns River, FL. Within this range, Atlantic sturgeon have been
documented from the James, York, Potomac, Rappahannock, Pocomoke,
Choptank, Little Choptank, Patapsco, Nanticoke, Honga, and South rivers
as well as the Susquehanna Flats. Historical evidence suggests that
several of these, including the James, York, Potomac, Susquehanna, and
Rappahannock Rivers, were Atlantic sturgeon spawning rivers. However,
the James River is currently the only known spawning river for the CB
DPS. Evidence of Atlantic sturgeon spawning in other rivers of the CB
DPS is not available, although spawning is suspected to occur in the
York based on genetics data and anecdotal reports. The majority of
historical Atlantic sturgeon spawning habitat is accessible, but it is
unknown whether it is fully functional.
Known threats to Atlantic sturgeon of the CB DPS include effects to
riverine habitat (e.g., dredging, water quality, vessel strikes) as
well as threats that occur throughout their marine range (e.g.,
fisheries bycatch). There are no current abundance estimates for the CB
DPS. The Maryland Reward Program has resulted in the documentation of
over 1,133 wild Atlantic sturgeon since 1996. The Virginia Atlantic
sturgeon reward program in the Chesapeake Bay documented and measured
295 Atlantic sturgeon in 1997 and 1998 (Spells, 2007). However, since
sturgeon from multiple DPSs occur in the Chesapeake Bay, it is unlikely
that all of the sturgeon captured in either reward program originated
from the CB DPS.
Analysis of Factors Affecting the Three Northeast Region DPSs of
Atlantic Sturgeon
A species shall be listed if the Secretary of Commerce determines,
on the basis of the best scientific and commercial data available after
conducting a review of the species' status, that the species is in
danger of extinction throughout all or a significant portion of its
range (i.e., ``endangered'')
[[Page 61882]]
or is likely to become an endangered species within the foreseeable
future throughout all or a significant portion of its range (i.e.,
``threatened'') because of any one or a combination of the following
factors: (1) The present or threatened destruction, modification, or
curtailment of its habitat or range; (2) over utilization for
commercial, recreational, scientific, or educational purposes; (3)
disease or predation; (4) the inadequacy of existing regulatory
mechanisms; or (5) other natural or manmade factors affecting its
continued existence.
The SRT took a multi-step approach for each DPS to answer whether
there were: (1) Sufficient data to conclude whether a DPS is threatened
or endangered; (2) sufficient data to conclude that a DPS was not
threatened or endangered; or (3) insufficient data to allow a full
assessment of the populations within a DPS. The SRT identified the
threats specific to Atlantic sturgeon and then used a semi-quantitative
approach to assess the overall effect of those threats to each DPS
(ASSRT, 2007; Patrick and Damon-Randall, 2008).
The ESA does not define what timeframe corresponds with the phrase
``within the foreseeable future'' in its definition of the term
``threatened.'' Therefore, before beginning the analysis of the Section
4(a)(1) factors, it was necessary for the SRT to define the timeframe
(Patrick and Damon-Randall, 2008). Following the example of a past
status review team (Acropora Biological Review Team, 2005), the
Atlantic sturgeon SRT determined that the appropriate period of time
would: (1) Depend on the particular kinds of threats; (2) consider the
life history characteristics of the species; (3) consider specific
habitat requirements for the species; and (4) allow for the
conservation and recovery of the species and the ecosystems upon which
it depends (ASSRT, 2007; Patrick and Damon-Randall, 2008). Based on
these, the SRT agreed that 20 years would be the appropriate timeframe
for defining ``the foreseeable future'' for Atlantic sturgeon (ASSRT,
2007; Patrick and Damon-Randall, 2008). The SRT also concluded that 20
years is an appropriate timeframe for determining the status of a
species, as it was not too far into the future that qualitative
analysis would prove to be ineffective or unreliable, it allowed
sufficient time (10+ years) to determine the productivity of Atlantic
sturgeon subpopulations using standardized protocols (Sweka et al.,
2006), and it is the approximate age of maturity for Atlantic sturgeon
or is approximately equal to one generation (Scott and Crossman, 1973;
Smith et al., 1982; Young et al., 1998).
The Present or Threatened Destruction, Modification, or Curtailment of
the Species' Habitat or Range
The SRT identified barriers (i.e., dams, tidal turbines), dredging,
and water quality (e.g., dissolved oxygen levels, water temperature,
and contaminants) as threats that affect Atlantic sturgeon habitat or
range. The SRT did not specifically consider global climate change.
Since completion of the SRT report, additional information has become
available on the effects of global climate change in the Northeast and
Mid-Atlantic where habitat for the GOM, NYB, and CB DPSs occurs.
As noted in the status review report, dams for hydropower
generation, flood control, and navigation have the potential to affect
Atlantic sturgeon by impeding access to spawning and foraging habitat,
modifying free-flowing rivers to reservoirs, and altering downstream
flows and temperatures. Turbines for power generation could, similarly,
impede access to spawning and foraging habitat but are also known to
injure and kill sturgeon as a result of direct contact with the turbine
blades. Environmental impacts of dredging include direct removal or
burial of organisms, elevated turbidity or siltation, contaminant
resuspension, noise or disturbance, alterations to hydrodynamic regime
and physical habitat, and loss of riparian habitat (Chytalo, 1996;
Winger et al., 2000). Water quality can be affected by many activities
such as industrial activities, forestry, agriculture, land development
and urbanization that can result in discharges of pollutants, changes
in water temperature and dissolved oxygen levels, alteration of water
flow, and the addition of nutrients or sediment from erosion. Any of
these can affect sturgeon at various life stages depending on the
extent of the threat and the life stage affected. There is a large and
growing body of literature on past, present, and future impacts of
global climate change induced by human activities--commonly referred to
as ``global warming.'' Some of the likely effects commonly mentioned
are sea level rise, increased frequency of severe weather events, and
change in air and water temperatures.
Dams
The SRT used GIS tools and dam location data collected by Oakley
(2005) to determine the number of miles of available habitat in rivers
where Atlantic sturgeon historically spawned. As previously described,
within the GOM DPS, Atlantic sturgeon are known to spawn in the
Kennebec River. The Penobscot, Sheepscot, Androscoggin, and Merrimack
Rivers are known to have supported spawning in the past (ASSRT, 2007).
Atlantic sturgeon occur in the Saco and Piscataqua Rivers, although
there is no information on historical or current spawning activity for
Atlantic sturgeon in these rivers (ASSRT, 2007; J. Sulikowski, UNE,
pers. comm., 2009).
Historically, the upstream migration of Atlantic sturgeon in the
Kennebec River was limited to Waterville, ME, which is the location of
Ticonic Falls (river kilometer (rkm) 98) (NMFS and USFWS, 1998). The
construction of Edwards Dam in 1837, downstream of the Ticonic Falls,
denied Atlantic sturgeon access to historical habitat in the Kennebec
River until 1999 when the dam was removed. Since its removal, access to
100 percent of historical habitat has been restored. In the
Androscoggin River, the Brunswick Hydroelectric Dam is located at the
head-of-tide near the site of the natural falls. The location of
historical spawning grounds on the Androscoggin is unknown, but it is
unlikely that Atlantic sturgeon could navigate the natural falls
located at Brunswick Dam (NMFS and USFWS, 1998). Therefore, the dam is
unlikely to have limited access of Atlantic sturgeon to their spawning
habitat. Similarly, Atlantic sturgeon upstream migration within the
Sheepscot River is thought to have been historically limited to the
lower river (rkm 32) just below the first dam on the river (rkm 35);
therefore, 100 percent of the historical habitat (based on river
kilometers) is available to Atlantic sturgeon in the Sheepscot.
In contrast to the aforementioned rivers, access to Atlantic
sturgeon spawning habitat is impeded on the Penobscot River.
Historically, the falls at Milford, rkm 71, were likely the first
natural obstacle to Atlantic sturgeon migration on the Penobscot River
(L. Flagg, MEDMR, pers. comm., 1998). In 1833, the Veazie Dam was
constructed on the Penobscot River at rkm 56, blocking 21 percent of
Atlantic sturgeon habitat. In 1875, the Treats Falls Bangor Dam was
built five kilometers downstream of the Veazie, which also impeded
migration upstream (ASSRT, 2007). However, this dam was breached in
1977 (ASSRT, 2007). Therefore, 79 percent of Atlantic sturgeon habitat
is currently accessible on the Penobscot (ASSRT, 2007). In 2008, the
Penobscot River Restoration Trust, a non-profit corporation, exercised
its option to purchase the Veazie and two other dams
[[Page 61883]]
on the Penobscot (ASSRT, 2007). In doing so, the Trust has the right
to, in part, decommission or remove the Veazie Dam, thus reopening
miles of habitat for Atlantic sturgeon and other diadromous species
(ASSRT, 2007). However, funds for the removal need to be generated and
permits need to be secured, and it remains uncertain whether all of the
goals will be achieved. If Atlantic sturgeon were able to ascend the
falls at Milford, they could have migrated without obstruction to
Mattaseunk (rkm 171) (ASSRT, 2007). However, evidence is lacking to say
with certainty that Atlantic sturgeon were able to ascend the falls at
Milford.
Information on Atlantic sturgeon use of the Saco River in Maine
became available after completion of the status review report. The last
focused study of the Saco River was almost 30 years ago, and continued
use of the river by Atlantic sturgeon was uncertain at the time of the
status review report. However, Atlantic sturgeon have been captured
during routine trawl sampling in the river during 2008 and 2009 as part
of a 2-year monitoring project of the Saco River/Estuary. Tagging and
tracking of the captured fish has shown that Atlantic sturgeon are
making use of the river up to the Cataract Dam (J. Sulikowski, UNE,
pers. comm., 2009), the first dam on the river at approximately rkm 6
(Atlantic Salmon Commission, 1983). There are several dams on the Saco
River known to have blocked fish passage for species such as Atlantic
salmon, shad, and alewives (MEDMR, 1994). The effect of such dams on
the Atlantic sturgeon that currently use the river is unknown.
Likewise, there are several dams on the Piscataqua River, and the
effect of such dams on the Atlantic sturgeon that currently use the
river is unknown.
Within the GOM DPS, access to historical spawning habitat is most
severely impacted in the Merrimack River (ASSRT, 2007). Hoover (1938)
identified Amoskeag Falls (rkm 116) as the historical limit for
Atlantic sturgeon in the Merrimack River. In the 1800s, construction of
the Essex Dam in Lawrence, MA (rkm 49) blocked the migration of
Atlantic sturgeon to 58 percent of its historically available habitat
(Oakley, 2003; ASSRT, 2007). Tidal influence extends to rkm 35;
however, in the summer months when river discharge is lowest, the salt
wedge extends upriver, resulting in approximately 19 km of tidal
freshwater and 9 km of freshwater habitat (Keiffer and Kynard, 1993).
Based on a detailed description by Keiffer and Kynard (1993), the
accessible portions of the Merrimack seem to be suitable for Atlantic
sturgeon spawning and nursery habitat. Nevertheless, the presence of
the dam means that only 42 percent of historical Atlantic sturgeon
habitat is currently available (ASSRT, 2007).
Within the NYB DPS, there is evidence of Atlantic sturgeon spawning
in the Hudson and Delaware Rivers (ASSRT, 2007). Historical records
indicate that Atlantic sturgeon spawned in the Taunton River at least
until the turn of the century (ASSRT, 2007), and also occurred in the
Connecticut River (Judd, 1905; Murawski and Pacheco, 1977; Secor, 2002;
ASSRT, 2007). By 1898, the overall New England harvest of Atlantic
sturgeon was quite low, 36 mt, and only occurred in Maine,
Massachusetts, and Connecticut (Secor, 2002). There is no recent
evidence (within the last 15 years) to confirm that spawning currently
occurs in either the Taunton or Connecticut Rivers (ASSRT, 2007).
Atlantic sturgeon are present in both rivers, and likely represent
sturgeon originating from other spawning rivers along the coast.
In general, Atlantic sturgeon access to historical or spawning
habitat believed to be historical is relatively unimpeded on all four
of these NYB DPS rivers. The first impediment to migrating Atlantic
sturgeon on the Hudson River is the Federal Dam located at Troy, NY
(ASSRT, 2007). This dam location is upstream of Catskill (rkm 204),
which is the northern extent of Atlantic sturgeon spawning and nursery
habitat (Kahnle et al., 1998). Therefore, 100 percent of Atlantic
sturgeon habitat is still available on the Hudson (ASSRT, 2007).
Similarly, 100 percent of Atlantic sturgeon habitat is believed to be
accessible on the Delaware River where 140 rkm of Atlantic sturgeon
habitat are available extending from Delaware Bay to the fall line at
Trenton, NJ with no dams present (ASSRT, 2007). Historical upstream
migration of Atlantic sturgeon in the Taunton River is unknown.
However, Atlantic sturgeon have access to 89 percent of the river
downstream of the Town River Pond Dam (ASSRT, 2007). Similarly, it is
not clear how far up the Connecticut River Atlantic sturgeon
historically migrated. In all but low flow years, it is likely that
Atlantic sturgeon could pass the Enfield Rapids prior to dam
construction (Enfield Dam), which occurred in three stages between 1829
and 1881 (Judd, 1905). The falls at South Hadley, MA, which is now the
site of the Holyoke Dam, are considered the upstream limit of sturgeon
in this system; however, there is one historical record of an Atlantic
sturgeon sighted as far upstream as Hadley, MA (24 rkm upstream from
South Hadley) (ASSRT, 2007). Also, in 2006 an Atlantic sturgeon was
taken in the fish lift at the Holyoke Dam (R. Murray, HG&E, pers.
comm., 2006). Since the Enfield Dam has been breached, an additional 90
km of habitat are available, and depending on the interpretation of
historical spawning grounds, either 100 percent (Holyoke Dam, South
Hadley, MA), or 86 percent (Hadley, MA) of historical Atlantic sturgeon
habitat is available (ASSRT, 2007).
For the CB DPS, there is evidence that Atlantic sturgeon currently
spawn in the James River (ASSRT, 2007). The observed presence of YOY
and adult sturgeon in the York River suggests that spawning may still
occur there (Musick et al., 1994; K. Place, Commercial Fisherman, pers.
comm., 2006; ASSRT, 2007). The Susquehanna, Potomac, Rappahannock, and
Nanticoke Rivers also supported Atlantic sturgeon spawning in the past,
but there is no conclusive evidence that spawning still occurs in any
of these rivers (ASSRT, 2007). Based on the review by Oakley, 100
percent of Atlantic sturgeon habitat is currently accessible in these
rivers (ASSRT, 2007). Although dams are present, most are located
upriver of where spawning is expected to have historically occurred.
