Endangered and Threatened Wildlife and Plants: Final Rulemaking To Designate Critical Habitat for the Threatened Southern Distinct Population Segment of North American Green Sturgeon, 52300-52351 [E9-24067]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 74, Number 195 (Friday, October 9, 2009)]
[Rules and Regulations]
[Pages 52300-52351]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E9-24067]



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Part II





Department of Commerce





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National Oceanic and Atmospheric Administration



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50 CFR Part 226



Endangered and Threatened Wildlife and Plants: Final Rulemaking To 
Designate Critical Habitat for the Threatened Southern Distinct 
Population Segment of North American Green Sturgeon; Final Rule

Federal Register / Vol. 74, No. 195 / Friday, October 9, 2009 / Rules 
and Regulations

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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 226

[Docket No. 080730953-91263-02]
RIN 0648-AX04


Endangered and Threatened Wildlife and Plants: Final Rulemaking 
To Designate Critical Habitat for the Threatened Southern Distinct 
Population Segment of North American Green Sturgeon

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

ACTION: Final rule.

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SUMMARY: We, the National Marine Fisheries Service (NMFS), designate 
critical habitat for the threatened Southern distinct population 
segment of North American green sturgeon (Southern DPS of green 
sturgeon) pursuant to section 4 of the Endangered Species Act (ESA). 
Specific areas proposed for designation include: Coastal U.S. marine 
waters within 60 fathoms (fm) depth from Monterey Bay, California 
(including Monterey Bay), north to Cape Flattery, Washington, including 
the Strait of Juan de Fuca, Washington, to its United States boundary; 
the Sacramento River, lower Feather River, and lower Yuba River in 
California; the Sacramento-San Joaquin Delta and Suisun, San Pablo, and 
San Francisco bays in California; the lower Columbia River estuary; and 
certain coastal bays and estuaries in California (Humboldt Bay), Oregon 
(Coos Bay, Winchester Bay, Yaquina Bay, and Nehalem Bay), and 
Washington (Willapa Bay and Grays Harbor). This rule designates 
approximately 515 kilometer (km) (320 miles (mi)) of freshwater river 
habitat, 2,323 km\2\ (897 mi\2\) of estuarine habitat, 29,581 km\2\ 
(11,421 mi\2\) of marine habitat, 784 km (487 mi) of habitat in the 
Sacramento-San Joaquin Delta, and 350 km\2\ (135 mi\2\) of habitat 
within the Yolo and Sutter bypasses (Sacramento River, CA) as critical 
habitat for the Southern DPS of green sturgeon.
    This rule excludes the following areas from designation because the 
economic benefits of exclusion outweigh the benefits of inclusion and 
exclusion will not result in the extinction of the species: Coastal 
U.S. marine waters within 60 fm depth from the California/Mexico border 
north to Monterey Bay, CA, and from the Alaska/Canada border northwest 
to the Bering Strait; the lower Columbia River from river kilometer 
(RKM) 74 to the Bonneville Dam; and certain coastal bays and estuaries 
in California (Elkhorn Slough, Tomales Bay, Noyo Harbor, and the 
estuaries to the head of the tide in the Eel and Klamath/Trinity 
rivers), Oregon (Tillamook Bay and the estuaries to the head of the 
tide in the Rogue, Siuslaw, and Alsea rivers), and Washington (Puget 
Sound). Particular areas are also excluded based on impacts on national 
security and impacts on Indian lands. The areas excluded from the 
designation comprise approximately 0.2 km (0.1 mi) of freshwater 
habitat, 2,945 km\2\ (1,137 mi\2\) of estuarine habitat and 1,034,935 
km\2\ (399,590 mi\2\) of marine habitat.
    This final rule responds to and incorporates public comments 
received on the proposed rule and supporting documents, as well as peer 
reviewer comments received on the draft biological report and draft ESA 
section 4(b)(2) report.

DATES: This rule will take effect on November 9, 2009.

ADDRESSES: Reference materials regarding this determination can be 
obtained via the Internet at: https://www.nmfs.noaa.gov or by submitting 
a request to the Assistant Regional Administrator, Protected Resources 
Division, Southwest Region, NMFS, 501 West Ocean Blvd., Suite 4200, 
Long Beach, CA 90802-4213.

FOR FURTHER INFORMATION CONTACT: Melissa Neuman, NMFS, Southwest Region 
(562) 980-4115; Steve Stone, NMFS, Northwest Region (503) 231-2317; or 
Lisa Manning, NMFS, Office of Protected Resources (301) 713-1401.

SUPPLEMENTARY INFORMATION:

Background

    Under the ESA, we are responsible for determining whether certain 
species, subspecies, or distinct population segments (DPS) are 
threatened or endangered, and designating critical habitat for them (16 
U.S.C. 1533). On April 7, 2006, we determined that the Southern DPS of 
green sturgeon is likely to become endangered in the foreseeable future 
throughout all or a significant portion of its range and listed the 
species as threatened under the ESA (71 FR 17757). A proposed critical 
habitat rule for the Southern DPS was published in the Federal Register 
on September 8, 2008 (73 FR 52084), with a technical correction and 
notification of a public workshop published on October 7, 2008 (73 FR 
58527). Pursuant to a court-ordered settlement agreement, NMFS agreed 
to make a final critical habitat designation for the Southern DPS by 
June 30, 2009. However, an extension was requested and granted, with a 
new deadline of October 1, 2009. This rule describes the final critical 
habitat designation, including responses to public comments and peer 
reviewer comments, a summary of changes from the proposed rule, and 
supporting information on green sturgeon biology, distribution, and 
habitat use, and the methods used to develop the final designation.
    We considered various alternatives to the critical habitat 
designation for the green sturgeon. The alternative of not designating 
critical habitat for the green sturgeon would impose no economic, 
national security, or other relevant impacts, but would not provide any 
conservation benefit to the species. This alternative was considered 
and rejected because such an approach does not meet the legal 
requirements of the ESA and would not provide for the conservation of 
green sturgeon. The alternative of designating all potential critical 
habitat areas (i.e., no areas excluded) also was considered and 
rejected because, for a number of areas, the economic benefits of 
exclusion outweighed the benefits of inclusion, and NMFS did not 
determine that exclusion of these areas would significantly impede 
conservation of the species or result in extinction of the species. The 
total estimated annualized economic impact associated with the 
designation of all potential critical habitat areas would be $64 
million to $578 million (discounted at 7 percent) or $63.9 million to 
$578 million (discounted at 3 percent).
    An alternative to designating critical habitat within all of the 
units considered for designation is the designation of critical habitat 
within a subset of these units. Under section 4(b)(2) of the ESA, NMFS 
must consider the economic impacts, impacts to national security, and 
other relevant impacts of designating any particular area as critical 
habitat. NMFS has the discretion to exclude an area from designation as 
critical habitat if the benefits of exclusion (i.e., the impacts that 
would be avoided if an area were excluded from the designation) 
outweigh the benefits of designation (i.e., the conservation benefits 
to the Southern DPS if an area were designated), so long as exclusion 
of the area will not result in extinction of the species. Exclusion 
under section 4(b)(2) of the ESA of one or more of the units considered 
for designation would reduce the total impacts of designation. The 
determination of which units and how many to exclude depends on NMFS' 
ESA 4(b)(2) analysis, which is conducted for each unit and described

[[Page 52301]]

in detail in the ESA 4(b)(2) analysis report. Under this preferred 
alternative, NMFS originally proposed to exclude 13 out of 40 units 
considered. The total estimated economic impact associated with the 
proposed rule was $22.5 million to $76.4 million (discounted at 7 
percent) or $22.5 million to $76.3 million (discounted at 3 percent). 
In response to public comments and additional information received, 
this final rule excludes 14 units out of 41 units considered where the 
economic benefits of exclusion outweighed the conservation benefits of 
designation. NMFS determined that the exclusion of these 14 units would 
not significantly impede the conservation of the Southern DPS. The 
total estimated economic impact associated with this final rule is 
$20.2 million to $74.1 million (discounted at 7 percent) or $20.1 
million to $74 million (discounted at 3 percent). NMFS selected this 
alternative because it results in a critical habitat designation that 
provides for the conservation of the Southern DPS while reducing the 
economic impacts on entities. This alternative also meets the 
requirements under the ESA and our joint NMFS-USFWS regulations 
concerning critical habitat.