For example, four dams were constructed from 1904-1932 on the
Susquehanna River, but none of these dams are suspected to have impeded
Atlantic sturgeon spawning habitat as the lowermost dam (Conowingo) is
located above the suspected historical spawning grounds (Steve
Minkkinen, USFWS, pers. comm., 2006). The Embrey Dam was built in 1910
above the fall line of the Rappahannock River and may have blocked the
upstream migration of Atlantic sturgeon (ASSRT, 2007). This dam was
breached in 2004 and 100 percent of historical Atlantic sturgeon
habitat is believed to be accessible (ASSRT, 2007).
Dredging
Dredging and filling operations can impact important features of
Atlantic sturgeon habitat because they disturb benthic fauna, eliminate
deep holes, and alter rock substrates necessary for spawning (Smith and
Clugston, 1997). Deposition of dredge sediment has been shown to affect
the distribution of Atlantic sturgeon (Hatin et al., 2007). Dredging
can also result in direct takes (killing and injuring) of Atlantic
sturgeon. Such takes have the potential to affect the range of Atlantic
sturgeon if the takings contribute to the extirpation of a DPS.
Dickerson (2006) summarized observed takings of Gulf, shortnose,
and
[[Page 61884]]
Atlantic sturgeon from dredging activities conducted by the Army Corps
of Engineers (ACOE) in the United States; overall 24 sturgeon (2 Gulf,
11 shortnose, and 11 Atlantic sturgeon) were observed during the years
of 1990-2005. Of the 24 sturgeon captured, 15 (62.5 percent) were
reported as dead. The ASSRT calculated a minimum take of 0.6 Atlantic
sturgeon per year based on hopper dredge takes since 1995 and given
that dredging efforts were relatively similar among years (ACOE, 2006).
Both of these are considered minimum estimates since observed takes of
Atlantic sturgeon are documented incidental to observer coverage of
dredging activities for other, already listed, ESA-species (e.g.
shortnose sturgeon and sea turtles). Given that Atlantic sturgeon do
not have the same temporal and spatial distribution as these ESA-listed
species, it is likely that Atlantic sturgeon takes occur during
unobserved dredging operations.
Dredging projects on the Kennebec River in the GOM DPS are known to
have captured Atlantic sturgeon. Dredging has also been proposed for
the Penobscot Harbor of the Penobscot River (ASSRT, 2007). Capture of
Atlantic sturgeon is likely to occur if dredging takes place at times
when Atlantic sturgeon are present in the area. NMFS can currently
request, but cannot require, dredge operations to be modified to
minimize capture and injury of Atlantic sturgeon.
Within the NYB DPS, the commercial shipping channel of the Hudson
River is maintained at a depth of 9.75 m (at mean low water) for nearly
the entire length of the river to the Port of Albany. However, the
section between Haverstraw Bay and Catskill (approximately rkm 122) is
naturally deep and does not require dredging (D. Mann-Klager, FWS,
pers. comm., 1998).
The navigation channel in the Delaware River similarly undergoes
maintenance dredging from the mouth of Delaware Bay to just north of
Trenton, NJ (ASSRT, 2007). Seasonal restrictions on when this work can
occur have been imposed by the Delaware River Fish and Wildlife
Management Cooperative to reduce impacts from dredging on diadromous
species (ASSRT, 2007). Nevertheless, dredge gear used in the Delaware
is known to injure or kill Atlantic sturgeon (ASSRT, 2007). There are
also new proposed dredge activities in the Delaware River. In 2006,
Crown Landing, LLC, was approved by the Federal Energy Regulatory
Commission (FERC) to construct and operate a liquefied natural gas
(LNG) import terminal on the Delaware River near Logan, New Jersey (rkm
126). The construction of the LNG terminal would require the hydraulic
dredging of 1.24 million m\3\ in the first year of construction
followed by maintenance dredging of 67,000-97,000 m\3\/year. Dredge
spoil will be deposited in an upland disposal site, and dredging will
be limited to the months of August through December. The dredging
operations proposed for construction and maintenance of the LNG
terminal would occur, in part, directly in suspected historical
Atlantic sturgeon spawning habitat (Fox, 2006; ASSRT, 2007). However,
construction of the terminal has not yet begun, and it is uncertain
whether it will proceed since approval from the State of Delaware has
not been secured (Examiner.com, 2009).
Since completion of the SRT report, we have received information on
the Delaware River Main Channel Deepening project, which calls for the
deepening of the existing channel from 40 to 45 feet (12.2 to 13.7
meters) from Philadelphia Harbor, PA, to the mouth of the Delaware Bay.
This project will require dredging the channel with hydraulic and
hopper dredges and blasting approximately 77,000 cubic yards (58,914
cubic meters) of rock near Marcus Hook, PA. While the seasonal
restrictions imposed by the Delaware River Fish and Wildlife Management
Cooperative may help to reduce or prevent direct take of important
resident fish species (primarily the federally endangered shortnose
sturgeon and other species of diadromous fishes), there is still the
potential for direct impacts of this project on Atlantic sturgeon as
they may be found in the project area throughout the year. There is the
potential for indirect effects as well, such as changes in hydrology of
the river, which may affect possible spawning habitat (e.g., salt water
intruding further into the river). The location of spawning habitat for
Atlantic sturgeon in the Delaware River has not been confirmed (ASSRT,
2007).
For Atlantic sturgeon belonging to the CB DPS, the most significant
impacts to spawning habitat likely occurred in 1843 and 1854 in the
James River when granite outcropping consisting of large and small
boulders was removed and the river was dredged to improve ship
navigation (Holton and Walsh, 1995; Bushnoe et al., 2005). Similarly,
rock was removed from Drewry's Island Channel in 1878 to improve
navigation (Holton and Walsh, 1995). These granite outcroppings and
boulder matrices are the types of habitats that are believed to be
ideal spawning habitats for Atlantic sturgeon (Bushnoe et al., 2005).
Based on commercial landings (Bushnoe et al., 2005), the James River
likely supported the largest subpopulation in the Chesapeake Bay in the
1800s.
Dredging continues to pose a threat to Atlantic sturgeon in the
James River. There are dredging projects underway to deepen and widen
the shipping terminal near Richmond on the James River, and the river
undergoes maintenance dredging on almost an annual basis to allow
commercial ocean-going vessels to reach the Richmond terminal (C.
Hager, VIMS, pers. comm., 2005; S. Powell, ACOE, pers. comm., 2009).
Since 1998, six new permits have been issued for dredging within the
James River, and an additional 24 maintenance projects have been
approved (L. Gillingham, VMRC, pers. comm., 2005). The Commonwealth of
Virginia does impose a dredging moratorium during the anadromous
spawning season (C. Hager, VIMS, pers. comm., 2005). The ACOE has
received a waiver to dredge during this moratorium in very limited
circumstances such as to conduct a study to assess the effects of
dredging on sturgeon (S. Powell and S. Cameron, ACOE, pers. comm.,
2009).
Turbines
The placement of turbine structures to generate power in rivers
used by Atlantic sturgeon could, potentially, damage or destroy bottom
habitat. However, the more likely effect of turbines is injury and
death of Atlantic sturgeon as a result of being struck by the turbine
blades. Such takes have the potential to affect the range of Atlantic
sturgeon if the takings contribute to the extirpation of a DPS.
Seventeen hydrokinetic projects proposed for both the GOM (9) and
NYB (8) DPSs have received preliminary permits from FERC, with many
more projects being proposed. There are two tidal power projects
currently in operation along the range of Atlantic sturgeon. The
Annapolis River (Nova Scotia, Canada) tidal power plant, built in 1982,
was constructed as a demonstration site for marine Straflo turbines and
consists of a rock-filled dam housing the turbine and sluice gates (M.
Dadswell, Arcadia University, pers. comm., 2006). The negative impacts
of the Annapolis tidal turbine on Atlantic sturgeon (150-200 cm TL)
appear to be great, as the probability of lethal strike from the
turbine ranges between 40 and 80 percent (M. Dadswell, Arcadia
University, pers. comm., 2006; ASSRT, 2007), and at least three
severed, gravid females have been observed below the power plant
(Dadswell and Rulifson, 1994). In
[[Page 61885]]
summer 2009, nine severed Atlantic sturgeon carcasses were documented
on beaches near the Annapolis project (http://annapolisroyalheritage.blogspot.com/2009/09/atlantic-sturgeon.html).
Although the cause of mortality could not be confirmed, the injuries
are consistent with blade strikes from the tidal turbines. Since this
power plant occurs within the marine range of Atlantic sturgeon that
originate from the GOM, NYB, and CB DPSs, fish originating from these
DPSs could also be struck and killed or injured. One marine turbine
project is underway within the United States in the East River, New
York (Angelo, 2005; Verdant Power webpage, 2009). Although no impacts
to wildlife have been reported, the project is still in the early
stages. Verdant Power recently completed Phase 2 of the project, which
involved installation and operation of six full-scale turbines in an
array at the project site in the East River (Verdant Power webpage,
2009). Phase 3 of the project will entail placement of 30 turbines in
the east branch of the river and additional turbines in the west branch
if the company is able to acquire a license from FERC (Verdant Power
webpage, 2009). The energy company, Verdant Power, has plans to expand
the project to up to 300 turbines to be located within a 1-mile section
of the river near Roosevelt Island (Angelo, 2005).
Water Quality
The Northeast Coast region, which includes the coastal waters and
watersheds of Connecticut, Delaware, Maine, Maryland, Massachusetts,
New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island,
Vermont, and Virginia, is the most densely populated coastal region in
the United States (EPA, 2008). Therefore, it is not surprising that
water quality for the GOM, NYB, and CB DPSs continues to be an issue
likely affecting Atlantic sturgeon despite many positive actions (e.g.,
implementation of the Clean Water Act). Contaminants, including toxic
metals, polychlorinated aromatic hydrocarbons (PAHs), organophosphate
and organochlorine pesticides, polychlorinated biphenyls (PCBs), and
other chlorinated hydrocarbon compounds can have substantial
deleterious effects on aquatic life. Effects from these elements and
compounds on fish include production of acute lesions, growth
retardation, and reproductive impairment (Cooper, 1989; Sinderman,
1994). The coastal environment is also impacted by coastal development
and urbanization that result in storm water discharges, non-point
source pollution, and erosion. Secor (1995) noted a correlation between
low abundances of sturgeon during this century and decreasing water
quality caused by increased nutrient loading and increased spatial and
temporal frequency of hypoxic conditions. The SRT considered all of
this information as well as the second edition of the National Coastal
Condition Report (EPA, 2004), and concluded that water quality posed a
moderate to moderately low risk that the GOM, NYB, and CB DPSs were
likely to become endangered within the foreseeable future. Since
completion of the SRT report, the EPA has released the third National
Coastal Condition Report (EPA, 2008). That report is considered here to
aid in assessing the level of threat water quality poses to the GOM,
NYB, and CB DPSs.
Within the GOM DPS, water quality of its rivers and estuaries was
severely degraded as a result of many activities, including
agricultural and forestry practices, industrialization, and land
development. As late as 1994, the Androscoggin River was still
considered one of the most polluted rivers in the United States (EWG,
2005; Lichter et al., 2006). However, water quality in the Androscoggin
River has been improving (Lichter et al., 2006). Likewise, the
Penobscot River went through a period of very poor water quality
(Hatch, 1971; Davies and Tsomides, 1999; Courtemanch et al., 2009).
Pollutants such as mercury and dioxin persist in the river, but dioxin
levels in fish are showing improvement with a drop from 7.6 parts per
trillion in 1984 to less than 0.1 parts per trillion in 2004 (MEDEP,
2005). In addition, increasing numbers of shortnose sturgeon are being
found in the river (G. Zydelwski, ME DMR, pers. comm., 2009). Shortnose
sturgeon and Atlantic sturgeon are believed to have similar
sensitivities to pollutants (Dwyer et al., 2000). Therefore, increasing
numbers of shortnose sturgeon in the Penobscot River suggest that water
quality in the river is also suitable for supporting Atlantic sturgeon.
In 2003, the Merrimack River was the subject of a watershed
assessment conducted by the ACOE and municipalities along the river
(ASSRT, 2007). The study noted that the lower basin of the river was
highly urbanized with high levels of point and non-point source
pollution (USACOE, 2003; ASSRT, 2007). The study also noted impaired
dissolved oxygen levels and pH levels (ASSRT, 2007). The Merrimack
River watershed in New Hampshire was identified as a mercury hot spot
within the region (Evers et al., 2007; ASSRT, 2007). However, despite
these water quality assessment results, sampling studies indicate that
the shortnose sturgeon population in the river has increased over the
last decade. Likewise, anecdotal information indicates that more
Atlantic sturgeon are using the mouth of the river now than in years
past.
Despite the persistence of contaminants in rivers and increasing
land development, many rivers and watersheds within the range of the
GOM DPS have demonstrated improvement in water quality (EPA, 2008). In
general, the most recent (third edition) EPA Coastal Condition Report
identified that water quality was good to fair for waters north of Cape
Cod (EPA, 2008).
Rivers and watersheds in the NYB DPS have been similarly affected
by industrialization, agriculture, and urbanization that occurred since
European colonization. Water quality in the Taunton River has slightly
improved since 1970 (Taunton River Journal, 2006; ASSRT, 2007).
However, the river still suffers from low dissolved oxygen
concentrations in the summer and high ammonia-nitrogen levels (Taunton
River Journal, 2006; ASSRT, 2007). Treated wastewater from several
municipalities is added to the river daily, the majority of which is
produced from a single facility in one city (ASSRT, 2007). There are
currently no fish consumption advisories in effect for the Taunton
River (ASSRT, 2007).
Water quality on the Connecticut River has improved dramatically in
the last 40 years (ASSRT, 2007). It is now swimmable and fishable with
some downstream exceptions (T. Savoy, CTDEP, pers. comm., 2006). As a
result of the operations of a manufactured gas plant that was located
adjacent to the river, there are large, discrete coal tar deposits that
occupy an estimated 32.5 acres (13.16 hectares) below the Holyoke Dam.
Coal tar leachate has been suspected of impairing sturgeon reproductive
success. Kocan et al. (1993, 1996) conducted a laboratory study to
investigate the survival of shortnose sturgeon eggs and larvae exposed
to PAHs, a by-product of coal distillation. Only 5 percent of sturgeon
embryos and larvae survived after 18 days of exposure to Connecticut
River coal tar (i.e., PAHs), demonstrating that contaminated sediment
is toxic to shortnose sturgeon embryos and larvae under laboratory
exposure conditions. A remediation project was initiated in 2002 to
begin removing some of the coal tar deposits from the river. Between
2002 and 2006, 11,714 cubic yards (8,962.5 cubic meters) of coal tar
and associated sediments were removed. In
[[Page 61886]]
2006, information that was obtained through the removal process and
through diver surveys confirmed that the extent of the deposits was
much greater than initial estimates. Studies are being conducted to
determine if the weathered, hard tar that is present in much of the
area is less toxic and mobile than the soft tar and therefore, does not
pose the same risk. According to the Massachusetts Department of
Environmental Protection, a substantial number of borings were taken in
2008 to identify locations and depths of submerged tar.