Green Sturgeon Natural History

    The green sturgeon (Acipenser medirostris) is an anadromous fish 
species that is long-lived and among the most marine oriented sturgeon 
species in the family Acipenseridae. Green sturgeon is one of two 
sturgeon species occurring on the U.S. west coast, the other being 
white sturgeon (Acipenser transmontanus). Green sturgeon range from the 
Bering Sea, Alaska, to Ensenada, Mexico, with abundance increasing 
north of Point Conception, CA (Moyle et al. 1995). Green sturgeon 
occupy freshwater rivers from the Sacramento River up through British 
Columbia (Moyle 2002), but spawning has been confirmed in only three 
rivers, the Rogue River in Oregon and the Klamath and Sacramento rivers 
in California. Based on genetic analyses and spawning site fidelity 
(Adams et al. 2002; Israel et al. 2004), NMFS has determined green 
sturgeon are comprised of at least two distinct population segments 
(DPSs): (1) A Northern DPS consisting of populations originating from 
coastal watersheds northward of and including the Eel River (i.e., the 
Klamath and Rogue rivers) (``Northern DPS''); and (2) a southern DPS 
consisting of populations originating from coastal watersheds south of 
the Eel River, with the only known spawning population in the 
Sacramento River (``Southern DPS''). The Northern DPS and Southern DPS 
are distinguished based on genetic data and spawning locations, but 
their distribution outside of natal waters generally overlap with one 
another (Chadwick 1959; Miller 1972; California Department of Fish and 
Game (CDFG) 2002; Israel et al. 2004; Moser and Lindley 2007; Erickson 
and Hightower 2007; Lindley et al. 2008.). Both Northern DPS and 
Southern DPS green sturgeon occupy coastal estuaries and coastal marine 
waters from southern California to Alaska, including Humboldt Bay, the 
lower Columbia river estuary, Willapa Bay, Grays Harbor, and coastal 
waters between Vancouver Island, BC, and southeast Alaska (Israel et 
al. 2004; Moser and Lindley 2007; Lindley et al. 2008).
    Spawning frequency is not well known, but the best information 
suggests adult green sturgeon spawn every 2--4 years (pers. comm. with 
Steve Lindley, NMFS, and Mary Moser, NMFS, 2004, cited in 70 FR 17386, 
April 6, 2005; Erickson and Webb 2007). Beginning in late February, 
adult green sturgeon migrate from the ocean into fresh water to begin 
their spawning migrations (Moyle et al. 1995). Spawning occurs from 
March to July, with peak activity from mid-April to mid-June (Emmett et 
al. 1991; Poytress et al. 2009). Spawning in the Sacramento River 
occurs in fast, deep water over gravel, cobble, or boulder substrates 
(Emmett et al. 1991; Moyle et al. 1995; Poytress et al. 2009). Eggs and 
larvae develop in freshwater, likely near the spawning site (Kynard et 
al. 2005). Development of early life stages is affected by water flow 
and temperature (optimal temperatures from 11 to 17-18 [deg]C; Cech et 
al. 2000, cited in COSEWIC 2004; Van Eenennaam et al. 2005). Juvenile 
green sturgeon rear and feed in fresh and estuarine waters from 1 to 4 
years prior to dispersing into marine waters as subadults (Nakamoto et 
al. 1995).
    Adults are defined as sexually mature fish, subadults as sexually 
immature fish that have entered into coastal marine waters (usually at 
3 years of age), and juveniles as fish that have not yet made their 
first entry into marine waters. Green sturgeon spend a large portion of 
their lives in coastal marine waters as subadults and adults. Subadult 
male and female green sturgeon spend at least approximately 6 and 10 
years, respectively, at sea before reaching reproductive maturity and 
returning to freshwater to spawn for the first time (Nakamoto et al. 
1995). Adult green sturgeon spend as many as 2-4 years at sea between 
spawning events (pers. comm. with Steve Lindley, NMFS, and Mary Moser, 
NMFS, cited in 70 FR 17386, April 6, 2005; Erickson and Webb 2007). 
Prior to reaching sexual maturity and between spawning years, subadults 
and adults occupy coastal estuaries adjacent to their natal rivers, as 
well as throughout the West coast, and coastal marine waters within 110 
meters (m) depth. Green sturgeon inhabit certain estuaries on the 
northern California, Oregon, and Washington coasts during the summer, 
and inhabit coastal marine waters along the central California coast 
and between Vancouver Island, British Columbia, and southeast Alaska 
over the winter (Lindley et al. 2008). Green sturgeon likely inhabit 
these estuarine and marine waters to feed and to optimize growth (Moser 
and Lindley 2007). Particularly large aggregations of green sturgeon 
occur in the Columbia River estuary and Washington estuaries and 
include green sturgeon from all known spawning populations (Moser and 
Lindley 2007). Although adult and subadult green sturgeon occur in 
coastal marine waters as far north as the Bering Sea, green sturgeon 
have not been observed in freshwater rivers or coastal bays and 
estuaries in Alaska.
    Detailed information on the natural history of green sturgeon is 
provided in the proposed rule to designate critical habitat (73 FR 
52084; September 8, 2008) and in the final biological report (NMFS 
2009a) prepared in support of this final rule.

Summary of Comments and Responses

    We requested comments on the proposed rule to designate critical 
habitat for the Southern DPS of green sturgeon (73 FR 52084; September 
8, 2008) and on the supporting documents (i.e., the draft biological 
report, draft economic analysis report, and draft ESA section 4(b)(2) 
report). To facilitate public participation, the proposed rule and 
supporting documents were made available on our Southwest Region Web 
site (https://swr.nmfs.noaa.gov) and on the Federal eRulemaking Portal 
Web site (https://www.regulations.gov). Public comments were accepted 
via standard mail, fax, or through the Federal eRulemaking Portal. In 
response to requests from the public, the original 60-day public 
comment period was extended an additional 45 days (73 FR 65283; 
November 3, 2008), ending on December 22, 2008. A public workshop was 
held in Sacramento, CA, on October 16, 2008, and attended by 21 
participants, including researchers and representatives from industries 
and Federal, State, and local agencies. The draft biological report and 
draft

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economic analysis report were also each reviewed by three peer 
reviewers.
    Thirty-nine written public comments were received on the proposed 
rule and supporting documents from Federal agencies, State agencies, 
local entities, non-governmental organizations, Tribes, and industry 
representatives. Seven comments generally supported the proposed rule, 
29 comments did not agree with the designation of critical habitat in 
particular areas, and 3 comments provided additional information but 
did not support or oppose the proposed rule. Several commenters 
requested that certain particular areas or specific areas be considered 
ineligible for designation because they do not meet the definition of 
critical habitat. Several commenters also requested exclusion of areas 
based on economic impacts, impacts on national security, or impacts on 
Indian lands. Additional data were provided to inform the biological 
and economic analyses, as well as comments regarding the methods used 
in these analyses. NMFS considered all public and peer reviewer 
comments. A summary of the comments by major issue categories and the 
responses thereto are presented here. Similar comments are combined 
where appropriate.