Population expansion beginning in the early 1900s in the Hudson
River valley increased sewage output to the river, and sewage
decomposition produced several areas of inadequate oxygen (oxygen
blocks) in the river. Best documented was the oxygen block present in
the Albany pool, located north of the Atlantic sturgeon's spawning and
nursery habitat (Kahnle et al., 1998). Other oxygen blocks occurred at
certain times in the southern stretch of the river from the Tappan Zee
Bridge south through New York Harbor (Brosnan and O'Shea, 1997; Kahnle
et al., 1998). Improvements to sewage treatment eliminated the problem
near Albany by the late 1970s and near New York City by the middle to
late 1980s (Kahnle et al., 1998). PCB levels were high throughout much
of the river over the last several decades. In recent years, PCB
concentrations have declined to acceptable levels according to EPA
guidelines, but continual monitoring is needed to document the fate of
PCB contamination in the river (Sloan et al., 2005). The shortnose
sturgeon population in the Hudson River has increased significantly
(Bain et al., 2007) in the last several decades, suggesting that these
improvements in water quality have resulted in more suitable habitat
conditions for the species and, likely, better habitat conditions for
Atlantic sturgeon in the Hudson River as well.
Until recently, poor water quality has been a significant factor
affecting fish utilizing the upper tidal portion of the Delaware River
estuary. As recent as the early 1970s, dissolved oxygen levels between
Wilmington and Philadelphia were routinely below levels that could
support aquatic life from late spring to early fall (ASSRT, 2007).
Water quality has improved, however, to the extent that dissolved
oxygen levels have not dropped below the state's minimum standards at
any point during the year since 1990 (R. Green, Delaware DNREC, pers.
comm., 1998). As has been observed in other rivers (e.g., Penobscot and
Hudson Rivers), the biological status of shortnose sturgeon in the
Delaware River appears to be improving and suggests that water quality
has improved for Atlantic sturgeon that occur in the Delaware River as
well. For example, a portion of the Roebling-Trenton stretch of the
river is an EPA Superfund site due to the presence of the Roebling
Steel plant and contamination associated with plant operations; the EPA
has been considering ways to remove or cap the contamination in the
river caused by the plant operations.
The most recent (third edition) EPA Coastal Condition Report
identified that water quality was fair overall for waters south of Cape
Cod through Delaware (EPA, 2008). However, sampled sites in
Massachusetts and Rhode Island were generally scored as good while
waters from Connecticut to Delaware received fair and poor ratings
(EPA, 2008). In particular, the report noted that most of the Northeast
Coast sites with poor water quality ratings were concentrated in a few
estuarine systems, including New York/New Jersey Harbor, some
tributaries of the Delaware Bay, and the Delaware River (EPA, 2008).
With respect to the CB DPS, the period of Atlantic sturgeon
population decline and low abundance in the Chesapeake Bay corresponds
to a period of poor water quality caused by increased nutrient loading
and increased frequency of hypoxia (Officer et al., 1984; Mackiernan,
1987; Kemp et al., 1992; Cooper and Brush, 1993). The Bay is especially
vulnerable to the effects of nutrients due to its large surface area to
volume ratio, relatively low exchange rates, and strong vertical
stratification during the spring and summer months (ASSRT, 2007). The
EPAs Third Coastal Condition Report identified the water quality for
the Chesapeake Bay and immediate vicinity (to the Virginia--North
Carolina border) as fair to poor (EPA, 2008). In particular, the
western and northern tributaries of the Chesapeake Bay were rated as
poor (EPA, 2008). The extensive watersheds of this historically
unglaciated area funnel nutrients, sediment, and organic material into
secluded, poorly flushed estuaries that are more susceptible to
eutrophication (EPA, 2008).
Using a multivariable bioenergetics and survival model, Niklitschek
and Secor (2005) demonstrated that within the Chesapeake Bay, a
combination of low dissolved oxygen, water temperature, and salinity
restricts available Atlantic sturgeon habitat to 0-35 percent of the
Bay's modeled surface area during the summer. However, they further
demonstrated that achieving the EPA's new dissolved oxygen criteria for
the Chesapeake Bay would increase Atlantic sturgeon available habitat
by 13 percent per year (Niklitschek and Secor, 2005).
In addition to water quality, one of the limiting habitat
requirements for the CB DPS of Atlantic sturgeon may be the
availability of clean, hard substrate for attachment of demersal,
adhesive eggs (Bushnoe et al., 2005; C. Hager, VIMS, pers. comm.,
2005). In the Chesapeake Bay watershed, 18th and 19th century
agricultural clear cutting (Miller, 1986) contributed large sediment
loads that presumably have buried or reduced most sturgeon spawning
habitats (reviewed in Bushnoe et al., 2005).
Despite these water quality and sediment issues, Atlantic sturgeon
that were stocked in the Bay had very high survival rates, suggesting
that the sturgeon are able to adjust to conditions in the Bay or move
out of the Bay (e.g., into the rivers draining into the Bay) where
water quality is better. In addition, Atlantic sturgeon that originate
from other DPSs are often caught in the Bay and documented in the
reward program; indicating that the current water quality is not
preventing fish from moving into, and foraging in, the Bay.
Climate Change
Although the impacts of global climate change are uncertain,
researchers anticipate that the frequency and intensity of droughts and
floods will change across the nation (CBS, 2006). The latest report
from the Intergovernmental Panel on Climate Change (IPCC) predicts that
higher water temperatures and changes in extreme weather events,
including floods and droughts, are projected to affect water quality
and exacerbate many forms of water pollution, including sediments,
nutrients, dissolved organic carbon, pathogens, pesticides, and salt,
as well as thermal pollution, with possible negative impacts on
ecosystems, human health, and water system reliability and operating
costs. The resulting changes in water quality (temperature, salinity,
dissolved oxygen, contaminants, etc.) in rivers and coastal waters
inhabited by Atlantic sturgeon will likely affect those subpopulations.
Effects are expected to be more severe for those subpopulations that
occur at the southern extreme of the sturgeon's range, and in areas
that are already subject to poor water quality as a result of
eutrophication. In a simulation of the effects of water temperature on
available Atlantic sturgeon habitat, Niklitschek and Secor (2005) found
that a 1 [deg]C increase of water temperature in the Chesapeake
[[Page 61887]]
Bay would reduce available sturgeon habitat by 65 percent.
In summary, with the exception of the Merrimack River, dams do not
appear to limit Atlantic sturgeon access to spawning habitat. However,
it should be noted that accessibility does not equate to functionality.
Therefore, while historical spawning habitat may still be available,
some of the habitat may no longer be suitable spawning habitat. In
particular, water quality, while showing signs of improvement,
continues to rate only fair to poor in areas of the NYB DPS and CB DPS.
Dredging is known to have removed structures in the James River that
are typically associated with Atlantic sturgeon spawning habitat.
Nutrient loading and eutrophication of the Chesapeake Bay is expected
to get worse with temperature changes and other effects associated with
climate change. The SRT concluded that, cumulatively, dams, dredging,
turbines, and water quality posed a moderate risk to the GOM, NYB, and
CB DPSs. Of the threats to habitat that were considered, water quality
was of greatest concern in terms of its contribution to the risk of
endangerment for each DPS, overall. Based on the information provided
by the SRT as well as information on climate change that was not
considered by the SRT, and new information from the EPA on water
quality, we concur that water quality is the greatest of the threats
affecting the habitat or range of the GOM, NYB, and CB DPSs.
Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
As previously described, there is no directed commercial or
recreational fishery for Atlantic sturgeon in the U.S. Although capture
of Atlantic sturgeon on recreational fishing gear (e.g., rod and reel)
has occasionally occurred (ASSRT, 2007; P. Linthicum, pers. comm.), in
general, recreational fishing gear is not conducive to catching
Atlantic sturgeon.
Canadian fisheries for Atlantic sturgeon occur in the Saint
Lawrence and Saint John Rivers. Since Atlantic sturgeon of U.S. origin
are not expected to occur in areas of the Saint Lawrence and Saint John
where the fisheries occur, the Canadian commercial fishery for Atlantic
sturgeon is unlikely to capture sturgeon of U.S. origin.
The available information supports that the GOM, NYB, and CB DPSs
are not overutilized as a result of educational or scientific purposes.
There is no known use of Atlantic sturgeon for educational purposes
other than, possibly, limited display in commercial aquaria. Atlantic
sturgeon are the subject of scientific research in the wild and in
hatcheries, and may be incidentally caught during research for other
species such as shortnose sturgeon or assessment of commercial fish
stocks. The SRT (2007) reviewed recent and ongoing research studies
(from approximately 1988 to 2006) for Atlantic sturgeon in NMFS'
Northeast Region. Overall, hundreds of fish have been captured and
released and less than 10 mortalities have occurred (ASSRT, 2007).
Scientific research of ESA-listed species such as shortnose sturgeon
must comply with the permit requirements of the ESA, including measures
to minimize the likelihood of injury and death (e.g., short tow times
or soak times for collection gear, handling protocols). These measures
also minimize the likelihood of harm to Atlantic sturgeon when they are
also present. Trawl surveys to assess the status of commercial fish
stocks occur throughout the Northeast Region. The surveys typically use
short tow times that help to minimize mortality and injuries. Atlantic
sturgeon have been caught during such research operations, but there
have been no mortalities and all fish were released in good condition
(i.e., no apparent injuries) (B. Kramer, NEFSC, pers. comm., 2006).
While directed fisheries for Atlantic sturgeon are prohibited in
U.S. waters, Atlantic sturgeon are incidentally caught in other U.S.
fisheries. The SRT reviewed information on the commercial bycatch of
Atlantic sturgeon in Northeast waters from: (a) Estimates based on NMFS
sea sampling/observer data (Stein et al., 2004); (b) data collected as
part of Delaware's tagging studies (Shirey et al., 1997); and (c)
recapture data reported in the USFWS Atlantic Coast Sturgeon Tagging
Database (Eyler et al., 2004). Additional, new information on Atlantic
sturgeon bycatch in U.S. sink gillnet and otter trawl fisheries has
become available since completion of the SRT report (ASMFC TC, 2007).
At the request of the ASMFC, NMFS' Northeast Fisheries Science Center
estimated the total bycatch of Atlantic sturgeon in sink gillnet and
otter trawl gear based on observer data collected on a portion of
commercial fishing trips from Cape Hatteras, NC, through Maine for
2001-2006 (ASMFC TC, 2007). For sink gillnet gear, Atlantic sturgeon
bycatch ranged between 2,752 and 7,904 sturgeon annually, averaging
about 5,000 sturgeon per year (ASMFC TC, 2007). Atlantic sturgeon
bycatch in otter trawl gear similarly ranged between 2,167 and 7,210
sturgeon with an average of about 3,800 fish per year (ASMFC TC, 2007).
However, bycatch mortality was markedly different between the two gear
types. For sink gillnet fisheries, the estimated annual mortality
ranged from 352 to 1,286 Atlantic sturgeon, with an average mortality
of 649 sturgeon per year, or 13.8 percent of the annual Atlantic
sturgeon bycatch in sink gillnet gear (ASMFC TC, 2007). The total
number of Atlantic sturgeon killed in otter trawl gear could not be
estimated because of the low number of observed mortalities, indicating
a low mortality rate (ASMFC TC, 2007).
Approximately 15 to 19 percent of observed Atlantic sturgeon
bycatch in sink gillnet and otter trawl gear in 2001 to 2006 occurred
in coastal marine waters north of Chatham, MA (ASMFC TC, 2007).
However, since Atlantic sturgeon of different DPSs mix in the marine
environment, it is likely that sturgeon other than those belonging to
the GOM DPS were caught. Likewise, sturgeon that originate from the GOM
DPS are at risk of capture in sink gillnet and otter trawl gear
throughout the marine range of the species.
In addition to fisheries occurring in coastal waters, there are
limited gill net fisheries for menhaden, alewives, blueback herring,
sea herring, and mackerel in the estuarial complex of the Kennebec and
Androscoggin Rivers (ASSRT, 2007). State regulations prohibit the use
of purse, drag, and stop seines, and gill nets with greater than 87.5
mm stretched mesh (ASSRT, 2007). Fixed or anchored nets must be tended
continuously and hauled in and emptied every 2 hours (ASSRT, 2007).
There has been no reported or observed bycatch of Atlantic sturgeon in
these fisheries.
Approximately 39 to 55 percent of observed Atlantic sturgeon
bycatch in sink gillnet and otter trawl gear for 2001 to 2006 occurred
in coastal marine waters south of Chatham, MA and north of the
Delaware-Maryland border (ASMFC TC, 2007). As described above, since
Atlantic sturgeon of different DPSs mix in the marine environment, it
is likely that sturgeon other than those belonging to the NYB DPS were
caught in this area. Genetic analyses of tissue samples from captured
fish have shown that approximately 12 percent of the fish captured in
the New York Bight did not belong to the NYB DPS (T. King, unpublished,
2007). Likewise, sturgeon that originate from the NYB DPS are at risk
of capture in sink gillnet and otter trawl gear throughout the marine
range of the species. Genetic analyses of samples from Atlantic
sturgeon caught in Mid-Atlantic sink gillnet gear revealed that the
majority of fish
[[Page 61888]]
originated from the Hudson River (Waldman et al., 1996a; Secor, 2007).
Within the riverine range of the NYB DPS, the use of gillnet gear
in the Taunton River, MA, is restricted to nets of no more than 100
feet in length (2.54 m) and nets must be tended at all times (ASSRT,
2007). No overnight sets are allowed (K. Creighton, MA FEW, 2006;
ASSRT, 2007). Connecticut imposed a commercial harvest moratorium for
Atlantic sturgeon in 1997 (ASSRT, 2007). However, bycatch is known to
take place in the commercial shad fishery that operates in the lower
Connecticut River from April to June in large mesh (14 cm minimum
stretched mesh) gill nets (ASSRT, 2007). Likewise, New York implemented
a harvest moratorium for Atlantic sturgeon in 1996, but Atlantic
sturgeon bycatch occurs in a shad gill net fishery on the Hudson River
(ASSRT, 2007). However, New York State Department of Environmental
Conservation (NY DEC) recently proposed to close all American shad
fisheries in the Hudson River due to poor stock condition. Regulations
to close the fisheries for shad are expected to be implemented by
spring of 2010, and would effectively eliminate bycatch of Atlantic
sturgeon (K. Hattala, NY DEC, pers. comm., 2009).
Several fisheries using gillnet gear occur in the Delaware Bay,
including the striped bass, shad, white perch, Atlantic menhaden, and
weakfish fisheries (ASSRT, 2007). The majority of these operate in
March and April; bycatch mortality of Atlantic sturgeon during this
period is typically low (C. Shirey, DNREC, pers. comm., 2005). For
example, of the estimated 85 to 99 Atlantic sturgeon incidentally
captured in the Delaware Bay anchored gillnet fisheries for 2002
through 2003, none of the captures resulted in mortality (ASMFC
Atlantic Sturgeon Plan Review Team Report, 2004, 2005).
With respect to the CB DPS, the NEFSC analysis indicated that
coastal waters south of the Chesapeake Bay to Cape Hatteras, NC, had
the second highest number of observed Atlantic sturgeon captures in
sink gillnet gear for 2001-2006 (ASMFC TC, 2007). While it is likely
that the captured sturgeon originated from more than one DPS (Waldman
et al., 1996a; Secor, 2007), the data suggest that fisheries resulting
in high levels of Atlantic sturgeon bycatch occur in close proximity to
waters used by sturgeon belonging to the CB DPS. Interviews with local
fishermen in 2007 indicated that a gillnet fishery for dogfish was
known to incidentally catch sturgeon, and that fishery occurred off
Chincoteague Island, VA, where more than 30 dead Atlantic sturgeon were
found (Virginia Marine Police and Virginia Marine Resources Commission,
pers. comm.). The spiny dogfish fishery is managed under a Federal FMP
as well as an ASMFC interstate FMP. However, access to the fishery is
not limited, and directed effort in the fishery is expected to increase
as stock rebuilding objectives are met (ASMFC, 2009). A monkfish
fishery using large mesh gillnet gear also occurs in Federal waters off
Virginia as well as other Mid-Atlantic and New England states. Atlantic
sturgeon entanglements in gear used in the monkfish fishery have been
observed in Mid-Atlantic and New England waters (ASMFC, 2007).
In addition to fisheries occurring in marine waters, numerous
fisheries operate throughout the Chesapeake Bay (ASSRT, 2007). Juvenile
and subadult Atlantic sturgeon are routinely taken as bycatch
throughout the Chesapeake Bay in a variety of fishing gears (ASSRT,
2007). The mortality of Atlantic sturgeon bycatch in most of these
fisheries is unknown, although low rates of bycatch mortality were
reported for the striped bass gill net fishery and the shad fishery
within the Bay (Hager, 2006). Of the hundreds of sturgeon held for
examination in the Maryland and Virginia reward programs, only a few
fish were determined to be in poor physical condition, although it is
important to note that the program was designed to examine live
specimens for the reward to be granted (J. Skjeveland and A. Spells,
FWS, pers. comm., 1998).
In summary, overutilization of Atlantic sturgeon for commercial
purposes was likely the primary factor in the historical decline of the
GOM, NYB, and CB DPSs. A moratorium on the possession and retention of
Atlantic sturgeon for the past 10 years has effectively terminated any
directed harvest of Atlantic sturgeon. However, bycatch in Federal and
state regulated fisheries continues to occur. Atlantic sturgeon
populations can withstand only low rates of anthropogenic (e.g.,
fishing, bycatch) mortality (ASMFC TC, 2007). Kahnle et al. (2007)
estimated that sustainable fishing rates on adult Atlantic sturgeon are
5 percent per year, and sustainable fishing rates for sub-adults are
lower still (Boreman, 1997; ASMFC, 1998). Thus, the ASMFC TC (2007)
concluded that even small rates of bycatch mortality (<5 percent) on
sturgeon subpopulations could retard or curtail recovery. The best
available information supports that bycatch of Atlantic sturgeon in
Federal and state regulated fisheries acts as a significant threat on
the GOM, NYB, and CB DPSs because it results in direct mortality.
Fisheries known to incidentally catch Atlantic sturgeon occur
throughout the marine range of the species and in some riverine waters
as well. Therefore, adult and subadult age classes of each DPS are at
risk of injury or death resulting from entanglement and/or capture in
fishing gear wherever they occur.
Disease or Predation
Very little is known about natural predators of Atlantic sturgeon.
The presence of bony scutes is likely an effective adaptation for
minimizing predation of sturgeon greater than 25 mm TL (Gadomski and
Parsley, 2005; ASSRT, 2007). Documented predators of sturgeon species
(Acipenser sp.), in general, include sea lampreys, gar, striped bass,
common carp, northern pikeminnow, channel catfish, smallmouth bass,
walleye, fallfish, grey seal, and sea lion (Scott and Crossman, 1973;
Dadswell et al., 1984; Miller and Beckman, 1996; Kynard and Horgan,
2002; Gadomski and Parsley, 2005; Fernandes, 2006; Wurfel and Norman,
2006). Seal predation on shortnose sturgeon in the Penobscot River has
been documented (Fernandes, 2008). Seven shortnose sturgeon carcasses
found in the Kennebec River in August 2009 also bore wounds consistent
with seal predation (A. Lictenwalner, UME, pers. comm., 2009). Although
seal predation of Atlantic sturgeon has not been documented, Atlantic
sturgeon that are of comparable size to shortnose (e.g., subadult
Atlantic sturgeon) may also be susceptible to seal predation.
The presence of introduced flathead catfish has been confirmed in
the Delaware and Susquehanna River systems of the NYB and CB DPSs,
respectively (Horwitz et al., 2004; Brown et al., 2005). However, there
are no indications that the presence of flathead catfish in the Cape
Fear River, NC, and Altamaha River, GA (where flatheads have been
present for many years) is negatively impacting Atlantic sturgeon in
those rivers (ASSRT, 2007).
Disease organisms commonly occur among wild fish populations, but
under favorable environmental conditions, these organisms are not
expected to cause population-threatening epidemics. There are no known
diseases currently affecting any of the Atlantic sturgeon DPSs. A die-
off of sturgeon, 13 shortnose and two Atlantic sturgeon, was reported
for Sagadahoc Bay, ME, in July 2009, at the same time as a red tide
event for the region. The dinoflagellate associated with the red tide
event, Alexandrium fundyense, is known to produce saxitoxin, which can
cause paralytic shellfish poisoning when consumed in sufficient
quantity.
[[Page 61889]]
Stomach content analysis from the necropsied sturgeon revealed
saxitoxin levels of several hundred nanograms per gram (S. Fire, NOAA,
pers. comm., 2009). However, saxitoxin cannot be confirmed as the cause
of death of the sturgeon, given the lack of information on saxitoxin
presence in sturgeon tissues.
There is concern that non-indigenous sturgeon pathogens could be
introduced to wild Atlantic sturgeon, most likely through aquaculture
operations. Fungal infections and various types of bacteria have been
noted to have various effects on hatchery Atlantic sturgeon. Due to the
threat of impacts to wild populations, the ASMFC recommends requiring
any sturgeon aquaculture operation to be certified as disease-free,
thereby reducing the risk of the spread of disease from hatchery origin
fish. The aquarium industry is another possible source for transfer of
non-indigenous pathogens or non-indigenous species from one geographic
area to another, primarily through release of aquaria fish into public
waters. With millions of aquaria fish sold to individuals annually, it
is unlikely that such activity could ever be effectively regulated.
Definitive evidence that aquaria fish could be blamed for transmitting
a non-indigenous pathogen to wild fish (sturgeon) populations would be
very difficult to collect (J. Coll and J. Thoesen, USFWS, pers. comm.,
1998).
Disease and predation are not presently significant threats on the
GOM, NYB, or CB DPSs. While there is new evidence of seal predation on
shortnose sturgeon in the Penobscot and Kennebec Rivers of the GOM DPS
(Fernandes, 2008; A. Lictenwalner, UME, pers. comm., 2009), the number
of mortalities is believed to be low and thus, this is a localized
threat affecting a small number of fish. Likewise, we would expect that
any seal predation of Atlantic sturgeon, if it is occurring, would also
be low, given that Atlantic sturgeon spend less time in the rivers/
estuaries relative to shortnose sturgeon. There is also new evidence of
the presence of saxitoxin in sturgeon tissues. However, saxitoxin
presence cannot yet be associated as a cause of injury or mortality for
shortnose or Atlantic sturgeon.
Overall, the SRT concluded that there was a ``low risk'' that the
GOM, NYB, or CB DPS was likely to become endangered within the
foreseeable future as a result of disease or predation. Although there
is some new information regarding disease and predation of shortnose
sturgeon for waters within the range of the GOM DPS of Atlantic
sturgeon, the new information does not support an increased risk that
the GOM DPS of Atlantic sturgeon is likely to become endangered within
the foreseeable future as a result of disease or predation.
Inadequacy of Existing Regulatory Mechanisms
As a wide-ranging anadromous species, Atlantic sturgeon are subject
to numerous Federal (U.S. and Canadian), state and provincial, and
inter-jurisdictional laws, regulations, and agency activities. These
regulatory mechanisms are described in detail in the status review
report (see Section 3.4), and those that impact Atlantic sturgeon the
most are highlighted here.
Current regulatory mechanisms have effectively removed threats from
legal, directed harvest in the United States. As previously described,
the ASMFC manages Atlantic sturgeon through an interstate fisheries
management plan that was developed in 1990 (Taub, 1990). The moratorium
prohibiting directed catch of Atlantic sturgeon was developed as
Amendment 1 to the FMP. The Atlantic Coastal Fisheries Cooperative
Management Act (ACFCMA), authorized under the terms of the ASMFC
Compact, as amended (Pub. L. 103-206), provides the Secretary of
Commerce with the authority to implement regulations in the EEZ, in the
absence of an approved Magnuson-Stevens FMP, that are compatible to
ASMFC FMPs. It was under this authority that, in 1999, NMFS implemented
regulations that prohibit the retention and landing of Atlantic
sturgeon bycatch from federally regulated fisheries. NMFS has
discretion over the management of federally regulated fisheries and is
required to address bycatch for each federally regulated fishery.
Therefore, while there are currently no fishery specific regulations in
place that address Atlantic sturgeon bycatch, NMFS has the authority
and discretion to implement such measures, and has previously used its
authority to implement measures to reduce bycatch of protected species
in federally-regulated fisheries.
Some fisheries that occur within state waters are also known or
suspected of taking Atlantic sturgeon as bycatch. Maine's regulations
prohibit the use of purse, drag, and stop seines, and gill nets with
greater than 87.5 mm stretched mesh (ASSRT, 2007). Fixed or anchored
nets have to be tended continuously and hauled in and emptied every 2
hours (ASSRT, 2007). As described above, there has been no reported or
observed bycatch of Atlantic sturgeon in the limited gill net fisheries
for menhaden, alewives, blueback herring, sea herring, and mackerel in
the estuarial complex of the Kennebec and Androscoggin Rivers (ASSRT,
2007). However, the level of observer coverage or reporting effort is
unknown.
Atlantic sturgeon are also known to be taken as bycatch in the
Connecticut and Hudson River shad fisheries (ASSRT, 2007). Current
Connecticut regulations appear to be inadequate for addressing this
bycatch. In New York, however, the NY DEC closed all shad fisheries in
the Hudson River effective March 17, 2010 (NY DEC press release, March
17, 2010), thus, eliminating Atlantic sturgeon bycatch associated with
shad fisheries.
Gillnet fisheries for numerous fish species occur in the Chesapeake
Bay. Low rates of sturgeon bycatch mortality were reported for the
striped bass gill net fishery and the shad staked gill net fishery
(Hager, 2006; ASSRT, 2007), although estimates of bycatch in these
fisheries as well as other fisheries in the Bay are not available.
Since completion of the status review report, Virginia has closed the
directed fishery for American shad to allow rebuilding of the stock.
Virginia also has various time and gear restrictions for the use of
gillnet gear in its tidal waters, including prohibitions on the use of
staked or anchored gillnet gear in portions of the James and Rappannock
Rivers from April 1 through May 31 (VA MRC Summary of Regulations,
2009), that are likely to benefit Atlantic sturgeon by reducing the
likelihood of sturgeon bycatch. Similarly, regulations implemented by
NMFS (69 FR 24997, May 5, 2004; 71 FR 36024, June 23, 2006) to reduce
sea turtle interactions with pound net gear in the Bay and portions of
the surrounding rivers (e.g., James, York, and Rappahannock Rivers)
likely reduce the chance that Atlantic sturgeon will be caught in the
gear.
Due to existing state and Federal laws, water quality and other
habitat conditions have improved in many rivers (EPA, 2008). As
described above, dredging is a threat for the GOM, NYB, and CB DPSs of
Atlantic sturgeon. Currently, there are no specific regulations
requiring action(s) to reduce effects of dredging on Atlantic sturgeon.
However, NMFS has the authority and discretion to implement such
measures or require modification of dredging activities if Atlantic
sturgeon are listed under the ESA.
In summary, State and Federal agencies are actively employing a
variety of legal authorities to implement proactive restoration
activities for Atlantic sturgeon, and coordination of these efforts is
being furnished through the ASMFC. Most states within the
[[Page 61890]]
riverine and estuarine range of the GOM, NYB, and CB DPSs of Atlantic
sturgeon have regulations for their inshore gillnet fisheries that
reduce the likelihood of Atlantic sturgeon bycatch mortality in the
nets. NMFS has the authority and discretion to implement measures
necessary to reduce bycatch of Atlantic sturgeon in federally regulated
fisheries, and we expect that such measures would yield significant
benefits for Atlantic sturgeon. However, NMFS has not implemented any
bycatch reduction measures specifically for Atlantic sturgeon, and
existing bycatch reduction measures are inadequate for reducing bycatch
of Atlantic sturgeon in federally regulated fisheries. NMFS also has
the authority and discretion to require measures to reduce the effects
of in-water projects (e.g., dredging, tidal turbine projects) on ESA-
listed species. Such measures afford some benefit to Atlantic sturgeon
at times and in areas where the ESA-listed species is also present.
However, currently, NMFS does not have the authority or discretion to
require action to reduce the effects of in-water projects specifically
for Atlantic sturgeon. Therefore, Atlantic sturgeon are afforded no
protection from the effects of in-water projects if an ESA-listed
species is not present. There are no measures to reduce or minimize
vessel strikes (discussed in Other Natural or Manmade Factors Affecting
the Species' Continued Existence section below) of Atlantic sturgeon,
and we currently have limited authority and discretion by which to
regulate vessel activities in areas where Atlantic sturgeon occur.
Other Natural or Manmade Factors Affecting the Species Continued
Existence
The SRT considered several manmade factors that may affect Atlantic
sturgeon, including impingement and entrainment, vessel strikes, and
artificial propagation. Along the range of Atlantic sturgeon, most, if
not all, subpopulations are at risk of possible entrainment or
impingement in water withdrawal intakes for commercial uses, municipal
water supply facilities, and agricultural irrigation intakes. Based on
the behavior of captive larval Atlantic sturgeon (Kynard and Horgan,
2002), Atlantic sturgeon larvae may be able to avoid intake structures
in most cases, since migration is active and occurs near the bottom.
Effluence from power plant facilities also has the potential to affect
the Atlantic sturgeon DPSs. The release of heated water can benefit
sturgeon by providing a thermal refuge during the winter months, but
drastic changes in water temperature have the potential to cause
mortality. To date, there have been no known Atlantic sturgeon
mortalities as a result of effluent discharge of heated water.