Physical or Biological Features Essential for Conservation

    Comment 1: Several commenters felt that the critical habitat 
designation is not supported by the relatively sparse data and that the 
physical or biological habitat features or primary constituent elements 
(PCE) identified for green sturgeon are too general and vague, such 
that no habitat would exist without them. One commenter noted that the 
level of detail provided on the PCEs in the supplementary information 
section of the proposed rule is greater than the level of detail 
provided in the regulatory text section of the proposed rule.
    Response: The critical habitat designation was developed using the 
best available scientific data, as required by the ESA. We recognize 
that uncertainties exist and have noted where they occur in the final 
rule and supporting documents. When appropriate, we incorporated 
additional data provided by the public comments regarding the PCEs, the 
biological evaluation, and the economic analysis. The level of 
specificity of the PCEs was consistent with that provided in previous 
critical habitat designations (e.g., for West coast salmon and 
steelhead evolutionarily significant units (ESU) and Southern Resident 
killer whales). In addition, specific ranges of values for the PCEs 
cannot be provided (e.g., water flow levels, adequately low contaminant 
levels), because the data are not currently available and because these 
values may vary based on the location, time of year, and other factors 
specific to an area. The level of detail provided in different sections 
of the proposed rule differs because the regulatory text section 
typically provides a more brief description of the PCEs, whereas the 
supplementary information section typically provides a more thorough 
description. The supplementary information section and the supporting 
documents provide additional details to describe the process of the 
critical habitat designation and the biological and economic analyses 
that were conducted in support of the designation, whereas the 
regulatory text reports the final designation.
    Comment 2: One commenter requested clarification regarding how 
acceptably low levels of contaminants would be determined on a case-by-
case basis (as it pertains to the water quality and sediment quality 
PCEs). Specifically, the commenter asked whether case-by-case meant 
that this would be determined for each Permittee/Project (and if so, 
what would be the basis for differentiation) or by contaminant (and if 
so, how this would be determined and disseminated to the public).
    Response: Consultations under section 7 of the ESA on contaminants 
may be conducted on a case-by-case basis for each project or by 
contaminant, depending on the scope of the consultation. NMFS has 
typically dealt with consultations for contaminants, such as 
pesticides, on a project-by-project basis. These consultations have 
generally resulted in recommended measures to avoid exposure of the 
listed species to the contaminants in question, for example, by 
spatially or temporally limiting the introduction of the contaminant 
into waterways occupied by the species. However, the recommended 
measures are site-specific and will vary depending on the site, the 
contaminant(s) in question, the type of use, the purpose of the 
project, and the species potentially affected. NMFS recently conducted 
two consultations on the national level with the Environmental 
Protection Agency (EPA) addressing the registration of pesticides 
containing carbaryl, carbofuran, and methomyl (NMFS 2009b) and 
pesticides containing chlorpyrifos, diazinon, and malathion (NMFS 
2008a). In both consultations, NMFS issued a biological opinion finding 
that the registration of these pesticides would jeopardize the 
continued existence of most listed salmonids and adversely modify 
critical habitat. The reasonable and prudent alternatives provided to 
the EPA recommended labeling requirements that specify criteria for the 
use and application of the pesticides, including no-application buffer 
zones adjacent to salmonid habitat, restrictions on application during 
high wind speeds and when a rain storm is predicted, reporting of any 
fish mortalities within four days, and implementation of a monitoring 
plan for off-channel habitats. To the extent the alternatives minimize 
entry of pesticides into water bodies and result in better information, 
green sturgeon and other aquatic species will benefit.
    Comment 3: One commenter provided additional information from 
recent studies indicating that green sturgeon are more sensitive to 
methylmercury and selenium (two contaminants found in sediments) than 
white sturgeon (Kaufman et al. 2008). The commenter noted that the 
studies were unable to determine a ``no effect'' concentration for 
selenomethionine for green sturgeon, a contaminant found in bays 
including the San Francisco, San Pablo, and Suisun bays and the 
Sacramento-San Joaquin Delta (hereafter, the Delta). The commenter 
stated that it may be unlikely that many areas will qualify as having 
the sediment quality PCE as it is described in the proposed rule.
    Response: We appreciate the updated information regarding the 
sensitivity of green sturgeon to contaminants and have incorporated 
this information into the final rule and biological report. We 
recognize the concern expressed by the commenter that few, if any, 
areas have sediments free of elevated levels of contaminants (i.e., 
levels at which green sturgeon are not negatively affected). This 
brings up two issues. First, whether this affects the eligibility of 
the specific areas considered for designation. Because all of the 
proposed areas containing the sediment quality PCE also contained at 
least one other PCE, the eligibility of the specific areas is not 
affected. Related to this is the question of whether a PCE can be 
considered to exist within an area if it has been altered and degraded 
by past, current, or ongoing activities. The ESA's definition of 
critical habitat focuses on PCEs that may require special management 
considerations or protection. Thus, the ESA recognizes that the PCEs 
may exist at varying levels of quality and allows for the consideration 
of PCEs that have been or may be altered or degraded. Second, this 
brings up the question of how this PCE will be addressed in 
consultations under section 7 of the ESA. The

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specifics of each consultation would vary depending on each project, 
but would likely focus on measures to control the introduction of 
selenium into the environment. The Sacramento River basin is naturally 
very low in selenium and little selenium enters the watercourses from 
the surrounding watershed. Conversely, the San Joaquin River basin, due 
to the geology of the west side of the valley and the human 
agricultural practices conducted in this region, create conditions of 
elevated selenium in the waters of the basin draining the west side and 
running through the valley floor towards the Delta. It should also be 
recognized that selenium is a micronutrient which is necessary for 
life, though toxic at levels above trace amounts. Continued monitoring 
of selenium levels in sediments and research on the sensitivity of 
green sturgeon to this and other contaminants would be supported.

Geographical Area Occupied by the Species

    Comment 4: One commenter stated that the range of the Southern DPS 
needs to be clarified as previous publications in the Federal Register 
do not clearly define the range. Another commenter stated that the 
final decision to list the Southern DPS as threatened under the ESA 
only applied the listing to the population in California and that, 
although Southern DPS green sturgeon move into the Northern DPS' range 
outside California, the protections under the listing do not apply to 
Southern DPS fish once they enter the Northern DPS' range. The 
commenter felt that NMFS should not designate Oregon and Washington 
rivers and marine waters as critical habitat if the species is not 
listed in these areas.
    Response: We acknowledge that in the final listing rule and the 
corresponding regulatory language at 50 CFR 223.102(a)(23), it is 
stated, ``Where listed: USA, CA. The southern DPS includes all spawning 
populations of green sturgeon south of the Eel River (exclusive), 
principally including the Sacramento River green sturgeon spawning 
population.'' This statement limits the listing to the Southern DPS of 
green sturgeon, but does not limit the geographic range to which the 
listing applies. A Southern DPS green sturgeon is defined to originate 
from spawning populations south of the Eel River (i.e., from the 
Sacramento River). Each individual Southern DPS fish carries the 
listing, and the protections afforded to it under the ESA, wherever it 
goes. In other words, a Southern DPS green sturgeon is listed as 
threatened and protected under the ESA no matter where that individual 
is found. Thus, Southern DPS green sturgeon are listed throughout their 
range, including waters north of California within the range of the 
Northern DPS.
    NMFS recognizes that previous publications in the Federal Register 
have defined the range of Southern DPS green sturgeon with varying 
levels of specificity and that this may have resulted in confusion. The 
range of the Southern DPS is more clearly defined in the proposed 
critical habitat rule and in the draft biological report (NMFS 2008b). 
We restate this definition here to further clarify the definition and 
range of the Southern DPS of green sturgeon. The proposed critical 
habitat rule (73 FR 52084, September 8, 2008) and the draft biological 
report (NMFS 2008b) define the Southern DPS as consisting of 
populations originating from coastal watersheds south of the Eel River, 
with the only confirmed spawning population in the Sacramento River. 
The Northern DPS consists of populations originating from coastal 
watersheds northward of and including the Eel River, with the only 
confirmed spawning populations in the Klamath and Rogue rivers. Thus, 
the Northern DPS and the Southern DPS of green sturgeon are defined 
based on their natal streams. However, the ranges of the Northern DPS 
and Southern DPS are defined by the distribution of each DPS including 
and beyond their natal waters. Based on genetic information and 
telemetry data from tagged Southern DPS green sturgeon, the occupied 
geographic range of the Southern DPS extends from Monterey Bay, CA, to 
Graves Harbor, AK. Within this geographic range, the presence of 
Southern DPS green sturgeon has been confirmed in the following areas: 
Sacramento River, CA; lower Feather River, CA; lower Yuba River, CA; 
the Sacramento-San Joaquin Delta, CA; Suisun Bay, CA; San Pablo Bay, 
CA; San Francisco Bay, CA; Monterey Bay, CA; Humboldt Bay, CA; Coos 
Bay, OR; Winchester Bay, OR; Yaquina Bay, OR; the lower Columbia River 
and estuary; Willapa Bay, WA; Grays Harbor, WA; the Strait of Juan de 
Fuca, WA; Puget Sound, WA; and Graves Harbor, AK (see final biological 
report (NMFS 2009a) for references for each area). Northern DPS and 
Southern DPS green sturgeon co-occur across much of their occupied 
ranges, are not morphologically distinguishable, and, based on the best 
available data at this time, do not appear to differ in temporal or 
spatial distribution within areas where their ranges overlap. Thus, 
within areas where the Southern DPS has been confirmed, protections for 
the Southern DPS would apply to all green sturgeon based on similarity 
of appearance. The critical habitat designation recognizes not only the 
importance of natal habitats, but of habitats throughout their range 
for the conservation of Southern DPS green sturgeon.
    Comment 5: One commenter stated that the genetic analysis does not 
provide sufficient information to determine the presence or absence of 
Southern DPS green sturgeon in the bays and estuaries on the Oregon 
coast.
    Response: To determine the presence of Southern DPS green sturgeon 
in an area, a critical habitat review team (CHRT), comprised of 9 
Federal biologists from various agencies, primarily relied on the best 
available information from tagging studies. Monitoring of tagged 
Southern DPS green sturgeon has confirmed their use of several coastal 
bays and estuaries from Monterey Bay, California, north to Puget Sound, 
Washington (Moser and Lindley 2007; Lindley et al. 2008; pers. comm. 
with Steve Lindley, NMFS, and Mary Moser, NMFS, February 24-25, 2008). 
Therefore, presence has already generally been established based on the 
tagging data. The available genetic data supports the tagging data by 
assigning or confirming the DPS of individuals (e.g., assigning 
individuals caught in non-natal waters to the Northern DPS or Southern 
DPS) and has also been useful in estimating what proportion of green 
sturgeon observed in non-natal estuaries belong to the Southern DPS. In 
addition, the genetic data would provide supplemental presence 
information once the data set is large enough to ensure detection of 
Southern DPS fish, particularly if the estuary or bay has a low 
frequency of use.
    Comment 6: One commenter requested that additional telemetry data 
regarding green sturgeon use of coastal marine waters at Siletz Reef 
and Seal Rock Reef off the coast of Oregon be incorporated into the 
final biological report and considered in the final critical habitat 
designation. The commenter also requested that additional information 
be included to support the designation of coastal marine waters from 0 
to 20 m depth and from 90 to 110 m depth.
    Response: NMFS is currently analyzing the data on green sturgeon 
detections off the Oregon coast. Preliminary results indicate that 
green sturgeon use deeper depths (between 40 to 80 m) more than 
shallower depths, but reasons for this observation are not known. 
Detection data for shallower depths may be affected by noise. However, 
because these data represent