Two surveys have been conducted that provide information on the
impacts of water withdrawal on Atlantic sturgeon originating from the
NYB DPS: (1) Hudson River Utility Surveys, and (2) Delaware River Salem
Power Plant survey. The Hudson River has six power plants located
between rkm 34-74, which overlap with known nursery grounds for
Atlantic sturgeon larvae and early juveniles located at rkm 43-100. Of
the six power plants located in this area, the Danskammer, Roseton,
Lovett, and Indian Point pose the greatest risk to Atlantic sturgeon,
as the Bowline Point power plant is located farther downriver and
withdraws water from a collection pond. Intensive surveys (24 hr/day, 4
to 7 days/week, and 10-12 weeks/year during the spring) conducted from
1972-1998 examining entrainment and impingement of fish species
reported only 8 entrained sturgeon (larvae) and 63 impinged shortnose
sturgeon (majority 200-700 mm) (Applied Science Associates, 1999).
Entrained sturgeon were documented only at the Danskammer Point Plant
where four shortnose larvae and four unidentified sturgeon yolk sac
larvae were observed during the spring in 1983 and 1984. Impingement of
sturgeon occurred most often at the Danskammer Point Plant, averaging
4.2-5.2 impinged fish per year, followed by Indian Point (1.5-2.3 fish/
year), Roseton (1.5-1.8 fish/year), Bowline Point (0-0.9 fish/year) and
Lovett Point (0 fish per year). During the period of 1989 to 1996, five
shortnose sturgeon were impinged (0.6/year) from the Roseton and
Danskammer plants. However, since 2000 when operational and physical
changes were made at these two plants, no impinged Atlantic or
shortnose sturgeon have been observed. Bowline Point and Lovett
reported zero impingements during this period. Sampling did not occur
at Indian Point after 1990 (Shortnose Sturgeon Status Review, in
draft).
The Salem Nuclear Generating Station located on the Delaware River
also has the potential to take sturgeon species via impingement or
entrainment. The trash racks at the Station are required to be
inspected every 2 hours from June 1 through October 15. The racks are
cleaned three times per week from May 1 to May 31 and October 16
through November 15, and are required to be cleaned daily from June 1
to October 15. Observations are made specifically for sturgeon species
during this time. During the remaining months, the trash racks are
inspected daily for debris load and cleaned as necessary. From 1978 to
2007, 18 shortnose sturgeon were collected at the cooling water system
intake. These fish were all juveniles greater than 400 mm TL. While
shortnose sturgeon have been observed at the intakes at the Station, no
Atlantic sturgeon have been observed.
Vessel strikes of Atlantic sturgeon have been documented in
particular areas. Atlantic sturgeon that occur in locations that
support large ports and have relatively narrow waterways seem to be
more prone to vessel strikes (e.g., Delaware and James Rivers). Twenty-
nine mortalities believed to be the result of vessel strikes were
documented in the Delaware River from 2004 to 2008 (Kahnle et al.,
2005; Murphy, 2006). At least 13 of these fish were large adults. Given
the time of year in which the fish were observed (predominantly May
through July, with two in August), it is likely that many of the adults
were migrating through the river to the spawning grounds. Based on the
external injuries observed, it is suspected that these strikes are from
ocean going vessels and not smaller boats, although at least one boater
reported hitting a large sturgeon with his small craft (C. Shirey,
DNREC, pers. comm., 2005). Recreational vessels are known to have
struck and killed shortnose sturgeon in the Kennebec River (G.
Wipplehauser, ME DMR, pers. comm., 2009). Therefore, it is likely that
Atlantic sturgeon can also suffer mortal injuries when struck by
recreational vessels.
In the James River, 11 Atlantic sturgeon were reported to have been
struck by vessels from 2005 through 2007 (A. Spells, FWS, pers. comm.,
2007). Of the six mortalities, two were mature males (approximate
lengths of 154-185 cm fork length (FL)); the other four carcasses were
in an advanced state of decay and could not be sexed. However, each of
the four was at least as large as the two mature males with one about
215 cm long and another appearing to have been much larger (only a
section of the larger fish was retrieved as it had been severed more
than once). The propeller marks present on the six fish examined
indicated that the wounds were inflicted by both large and small
vessels (A. Spells, FWS, pers. comm., 2007). One fish exceeding 154 cm
in length had been cut completely in two. Other sources suggest an even
higher rate of interaction with at least 16 Atlantic sturgeon
mortalities reported for a short reach of the James River during 2007-
2008 (Balazik, unpublished, in Richardson et al., 2009).
[[Page 61891]]
Artificial propagation of Atlantic sturgeon for use in restoration
of extirpated subpopulations or recovery of severely depleted wild
subpopulations has the potential to be both a threat to the species and
a tool for recovery. In 1991, the FWS Northeast Fisheries Center (NEFC)
in Lamar, Pennsylvania began a program to capture, transport, spawn,
and culture Atlantic sturgeon. This program was in response to
recommendations by the ASMFC in the Atlantic Sturgeon FMP (Taub, 1990)
and Special Report No. 22: Recommendation Concerning the Culture and
Stocking of Atlantic Sturgeon (ASMFC, 1992). The first successful spawn
at NEFC was achieved in 1993 using ripe Hudson River broodstock
captured by commercial fishermen. Approximately 175 individuals from
that year class and others are currently being maintained at NEFC for
use in a future broodstock. Subsequent propagation attempts in 1994,
1995, 1996, and 1998 were also successful with as many as 160,000 fry
being hatched in one year. The work at Lamar resulted in the
publication of the Culture Manual for the Atlantic sturgeon (Mohler,
2004). Since NEFC's first successful spawning in 1993, many requests
have been made for excess progeny both inside and outside of the
Department of the Interior. These requests were filled only under the
condition that a study plan be submitted to NEFC for review by the
Center Director and biologists. Study plans were required to include
provisions that escapement of cultured sturgeon into the wild would be
prevented except where experimental stockings were conducted consistent
with Federal and state regulations, and they should include a rigorous
evaluation component. Accordingly, over 29,000 artificially propagated
juvenile sturgeon have been shipped to 20 different organizations
including Federal and state agencies, universities, public aquaria, and
independent researchers.
In 1996, the Maryland Department of Natural Resources (MD DNR),
FWS, and the University of Maryland-Chesapeake Biological Laboratory
stocked the Nanticoke River with 3,300 hatchery-origin juveniles that
were obtained from the NEFC. The stocked fish demonstrated good growth
and survivability with a 14 percent recapture rate over several years
(MD DNR, 2007). MD DNR then began to rear sturgeon with the intention
of developing a captive spawning population for use in restoring
subpopulations in Maryland. The MD DNR program has been developed using
the culture and stocking guidance provided by ASMFC (2006).
Approximately 50 fish are currently maintained in the captive brood
population.
In summary, vessel strikes are a significant threat affecting the
NYB and CB DPSs. Currently, no state or Federal regulations exist to
reduce or minimize the likelihood of vessel strikes for Atlantic
sturgeon. Artificial propagation and impingement/entrainment of
Atlantic sturgeon have a low impact on the GOM, NYB, and CB DPSs and
are, therefore, minor threats to each of the three DPSs.
Current Protective Efforts
Current conservation efforts underway to protect and recover
Atlantic sturgeon must be evaluated according to the Policy for
Evaluation of Conservation Efforts (PECE) and pursuant to section
4(b)(1)(A) of the ESA. The PECE is designed to guide determinations on
whether any conservation efforts that have been recently adopted or
implemented, but not yet proven to be successful, will result in
recovering the species to the point at which listing is not warranted
or contribute to forming a basis for listing a species as threatened
rather than endangered (68 FR 15101; March 28, 2003). The purpose of
PECE is to ensure consistent and adequate evaluation of future or
recently implemented conservation efforts identified in conservation
agreements, conservation plans, management plans, and similar documents
when making listing decisions. The policy is expected to facilitate the
development by states and other entities of conservation efforts that
sufficiently improve a species' status so as to make listing the
species as threatened or endangered unnecessary.
The PECE established two basic criteria: (1) The certainty that the
conservation efforts will be implemented and, (2) the certainty that
the efforts will be effective. Satisfaction of the criteria for
implementation and effectiveness establishes a given protective effort
as a candidate for consideration, but does not mean that an effort will
ultimately change the risk assessment for the species. Overall, the
PECE analysis ascertains whether the formalized conservation effort
improves the status of the species at the time a listing determination
is made.
The SRT analyzed several conservation efforts potentially affecting
Atlantic sturgeon throughout its range. The 1998 Amendment to the ASMFC
Atlantic Sturgeon FMP strengthens conservation efforts by formalizing
the closure of the directed fishery, and by banning possession of
bycatch, eliminating any incentive to retain Atlantic sturgeon.
However, bycatch is known to occur in several fisheries (ASMFC TC,
2007), and it is widely accepted that bycatch is underreported (PECE
Implementation criterion 5). With respect to its effectiveness,
contrary to information available in 1998 when the Amendment was
approved, Atlantic sturgeon bycatch mortality is a primary threat
affecting the recovery of Atlantic sturgeon, despite actions taken by
the states and NMFS to prohibit directed fishing and retention of
Atlantic sturgeon. Therefore, there is considerable uncertainty that
the Atlantic Sturgeon FMP will be effective in meeting its conservation
goals (PECE Effectiveness criterion 1). In addition, there are limited
resources for assessing current abundance of spawning females for each
of the DPSs. Therefore, PECE effectiveness criterion 5 is not being
met.
For the reasons provided above, there is no certainty of
implementation and effectiveness of the intended ASMFC FMP conservation
effort for the GOM, NYB, or CB DPSs of Atlantic sturgeon.
Multi-State Conservation Program
Three states, Maine, New Hampshire, and Massachusetts, have applied
for and have received funding under a new Proactive Species
Conservation Program grant. The project, entitled ``Multi-State
Collaborative to Develop and Implement a Conservation Program for Three
Anadromous Fish Species of Concern in the Gulf of Maine,'' includes
proposed research on Atlantic sturgeon within the Kennebec River.
Specifically, project participants will: (1) Use acoustic biotelemetry
(deploy acoustic arrays) to identify essential Atlantic sturgeon
habitat in the Kennebec River/Androscoggin River complex; (2) conduct a
mark-and-recapture study using PIT tags to estimate subpopulation size
and external Carlin tags to investigate movements beyond the estuary;
(3) investigate non-traditional population estimation methods because
of spawning periodicity of adult sturgeon; and, (4) obtain tissue
samples for sturgeon to conduct genetic analysis and determine stock
structure.
The Atlantic sturgeon research component of the Multi-State
Conservation Program is expected to provide new information on the GOM
DPS of Atlantic sturgeon that could inform management decisions for
future conservation efforts. However, the program, including the
proposed research for Atlantic sturgeon, does not specifically describe
the threats to the Atlantic sturgeon subpopulations in
[[Page 61892]]
question, and does not address how those threats would be reduced or
eliminated (PECE Effectiveness criteria 1-6). Therefore, there is no
certainty of implementation and effectiveness of a formalized
conservation effort for the Penobscot River subpopulation of Atlantic
sturgeon, or for the GOM DPS to which it belongs, as a result of the
plan.
Penobscot River Restoration Project (PRRP)
The PRRP is the result of many years of negotiations between
Pennsylvania Power and Light (PPL), U.S. Department of the Interior
(e.g., FWS, Bureau of Indian Affairs, National Park Service), Penobscot
Indian Nation, the State of Maine (e.g., Maine State Planning Office,
Inland Fisheries and Wildlife, MDMR), and several non-governmental
organizations (NGOs; Atlantic Salmon Federation, American Rivers, Trout
Unlimited, Natural Resources Council of Maine, among others). If
implemented, the PRRP would lead to the removal of the two lowermost
mainstem dams on the Penobscot River (Veazie and Great Works) and would
decommission the Howland Dam and construct a nature-like fishway around
it. As a result, portions of historical habitat once available to
Atlantic sturgeon of the GOM DPS would be reopened. While the necessary
funding has been committed by the government and other private donors
to achieve the purchase of the dams, a significant amount of money
still must be acquired in order for the parties to exercise the option
to decommission and remove the Veazie and Great Works dams as well as
to construct a nature like fishway for the Howland Dam. Staffing,
funding level, funding source, and other resources necessary to fully
implement the PRRP are not identified at this time. Therefore,
currently, the PRRP does not satisfy criteria one and seven in the
certainty of implementation of the PECE. Permitting and regulatory
requirements are also uncertain at this stage because they are
contingent upon the ability of the parties to raise the full amount of
funds necessary, FERC approval of the Trust's permit to surrender the
dams, and completion of required environmental review. Thus, the PRRP
does not satisfy criterion four of the PECE, which requires that all
authorizations (e.g., permits, land owner permission) necessary to
implement the conservation effort are identified and that there is a
high certainty that the parties to the agreement will obtain all
necessary authorizations. Therefore, it is not possible to state at
this time with a high level of certainty that this project will be
fully implemented.
Hudson River Estuary Management Action Plan
A Hudson River Estuary Management Action Plan was adopted by the
NYDEC in May 1996. The goal of this Plan is to protect, restore, and
enhance the productivity and diversity of natural resources of the
Hudson River estuary to sustain a wide array of present and future
human benefits. Multiple projects have been initiated as a response to
this Plan. These include: (1) Coastal sampling; (2) juvenile Atlantic
sturgeon sonic tracking project; (3) broodstock sonic tagging and PIT
tagging to determine broodstock movements and spawning locations; and
(4) New York long-term juvenile abundance survey.
The research projects carried out under the Hudson River Estuary
Management Action Plan are expected to significantly increase our
knowledge of Atlantic sturgeon from the NYB DPS. Such information could
help to inform management decisions for future conservation efforts.
However, the Plan does not specifically describe the threats to the
Hudson River sturgeon subpopulation, and does not reduce or eliminate
those threats (PECE Effectiveness criteria 1-6). Therefore, there is no
certainty of implementation and effectiveness of a formalized
conservation effort for the Hudson River subpopulation of Atlantic
sturgeon, or for the NYB DPS to which it belongs, as a result of the
plan.
James River Atlantic Sturgeon Restoration Plan
In 2005, private and FWS partners began work to create a James
River Atlantic Sturgeon Restoration Plan. The plan outlines several
restoration goals to help preserve and recover the James River Atlantic
sturgeon subpopulation. These goals include: (1) Identify essential
habitats, assess subpopulation status, and refine life history
investigations in the James River; (2) protect the subpopulation of
James River Atlantic sturgeon and its habitat; (3) coordinate and
facilitate exchange of information on James River Atlantic sturgeon
conservation and restoration activities; and (4) implement the
restoration program. The plan also describes several milestones for
reaching these goals. Those of most interest to this review include:
(1) Identifying essential habitats and protecting them using regulatory
and/or incentive programs; (2) developing and implementing standardized
population sampling and monitoring programs; (3) developing population
models; (4) developing an experimental culture of James River Atlantic
sturgeon; (5) reducing or eliminating incidental mortality; (6)
identifying and eliminating known or potentially harmful chemical
contaminants that impede the recovery of James River sturgeon; (7)
maintaining genetic integrity and diversity of the wild and hatchery-
reared stocks; and (8) designating and funding a James River Atlantic
sturgeon restoration lead office.
Portions of the plan have already been implemented, including the
collection of YOY and adult tissue samples for genetic analysis;
electronic tracking of sturgeon to determine preferred habitat use and
spawning locations; collecting spine samples to establish age
distributions; and establishing a long-term YOY index survey (A.
Spells, FWS, pers. comm., 2007). All of these are expected to provide
new information on the CB DPS of Atlantic sturgeon that could inform
management decisions for future conservation efforts. However, the plan
has not been formally approved by regulatory agencies. Therefore, at
this time, it is uncertain whether the plan, including necessary
regulatory action, funding, and permitting (PECE Implementation
criterion 1, 2, 4, and 6-8) will be fully implemented. Information to
demonstrate the certainty that the conservation effort will be
effective is also lacking (PECE Effectiveness criterion 1-6).
Therefore, there is no certainty of implementation and effectiveness of
a formalized conservation effort for the James River subpopulation of
Atlantic sturgeon, or for the CB DPS of Atlantic sturgeon to which it
belongs, as a result of the plan.
Summary of Protective Efforts
Various agencies, groups, and individuals are carrying out a number
of efforts aimed at protecting and conserving Atlantic sturgeon
belonging to the GOM, NYB, and CB DPSs. These actions are directed at
reducing threats faced by Atlantic sturgeon and/or gaining additional
knowledge of specific Atlantic sturgeon subpopulations. Such actions
could contribute to the recovery of the GOM, NYB, and CB DPSs of
Atlantic sturgeon in the future. However, there is still considerable
uncertainty regarding the implementation and effectiveness of these
efforts, and the extent to which any would reduce the threats to the
GOM, NYB, or CB DPSs that are the cause of their (proposed) listing.
Therefore, we have determined that none of these protective efforts
currently contribute to making it unnecessary to list the GOM, NYB, or
CB DPSs of Atlantic sturgeon.
[[Page 61893]]
Finding for GOM DPS
As stated previously, the range of the GOM DPS is described as
watersheds from the Maine/Canadian border and extending southward to
include all associated watersheds draining into the Gulf of Maine as
far south as Chatham, MA, as well as all marine waters, including
coastal bays and estuaries, from the Bay of Fundy, Canada, to the Saint
Johns River, FL (Figure 3).
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There are no current abundance estimates for the GOM DPS of
Atlantic sturgeon. The Kennebec River is currently the only known
spawning river for the GOM DPS. The CPUE of subadult Atlantic sturgeon
in a multi-filament gillnet survey conducted on the Kennebec River was
considerably greater for the period of 1998-2000
[[Page 61894]]
(CPUE = 7.43) compared to the CPUE for the period 1977-1981 (CPUE =
0.30). The CPUE of adult Atlantic sturgeon showed a slight increase
over the same time period (1977-1981 CPUE = 0.12 versus 1998-2000 CPUE
= 0.21) (Squiers, 2004).
Evidence of Atlantic sturgeon spawning in other rivers of the GOM
DPS is not available. However, Atlantic sturgeon continue to use these
historical spawning rivers and may represent additional spawning groups
(ASSRT, 2007). There is also new evidence of Atlantic sturgeon presence
in rivers (e.g., the Saco River) where they have not been observed for
many years.
The majority of historical Atlantic sturgeon spawning habitat is
accessible in all but the Merrimack River of the GOM DPS. Whether
Atlantic sturgeon spawning habitat in the GOM DPS is fully functional
is difficult to quantify. In terms of threats to habitat, the SRT
identified water quality and dredging as threats. While measures do not
currently exist to minimize or reduce the impacts of dredging
specifically for Atlantic sturgeon, the regulatory mechanisms do exist
that would allow the development of such measures.
The SRT ranked bycatch as a primary threat for the GOM DPS of
Atlantic sturgeon since it poses an immediate risk of death for the
fish, and specific regulatory measures to remove or reduce Atlantic
sturgeon bycatch have not been implemented. Subadult and adult Atlantic
sturgeon of the GOM DPS may be incidentally caught in fisheries that
occur throughout their marine range. Many of the fisheries that result
in bycatch of Atlantic sturgeon, including the monkfish gillnet
fishery, are federally regulated through FMPs. NMFS is required to
reduce bycatch of federally managed fisheries. Therefore, while
measures to specifically reduce bycatch of Atlantic sturgeon are not in
place, the regulatory mechanisms that would allow the development of
such measures do exist.
The SRT considered the factors of section 4(a)(1) of the ESA and
concluded that there was a moderate risk (34-50 percent chance) that
the GOM DPS of Atlantic sturgeon would become endangered over the next
20 years. However, when considering this information as well as those
efforts being made to protect the species, the SRT concluded that there
were insufficient data to make a recommendation as to whether listing
was warranted.
Since completion of the status review report, we have received new
information on Atlantic sturgeon bycatch (ASMFC, 2007) and water
quality of the watersheds within the range of the GOM DPS (EPA, 2008).
While the new estimates of Atlantic sturgeon bycatch are comparable to
those considered by the SRT from Stein et al. (2004), new analyses
suggest that the level of bycatch mortality is not sustainable for the
GOM DPS in the long term (ASMFC, 2007).
With respect to water quality, despite the persistence of
contaminants and increasing land development, many rivers and
watersheds within the range of the GOM DPS have demonstrated
improvement in water quality (EPA, 2008). The most recent EPA Coastal
Condition Report identified water quality for coastal waters north of
Cape Cod as, generally, fair to good (EPA, 2008).
We further considered what effect low abundance may be having on
the GOM DPS. According to DeMaster et al. (2004), factors that tend to
decrease population growth rates at low levels of abundance result in a
process known as ``depensation.'' Depensation occurs, for example,
when: (1) It is more difficult for individuals to find mates at low
levels of abundance; (2) there is a loss of average fitness because the
gene pool tends to be smaller at low levels of abundance; or (3) the
species is more vulnerable to catastrophic events because a species is
likely to be composed of only one or a few populations at low levels of
abundance. When depensatory factors prevail, even with the elimination
of anthropogenic threats, the species tends toward extinction.
As described above, there is no abundance estimate for the GOM DPS.
Based on information available from Atlantic sturgeon subpopulations of
other DPSs, the SRT (2007) suggested that there may be less than 300
spawning adults per year for the Kennebec River subpopulation in the
GOM DPS. Presuming that the SRT's assumption is correct and that the
current total population abundance is low, we considered whether
depensation is currently occurring for the GOM DPS of Atlantic
sturgeon. We concluded that it is unlikely that the GOM DPS is
currently experiencing depensation given that Atlantic sturgeon of the
GOM DPS are being observed in increasing numbers (e.g., in the Kennebec
and the Merrimack River estuary) and in areas of the GOM DPS where they
have not been observed for many years (e.g., the Saco River). Such
observations are uncharacteristic of a subpopulation that is being
affected by depensation. In addition, we concluded that Atlantic
sturgeon are less susceptible to depensation in comparison to many
other species given certain life history characteristics. For example,
female Atlantic sturgeon produce a large number of eggs per spawning
year (400,000-4 million and potentially as many as 7-8 million; Smith
et al., 1982; Van Eenennaam et al. 1996; Van Eenennaam and Doroshov,
1998; Dadswell, 2006). Each reproductively active male Atlantic
sturgeon is capable of fertilizing the eggs of multiple females within
a spawning year and, as a result of natal homing, spawning adults are
cued to areas where they can expect to find ``mates.'' These
characteristics help to ensure that successful reproduction can still
occur even at low levels of abundance. Furthermore, Atlantic sturgeon
of a single DPS are temporally and spatially separated depending on age
class and reproductive condition. For example, males spawn every 1 to 2
years and females every 3 to 5 years. Spawning occurs over weeks with
reproductively active females making relatively short spawning runs,
thus minimizing their exposure to catastrophic events that might occur
in the spawning rivers. Subadults and non-spawning adults range across
a wide area of the marine environment while YOY and juveniles occur in
the estuaries of their natal river. These characteristic range and
habitat patterns reduce the likelihood that a single catastrophic event
(e.g., a flood, drought, red-tide event) would kill or injure a
sufficient number of sturgeon across a single or all age classes such
that the DPS would become extinct.
We also considered whether the spatial structure of the GOM DPS has
been degraded to the extent that the viability of the population is
threatened. According to the NMFS report, ``Viable Salmonid Populations
and the Recovery of Evolutionarily Significant Units'' (2000), ``a
population's spatial structure is made up of both the geographic
distribution of individuals in the population and the processes that
generate that distribution. A population's spatial structure depends
fundamentally on habitat quality, spatial configuration, and dynamics
as well as the dispersal characteristics of individuals in the
population. As one example of how a degraded spatial structure can
threaten the viability of a population, consider a population divided
into subpopulations. A population with a high subpopulation extinction
rate can persist only if new subpopulations are founded at a rate equal
to the rate at which subpopulations naturally go extinct. If human
activity interferes with the
[[Page 61895]]
formation of new subpopulations by restricting straying patterns or
destroying habitat patches suitable for colonization, the population
will ultimately go extinct as subpopulations blink out one by one.
However, there will be a time lag between the disruption of spatial
processes and reductions in the abundance or productivity of the
population because abundance will not necessarily decline until
subpopulations start going extinct.'' Based on the best available
information, human activity is not restricting straying patterns for
Atlantic sturgeon belonging to the GOM DPS or destroying patches
suitable for colonization. To the contrary, Atlantic sturgeon of the
GOM DPS are being observed in increasing numbers (e.g., in the
Merrimack River estuary) and in areas (e.g., the Saco River) where they
have not been observed for many years.
In summary, based on the information contained in the status review
report and new information on bycatch of Atlantic sturgeon as well as
water quality for the watersheds of the GOM DPS, we concur with the SRT
that bycatch, water quality, and dredging are the threats affecting the
GOM DPS of Atlantic sturgeon. The SRT determined that there was a
moderate risk (34-50 percent chance) that the GOM DPS of Atlantic
sturgeon would become endangered over the next 20 years. Since
completion of the status review report, fish have been documented in
rivers where they were previously not reported to occur or where they
were suspected of having been extirpated. The new information on water
quality (EPA, 2008) indicates that water quality has improved. The new
information on bycatch (ASMFC TC, 2007), however, supports that bycatch
is having a greater impact on Atlantic sturgeon than that considered by
the SRT. Age to maturity for Atlantic sturgeon of the GOM DPS is
unknown. However, age at maturity is 11 to 21 years for Atlantic
sturgeon originating from the Hudson River (Young et al., 1998), and 22
to 34 years for Atlantic sturgeon that originate from the Saint
Lawrence River (Scott and Crossman, 1973). Age at maturity for Atlantic
sturgeon of the GOM DPS likely fall within these values given that
Atlantic sturgeon subpopulations exhibit clinal variation with faster
growth and earlier age to maturity for those that originate from more
southern waters, and slower growth and later age to maturity for those
that originate from more northern waters. Since there is only one
(known) spawning group for the GOM DPS, loss of the spawning group
would result in extinction of the DPS.
Given these considerations, including the original determination by
the SRT, the best available information indicates the DPS is likely to
become an endangered species within the foreseeable future (i.e., a
greater than 50 percent chance of becoming endangered over the next 20
years) throughout all or a significant portion of its range due to
bycatch, water quality, and dredging. There are several indications of
potential for improvement in the status of the DPS, including the
following: There have been and continue to be improvements in water
quality; regulatory mechanisms to address bycatch exist and could be
effectively implemented to reduce associated mortalities; the effects
of dredging have been and continue to be addressed for shortnose
sturgeon and, therefore, provide indirect benefits for Atlantic
sturgeon utilizing the same areas; and there are some indications of
increased spatial distribution of Atlantic sturgeon in some areas of
the DPS (e.g., use of the Saco River and increased use of the Merrimack
River estuary). However, given the on-going threats to the GOM DPS, we
conclude that listing as threatened is warranted for the GOM DPS of
Atlantic sturgeon.
Finding for NYB DPS
As stated previously, the range of the NYB DPS is described as
watersheds that drain into coastal waters, including Long Island Sound,
the New York Bight, and Delaware Bay, from Chatham, MA, to the
Delaware-Maryland border on Fenwick Island, as well as all marine
waters, including coastal bays and estuaries, from the Bay of Fundy,
Canada, to the Saint Johns River, FL (Figure 4).
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The only abundance estimate for Atlantic sturgeon belonging to the
NYB DPS is 870 spawning adults per year for the Hudson River
subpopulation (Kahnle et al., 2007). However, the estimate is based on
data collected from 1985-1995 and may underestimate current conditions
(Kahnle et al., 2007). Data collected from the Hudson River cannot be
used to estimate the total number of adults in the subpopulation since
mature Atlantic sturgeon may not spawn every year (Vladykov and
Greeley, 1963; Smith, 1985; Van Eenennaam et al., 1996; Stevenson and
Secor, 1999; Collins et al., 2000; Caron et al., 2002), and it is
unclear to what extent mature fish in a non-spawning condition occur on
the spawning grounds.
In addition to the Hudson River, Atlantic sturgeon are known to
spawn in the Delaware River. Since 1991, more than 2,000 Atlantic
sturgeon have been captured and tagged (DNREC, 2009) in the Delaware
River. Evidence of Atlantic sturgeon spawning in the Taunton and
Connecticut rivers of the NYB DPS is not available. However, Atlantic
sturgeon continue to use these rivers (ASSRT, 2007).
The majority of historical Atlantic sturgeon spawning habitat for
the NYB DPS is accessible. Whether Atlantic sturgeon spawning habitat
in the NYB DPS is fully functional is difficult to quantify. In terms
of threats to habitat, the SRT identified water quality and dredging,
and in terms of threats affecting the Delaware River subpopulation of
the DPS directly, the SRT identified vessel strikes. While
[[Page 61897]]
contaminants persist, the SRT noted several studies and reports
indicating improvements in water quality within the Hudson, Delaware,
Taunton, and Connecticut Rivers. Measures do not currently exist to
remove or reduce the impacts of dredging and vessel strikes for
Atlantic sturgeon. However, the regulatory mechanisms do exist that
would allow the development of such measures.
The SRT ranked bycatch as the primary threat for the NYB DPS of
Atlantic sturgeon since it poses an immediate risk of death for the
fish, and specific regulatory measures to remove or reduce Atlantic
sturgeon bycatch have not been implemented. Subadult and adult Atlantic
sturgeon of the NYB DPS may be incidentally caught in fisheries that
occur throughout their marine range. Many of the fisheries that result
in bycatch of Atlantic sturgeon, including the monkfish gillnet
fishery, are federally regulated through FMPs. NMFS is required to
reduce bycatch of federally managed fisheries. Therefore, while
measures to specifically reduce bycatch of Atlantic sturgeon are not in
place, the regulatory mechanisms that would allow the development of
such measures do exist.
The SRT considered the factors in section 4(a)(1) of the ESA and
concluded that there was a moderate (34-50 percent chance) to
moderately high risk (greater than 50 percent chance) that the NYB DPS
would become endangered over the next 20 years.
Since completion of the status review report, we have received new
information on Atlantic sturgeon bycatch (ASMFC, 2007) and water
quality for the watersheds within the NYB DPS (EPA, 2008). While the
new estimates of Atlantic sturgeon bycatch are comparable to those
considered by the SRT from Stein et al. (2004), new analyses suggest
that the level of bycatch mortality is not sustainable for the NYB DPS
in the long term (ASMFC, 2007). With respect to water quality, the most
recent EPA Coastal Condition Report identified that coastal water
quality was fair overall for waters south of Cape Cod through Delaware
(EPA, 2008). However, sampled sites in Massachusetts and Rhode Island
were generally scored as good while waters from Connecticut to Delaware
received fair and poor ratings (EPA, 2008). In particular, the report
noted that most of the Northeast Coast sites that were rated as poor
for water quality were concentrated in a few estuarine systems,
including New York/New Jersey Harbor, some tributaries of the Delaware
Bay, and the Delaware River (EPA, 2008).
Significant increases in abundance and distribution of shortnose
sturgeon within the Hudson and Delaware Rivers suggest that
improvements in water quality have resulted in benefits to the species.
Available evidence further suggests that existing water quality in
these rivers and surrounding estuaries is not impeding reproduction of
shortnose sturgeon that occur there.
We further considered what effect low abundance may be having on
the NYB DPS, and whether the NYB DPS is currently experiencing
depensation. As described above, the estimate of 870 spawning adults
per year for the Hudson River subpopulation is based on data collected
from 1985-1995 (Kahnle et al., 2007). The SRT (2007) suggested that
there may be less than 300 spawning adults per year for the Delaware
subpopulation of the NYB DPS. We concluded that it is unlikely that the
Hudson River subpopulation of the NYB DPS is currently experiencing
depensation given the available population estimate which suggests an
adult spawning population of close to 1,000 sturgeon. We were unable to
make a conclusion as to whether depensation is likely occurring for the
Delaware subpopulation of the NYB DPS. Evidence of age-0 fish in the
Delaware River in 2009 indicates that spawning continues to occur in
that river. Ongoing studies may help to elucidate the abundance and/or
trend in abundance of this subpopulation. However, that information is
not yet available. As described in the finding for the GOM DPS, we have
concluded that certain Atlantic sturgeon life history characteristics
help to reduce the likelihood that depensation will occur. Thus, we
expect that depensation for Atlantic sturgeon would occur at a lower
level of abundance in comparison to a species that did not share these
characteristics.
We also considered whether the spatial structure of the NYB DPS has
been degraded to the extent that the viability of the population is
threatened. Based on the best available information, human activity is
not restricting straying patterns for Atlantic sturgeon belonging to
the Hudson River subpopulation of the NYB DPS. It is unclear, however,
to what extent human activity is restricting straying patterns of
sturgeon belonging to the Delaware subpopulation of the NYB DPS, given
the very limited information on abundance and the known threats
affecting this subpopulation (i.e., bycatch, water quality, dredging
and vessel strikes).
In summary, based on the information contained in the status review
report and new information on bycatch of Atlantic sturgeon and water
quality for the watersheds of the NYB DPS, we concur with the SRT that
bycatch, water quality, dredging, and vessel strikes act as significant
threats affecting the NYB DPS of Atlantic sturgeon. The SRT determined
that there was a moderate (34-50 percent chance) to moderately high
risk (greater than 50 percent chance) that the NYB DPS would become
endangered over the next 20 years. The new information on water quality
for the area covered by the NYB DPS (EPA, 2008) is similar to that
considered by the SRT for the status report. The new information on
bycatch (ASMFC TC, 2007), however, supports that bycatch is having a
greater impact on Atlantic sturgeon than that considered by the SRT.
Additionally, since completion of the status review report, a dredging
project to deepen the Delaware shipping channel in an area where
Atlantic sturgeon is suspected to occur has been proposed and is in the
process of attaining necessary approvals. Age to maturity for NYB DPS
Atlantic sturgeon is 11 to 21 years (Young et al., 1998; DNREC, 2009).
Given that there are two spawning groups for the NYB DPS, loss of one
spawning group will not result in the immediate extinction of the NYB
DPS. Nevertheless, the loss of either spawning group would result in
loss of spatial structure for the DPS as well as numbers of fish to
support spawning. Therefore, both spawning groups are essential to the
DPS.
Given these considerations, we find that the best available
information does support that the NYB DPS is in danger of extinction
throughout all or a significant portion of its range. There are several
indications of potential for improvement in the status of the DPS,
including the following: Regulatory mechanisms to address bycatch exist
and could be effectively implemented to reduce associated mortalities;
and the effects of dredging have been and continue to be addressed for
shortnose sturgeon and, therefore, provide indirect benefits for
Atlantic sturgeon where these species co-occur. However, given the
ongoing threats to the NYB DPS, we conclude that listing as endangered
is warranted for the NYB DPS of Atlantic sturgeon.
Finding for CB DPS
As stated previously, the range of the CB DPS is described as
watersheds that drain into the Chesapeake Bay and into coastal waters
from the Delaware-Maryland border on Fenwick Island to Cape Henry, VA,
as well as all marine waters, including coastal bays and estuaries,
from the Bay of Fundy,
[[Page 61898]]
Canada, to the Saint Johns River, FL (Figure 5).
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There are no current abundance estimates for the CB DPS. As
previously stated, the FWS has been funding the Maryland Reward Program
since 1996; this program has resulted in the documentation of over
1,133 wild Atlantic sturgeon. Virginia also instituted an Atlantic
sturgeon reward program in the Chesapeake Bay in 1997 and 1998 (Spells,
2007). This reward program documented and measured 295 Atlantic
sturgeon. However, since sturgeon from multiple DPSs occur in the
Chesapeake Bay, it is unlikely that all of the sturgeon captured
originated from the CB DPS.
Atlantic sturgeon of the CB DPS are known to spawn in the James
River. Clear evidence of Atlantic sturgeon spawning in other rivers of
the CB DPS is not available. However, Atlantic sturgeon continue to use
these rivers,
[[Page 61899]]
and may represent additional spawning groups (ASSRT, 2007). In
particular, commercial fishers have regularly reported observations of
YOY or age-1 juveniles in the York River over the past few years (K.
Place, Commercial Fisherman, pers. comm., 2006). Analyses of samples
collected from Atlantic sturgeon juveniles in the James and York Rivers
also demonstrated genetic differences between the sampled groups. The
observations and genetic results suggest that spawning may be occurring
in the York River.
The majority of historical Atlantic sturgeon spawning habitat for
the CB DPS is accessible. Although dams are present, most are located
upriver of where spawning is expected to have historically occurred.
Whether Atlantic sturgeon spawning habitat in the CB DPS is fully
functional is difficult to quantify. In terms of threats to habitat,
the SRT identified water quality and dredging, and in terms of direct
threats to the CB DPS, the SRT identified vessel strikes. Initiatives
have been called for to address the condition of the Chesapeake Bay
(Executive Order, May 12, 2009; NOAA's Chesapeake Bay Protection and
Restoration Final Strategy, 2010). Niklitschek and Secor (2005)
demonstrated that achieving the EPA`s dissolved oxygen criteria for the
Chesapeake Bay would increase Atlantic sturgeon available habitat by 13
percent per year (Niklitschek and Secor, 2005). Measures do not
currently exist to remove or reduce the impacts of dredging and vessel
strikes specifically for Atlantic sturgeon. However, the regulatory
mechanisms that would allow the development of such measures do exist.
The SRT ranked bycatch as a primary threat for the CB DPS of
Atlantic sturgeon because it poses an immediate risk of death for the
fish, and specific regulatory measures to remove or reduce Atlantic
sturgeon bycatch have not been implemented. Subadult and adult Atlantic
sturgeon of the CB DPS may be incidentally caught in fisheries that
occur throughout their marine range. Many of the fisheries that result
in bycatch of Atlantic sturgeon, including the monkfish gillnet
fishery, are federally regulated through FMPs. NMFS is required to
reduce bycatch in federally managed fisheries. Therefore, while
measures to specifically reduce bycatch of Atlantic sturgeon are not in
place, the regulatory mechanisms that would allow the development of
such measures do exist.
The SRT considered the factors in section 4(a)(1) of the ESA and
concluded that there was a moderately high risk (greater than 50
percent chance) that the CB DPS would become endangered over the next
20 years.
Since completion of the status review report, we have received new
information on the bycatch of Atlantics sturgeon (ASMFC, 2007) and
water quality of the watersheds within the CB DPS (EPA, 2008). While
the new estimates of Atlantic sturgeon bycatch are comparable to those
considered by the SRT from Stein et al. (2004), new analyses suggest
that the level of bycatch mortality is not sustainable for the CB DPS
in the long term (ASMFC, 2007). With respect to water quality, the most
recent EPA Coastal Condition Report identified water quality as fair to
poor for the Chesapeake Bay and immediate vicinity (to the Virginia-
North Carolina border) (EPA, 2008). In particular, the western and
northern tributaries of the Chesapeake Bay were rated as poor (EPA,
2008). The Bay is especially vulnerable to the effects of nutrients due
to its large surface area to volume ratio, relatively low exchange
rates, and strong vertical stratification during the spring and summer
months (ASSRT, 2007). The extensive watersheds of this historically
unglaciated area funnel nutrients, sediment, and organic material into
secluded, poorly flushed estuaries that are more susceptible to
eutrophication (EPA, 2008).
We further considered what effect low abundance may be having on
the CB DPS, and whether the CB DPS is currently experiencing
depensation. As described above, there is no abundance estimate for the
CB DPS. Based on information available from Atlantic sturgeon
subpopulations of other DPSs, the SRT (2007) suggested that there may
be less than 300 spawning adults per year for the CB DPS. Presuming
that the SRT's assumption is correct and assuming that the current
total population abundance is low, we considered whether the CB DPS is
currently experiencing depensation. We concluded that it is unlikely
that the CB DPS is currently experiencing depensation, given that
increasing numbers of Atlantic sturgeon belonging to the CB DPS are
being observed (Garman and Balazik, unpub. data in Richardson et al.,
2009). Such observations are uncharacteristic of a population that is
experiencing depensation. In addition, as described in the finding for
the GOM DPS, we have concluded that certain Atlantic sturgeon life
history characteristics help to reduce the likelihood that depensation
will occur. Thus, we expect that depensation for Atlantic sturgeon
would occur at a lower level of abundance in comparison to species that
did not share these characteristics.
We also considered whether the spatial structure of the CB DPS has
been degraded to the extent that the viability of the population is
threatened. Observations of increased numbers of juvenile and adult
Atlantic sturgeon suggest that human activity is not significantly
restricting straying patterns for Atlantic sturgeon belonging to the CB
DPS. However, the evidence is not conclusive, given the very limited
information on abundance and distribution of Atlantic sturgeon in the
tributaries to the Bay, and the known threats affecting the DPS (i.e.,
bycatch, water quality, dredging, and vessel strikes).
In summary, based on the information contained in the status review
report and new information on bycatch of Atlantic sturgeon and water
quality for the watersheds of the CB DPS, we concur with the SRT that
bycatch, water quality, dredging, and vessel strikes act as significant
threats affecting the CB DPS of Atlantic sturgeon. The SRT determined
that there was a moderately high risk (greater than 50 percent chance)
that the CB DPS would become endangered over the next 20 years. The new
information on water quality for the area covered by the CB DPS (EPA,
2008) is similar to that considered by the SRT for the status review
report. In addition, the new information on bycatch (ASMFC TC, 2007)
supports that bycatch is having a greater impact on Atlantic sturgeon
than that considered by the SRT. Age at maturity for Atlantic sturgeon
originating from the Chesapeake Bay DPS is unknown. However, age at
maturity is 5 to 19 years for Atlantic sturgeon originating from South
Carolina rivers (Smith et al., 1982), and 11 to 21 years for Atlantic
sturgeon originating from the Hudson River (Young et al., 1998). Age at
maturity for Atlantic sturgeon of the CB DPS likely fall within these
values given that Atlantic sturgeon subpopulations exhibit clinal
variation with faster growth and earlier age to maturity for those that
originate from more southern waters, and slower growth and later age to
maturity for those that originate from more northern waters. Since
there is only one (known) spawning river for the CB DPS, loss of that
spawning group would result in extinction of the DPS.
Given these considerations, we find that the best available
information does support that the CB DPS is in danger of extinction
throughout all or a significant portion of its range. There are several
indications of potential for improvement in the status of the DPS,
including the following: Regulatory
[[Page 61900]]
mechanisms to address bycatch exist and could be effectively
implemented to reduce associated mortalities; and the effects of
dredging have been and continue to be addressed for shortnose sturgeon
and, therefore, provide indirect benefits for Atlantic sturgeon where
these species co-occur. However, given the ongoing threats to the CB
DPS, we conclude that listing as endangered is warranted for the CB DPS
of Atlantic sturgeon.
Role of 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, the Atlantic sturgeon status review report was
peer reviewed by six experts in the field, with their substantive
comments incorporated in the final status review report.
On July 1, 1994, the NMFS and USFWS published a series of policies
regarding listings under the ESA, including a policy for peer review of
scientific data (59 FR 34270). The intent of the peer review policy is
to ensure that listings are based on the best scientific and commercial
data available. Prior to a final listing, NMFS will solicit the expert
opinions of three qualified specialists selected from the academic and
scientific community, Federal and State agencies, and the private
sector on listing recommendations to ensure the best biological and
commercial information is being used in the decisionmaking process, as
well as to ensure that reviews by recognized experts are incorporated
into the review process of rulemakings developed in accordance with the
requirements of the ESA.
Effects of Listing
Conservation measures provided for species listed as endangered or
threatened under the ESA include recovery actions (16 U.S.C. 1533(f)),
critical habitat designations, Federal agency consultation requirements
(16 U.S.C. 1536), and prohibitions on taking (16 U.S.C. 1538).
Recognition of the species' plight through listing promotes
conservation actions by Federal and state agencies, private groups, and
individuals. Should the proposed listings be made final, a recovery
program would be implemented, and critical habitat may be designated.
Federal, state, and the private sectors will need to cooperate to
conserve listed Atlantic sturgeon and the ecosystems upon which they
depend.
Critical habitat is defined in section 3 of the ESA (16 U.S.C.
1532(3)) as: (1) The specific areas within the geographical area
occupied by a species, at the time it is listed in accordance with the
ESA, on which are found those physical or biological features (a)
essential to the conservation of the species and (b) that may require
special management considerations or protection; and (2) specific areas
outside the geographical area occupied by a species at the time it is
listed upon a determination that such areas are essential for the
conservation of the species. ``Conservation'' means the use of all
methods and procedures needed to bring the species to the point at
which listing under the ESA is no longer necessary. Section 4(a)(3)(a)
of the ESA (16 U.S.C. 1533(a)(3)(A)) requires that, to the extent
prudent and determinable, critical habitat be designated concurrently
with the listing of a species. If we determine that it is prudent and
determinable, we will publish a proposed designation of critical
habitat for Atlantic sturgeon in a separate rule. Public input on
features and areas that may meet the definition of critical habitat for
the Gulf of Maine, New York Bight, and Chesapeake Bay DPSs is invited.
Identifying the DPS(s) Potentially Affected by an Action During Section
7 Consultation
The GOM, NYB, and CB DPSs are distinguished based on genetic data
and spawning locations. However, extensive mixing of the populations
occurs in coastal waters. Therefore, the distributions of the DPSs
outside of natal waters generally overlap with one another, and with
fish from Southeast river populations. This presents a challenge in
conducting ESA section 7 consultations because fish from any DPS could
potentially be affected by a proposed project. Project location alone
will likely not inform the section 7 biologist as to which populations
to consider in the analysis of a project's potential direct and
indirect effects on Atlantic sturgeon and their habitat. This will be
especially problematic for projects where take could occur because it
is critical to know which Atlantic sturgeon population(s) to include in
the jeopardy analysis. One conservative, but potentially cumbersome,
method would be to analyze the total anticipated take from a proposed
project as if all Atlantic sturgeon came from a single DPS and repeat
the jeopardy analysis for each DPS the taken individuals could have
come from. However, recently funded research may shed some light on the
composition of mixed stocks of Atlantic sturgeon, relative to their
rivers of origin, in locations along the East Coast. The specific
purpose of the study is to evaluate the vulnerability to coastal
bycatch of Hudson River Atlantic sturgeon, thought to be the largest
stock contributing to coastal aggregations from the Bay of Fundy to
Georgia. However, the mixed stock analysis will also allow NMFS to
better estimate a project's effects on different components of a mixed
stock of Atlantic sturgeon in coastal waters or estuaries other than
where they were spawned. Results from the study are expected in
February 2011. Genetic mixed stock analysis, such as proposed in this
study, requires a high degree of resolution among stocks contributing
to mixed aggregations and characterization of most potential
contributory stocks. Fortunately, almost all extant populations, at
least those with reasonable population sizes, have been characterized
in previous genetic studies, though some additional populations will be
characterized in this study. Genetic testing of mixed stocks will be
conducted in eight coastal locales in both the Northeast and Southeast
Regions. Coastal fisheries and sites were selected based on sample
availabilities, bycatch concerns, and specific biological questions
(i.e., real uncertainty as to stock origins of the coastal
aggregation). We are specifically seeking public input on the mixing of
fish from different DPSs in parts of their ranges, particularly in the
marine environment.
Identification of Those Activities That Would Constitute a Violation of
Section 9 of the ESA
On July 1, 1994, we and USFWS published a policy to identify, to
the maximum extent possible, those activities that would or would not
constitute a violation of section 9 of the ESA (59 FR 34272). The
intent of this policy is to increase public awareness of the effect of
this listing on proposed and ongoing activities within the species'
range. We will identify, to the extent known at the time of the final
rule, specific activities that will not be considered likely to result
in violation of section 9, as well as activities that will be
considered likely to result in violation. Activities that we believe
[[Page 61901]]
could result in violation of section 9 prohibitions against ``take'' of
the Atlantic sturgeon in the NYB and CB DPSs include, but are not
limited to, the following: (1) Bycatch associated with commercial and
recreational fisheries; (2) poaching of individuals for meat or caviar;
(3) marine vessel strikes; (4) destruction of riverine, estuarine, and
marine habitat through such activities as agricultural and urban
development, commercial activities, diversion of water for hydropower
and public consumption, and dredge and fill operations; (5) impingement
and entrainment in water control structures; (6) unauthorized
collecting or handling of the species (permits to conduct these
activities are available for purposes of scientific research or to
enhance the propagation or survival of the DPSs); (7) releasing a
captive Atlantic sturgeon into the wild; and (8) harming captive
Atlantic sturgeon by, among other things, injuring or killing them
through veterinary care, research, or breeding activities outside the
bounds of normal animal husbandry practices. We intend to undergo a
rulemaking process under section 4(d) to issue protective regulations
for the GOM DPS, which is being proposed as threatened under the ESA,
and it is likely that these same activities would result in violation
of take prohibitions that we may extend to the GOM DPS in such a
section 4(d) rule.
We believe that, based on the best available information, the
following actions will not result in a violation of section 9: (1)
Possession of Atlantic sturgeon acquired lawfully by permit issued by
NMFS pursuant to section 10 of the ESA, or by the terms of an
incidental take statement in a biological opinion pursuant to section 7
of the ESA; (2) Federally approved projects that involve activities
such as agriculture, managed fisheries, road construction, discharge of
fill material, stream channelization, or diversion for which
consultation under section 7 of the ESA has been completed, and when
such activity is conducted in accordance with any terms and conditions
given by NMFS in an incidental take statement in a biological opinion
pursuant to section 7 of the ESA; (3) continued possession of live
Atlantic sturgeon that were in captivity or in a controlled environment
(e.g., in aquaria) at the time of this listing, so long as the
prohibitions under an ESA section 9(a)(1) are not violated. If listed,
NMFS will provide contact information for facilities to submit
information on Atlantic sturgeon in their possession, to establish
their claim of possession; and (4) provision of care for live Atlantic
sturgeon that were in captivity at the time of this listing.
Section 9(b)(1) of the ESA provides a narrow exemption for animals
held in captivity at the time of listing: Those animals are not subject
to the import/export prohibition or to protective regulations adopted
by the Secretary, so long as the holding of the species in captivity,
before and after listing, is not in the course of a commercial
activity; however, 180 days after listing, there is a rebuttable
presumption that the exemption does not apply. Thus, in order to apply
this exemption, the burden of proof for confirming the status of
animals held in captivity prior to listing lies with the holder. The
section 9(b)(1) exemption for captive wildlife would not apply to any
progeny of the captive animals that may be produced post-listing.
References Cited
A complete list of the references used in this proposed rule is
available upon request (see ADDRESSES).
Classification
National Environmental Policy Act
The 1982 amendments to the ESA, in section 4(b)(1)(A), restrict the
information that may be considered when assessing species for listing.
Based on this limitation of criteria for a listing decision and the
opinion in Pacific Legal Foundation v. Andrus, 675 F. 2d 825 (6th Cir.
1981), NMFS has concluded that ESA listing actions are not subject to
the environmental assessment requirements of the National Environmental
Policy Act (NEPA). (See NOAA Administrative Order 216-6.)
Executive Order 12866, Regulatory Flexibility Act and Paperwork
Reduction Act
As noted in the Conference Report on the 1982 amendments to the
ESA, economic impacts cannot be considered when assessing the status of
a species. Therefore, the economic analysis requirements of the
Regulatory Flexibility Act are not applicable to the listing process.
In addition, this proposed rule is exempt from review under Executive
Order 12866. This proposed rule does not contain a collection-of-
information requirement for the purposes of the Paperwork Reduction
Act.
Federalism
E.O. 13132 requires agencies to take into account any federalism
impacts of regulations under development. It includes specific
consultation directives for situations where a regulation will preempt
state law, or impose substantial direct compliance costs on state and
local governments (unless required by statute). Pursuant to the
Executive Order on Federalism, E.O. 13132, the Assistant Secretary for
Legislative and Intergovernmental Affairs will provide notice of the
proposed action and request comments from the governors of the states
in which the three DPSs proposed to be listed occur.
Environmental Justice
Executive Order 12898 requires that Federal actions address
environmental justice in decision-making process. In particular, the
environmental effects of the actions should not have a disproportionate
effect on minority and low-income communities. The proposed listing
determination is not expected to have a disproportionately high effect
on minority populations or low-income populations.
Coastal Zone Management Act (16 U.S.C. 1451 et seq.)
Section 307(c)(1) of the Federal Coastal Zone Management Act of
1972 requires that all Federal activities that affect any land or water
use or natural resource of the coastal zone be consistent with approved
state coastal zone management programs to the maximum extent
practicable. NMFS has determined that this action is consistent to the
maximum extent practicable with the enforceable policies of approved
Coastal Zone Management Programs of each of the states within the range
of the three DPSs. Letters documenting NMFS' determination, along with
the proposed rule, were sent to the coastal zone management program
offices in each affected state. A list of the specific state contacts
and a copy of the letters are available upon request.
List of Subjects
50 CFR Part 223
Administrative practice and procedure, Endangered and threatened
species, Exports, Imports, Reporting and recordkeeping requirements,
Transportation.
50 CFR Part 224
Endangered and threatened species, Exports, Imports.
Dated: September 23, 2010.
Eric C. Schwaab,
Assistant Administrator for Fisheries, National Marine Fisheries
Service.
For the reasons set out in the preamble, 50 CFR parts 223 and 224
are proposed to be amended as follows:
[[Page 61902]]
PART 223--THREATENED MARINE AND ANADROMOUS SPECIES
1. The authority citation for part 223 continues to read as
follows:
Authority: 16 U.S.C. 1531-1543; subpart B, Sec. 223.201-202
also issued under 16 U.S.C. 1361 et seq.; 16 U.S.C. 5503(d) for
Sec. 223.206(d)(9).
2. In Sec. 223.102, paragraph (c)(29) is added to read as follows:
Sec. 223.102 Enumeration of threatened marine and anadromous species.
* * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species \1\
------------------------------------------------------------------- Where listed Citation(s) for listing Citation(s) for critical
Common name Scientific name determination(s) habitat designation(s)
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
(c) * * *
(29) Atlantic Sturgeon--Gulf of Acipenser oxyrinchus oxyrinchus. Gulf of Maine Distinct [INSERT FR CITATION & DATE
Maine DPS*. Population Segment. The WHEN PUBLISHED AS A FINAL
GOM DPS includes the RULE].
following: All anadromous
Atlantic sturgeon whose
range occurs in
watersheds from the Maine/
Canadian border and
extending southward to
include all associated
watersheds draining into
the Gulf of Maine as far
south as Chatham, MA, as
well as wherever these
fish occur in coastal
bays and estuaries and
the marine environment.
Within this range,
Atlantic sturgeon have
been documented from the
following rivers:
Penobscot, Kennebec,
Androscoggin, Sheepscot,
Saco, Piscataqua, and
Merrimack. The marine
range of Atlantic
sturgeon from the GOM DPS
extends from the Bay of
Fundy, Canada to the
Saint Johns River, FL.
The GOM DPS also includes
Atlantic sturgeon held in
captivity (e.g.,
hatcheries, scientific
institutions) and which
are identified as fish
belonging to the GOM DPS
based on genetics
analyses, previously
applied tags, previously
applied marks, or
documentation to verify
that the fish originated
from (hatched in) a river
within the range of the
GOM DPS, or is the
progeny of any fish that
originated from a river
within the range of the
GOM DPS.
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Species includes taxonomic species, subspecies, distinct population segments (DPSs) (for a policy statement, see 61 FR 4722, February 7, 1996), and
evolutionarily significant units (ESUs) (for a policy statement, see 56 FR 58612, November 20, 1991).
* * * * *
PART 224--ENDANGERED MARINE AND ANADROMOUS SPECIES
3. The authority citation for part 224 continues to read as
follows:
Authority: 16 U.S.C. 1531-1543 and 16 U.S.C. 1361 et seq.
4. In Sec. 224.101(a), amend the table by adding entries for
Atlantic Sturgeon-New York Bight DPS, and Atlantic Sturgeon-Chesapeake
Bay DPS at the end of the table to read as follows:
Sec. 224.101 Enumeration of endangered marine and anadromous species
* * * * *
(a) * * *
[[Page 61903]]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species \1\
------------------------------------------------------------------- Where listed Citation(s) for listing Citation(s) for critical
Common name Scientific name determination(s) habitat designation(s)
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
Atlantic Sturgeon--New York Acipenser oxyrinchus oxyrinchus. New York Bight Distinct [INSERT FR CITATION & DATE NA
Bight DPS. Population Segment. The WHEN PUBLISHED AS A FINAL
NYB DPS includes the RULE].
following: All anadromous
Atlantic sturgeon whose
range occurs in the
watersheds that drain
into coastal waters,
including Long Island
Sound, the New York
Bight, and Delaware Bay,
from Chatham, MA to the
Delaware-Maryland border
on Fenwick Island. Within
this range, Atlantic
sturgeon have been
documented from the
Hudson and Delaware
rivers as well as at the
mouth of the Connecticut
and Taunton rivers, and
throughout Long Island
Sound. The marine range
of Atlantic sturgeon from
the NYB DPS extends from
the Bay of Fundy, Canada
to the Saint Johns River,
FL. The NYB DPS also
includes Atlantic
sturgeon held in
captivity (e.g.,
hatcheries, scientific
institutions) and which
are identified as fish
belonging to the NYB DPS
based on genetics
analyses, previously
applied tags, previously
applied marks, or
documentation to verify
that the fish originated
from (hatched in) a river
within the range of the
NYB DPS, or is the
progeny of any fish that
originated from a river
within the range of the
NYB DPS.
Atlantic Sturgeon--Chesapeake Acipenser oxyrinchus oxyrinchus. Chesapeake Bay Distinct [INSERT FR CITATION & DATE NA
Bay DPS. Population Segment. The WHEN PUBLISHED AS A FINAL
CB DPS includes the RULE].
following: All anadromous
Atlantic sturgeon whose
range occurs in the
watersheds that drain
into the Chesapeake Bay
and into coastal waters
from the Delaware-
Maryland border on
Fenwick Island to Cape
Henry, VA, as well as
wherever these fish occur
in coastal bays and
estuaries and the marine
environment. Within this
range, Atlantic sturgeon
have been documented from
the James, York, Potomac,
Rappahannock, Pocomoke,
Choptank, Little
Choptank, Patapsco,
Nanticoke, Honga, and
South rivers as well as
the Susquehanna Flats.
The marine range of
Atlantic sturgeon from
the CB DPS extends from
the Bay of Fundy, Canada
to the Saint Johns River,
FL. The CB DPS also
includes Atlantic
sturgeon held in
captivity (e.g.,
hatcheries, scientific
institutions) and which
are identified as fish
belonging to the CB DPS
based on genetics
analyses, previously
applied tags, previously
applied marks, or
documentation to verify
that the fish originated
from (hatched in) a river
within the range of the
CB DPS, or is the progeny
of any fish that
originated from a river
within the range of the
CB DPS.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Species includes taxonomic species, subspecies, distinct population segments (DPSs) (for a policy statement, see 61 FR 4722, February 7, 1996), and
evolutionarily significant units (ESUs) (for a policy statement, see 56 FR 58612, November 20, 1991).
[[Page 61904]]
* * * * *
[FR Doc. 2010-24459 Filed 10-5-10; 8:45 am]
BILLING CODE 3510-22-P