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only two areas along the Oregon coast, it may not be appropriate to 
extrapolate these observations to other areas along the West coast. 
Other available data indicate that green sturgeon occur throughout all 
depths from 0 to 110 m depth. Some green sturgeon have been caught 
deeper than 110 m depth, but the majority occur in waters shallower 
than 110 m depth (Erickson and Hightower 2007).

Specific Areas

    Comment 7: Two commenters felt that the areas proposed for 
designation as critical habitat were too broad. One commenter stated 
that NMFS failed to show that the areas are essential for conservation 
of the Southern DPS. Another commenter suggested that the areas be 
refined based on the spatial and temporal presence of the PCEs. For 
example, the commenter stated that riverine areas designated as 
critical habitat for spawning purposes should be designated only if 
actually used for spawning and only during the time of year that 
spawning occurs, because areas spatially or temporally outside of this 
would not contain the PCEs for spawning. The commenter stated that such 
refinement would help ensure that the designation is not applied in an 
overly restrictive manner to activities that occur in areas where no 
green sturgeon spawn and that this reasoning can be applied to other 
PCEs and habitat uses.
    Response: The joint NMFS/U.S. Fish and Wildlife Service (USFWS) 
regulations regarding the designation of critical habitat focus on the 
primary biological or physical constituent elements (PCEs) that are 
essential to the conservation of the species. The ESA states that an 
area qualifies as critical habitat if it is occupied and has one or 
more PCE(s) that may require special management considerations or 
protection. Specific areas are eligible for designation if they meet 
these criteria. Neither the ESA definition of critical habitat nor the 
joint NMFS/USFWS regulations require that critical habitat be 
designated only within the most important core habitats of the species.
    In addition, the ESA focuses on the spatial presence of the PCEs, 
but does not mention the temporal presence of the PCEs. The level of 
refinement described by the commenter is typically considered during 
the consultation process under section 7 of the ESA, not during the 
critical habitat designation process. Consistent with ESA section 7 
consultation practices, spatial and temporal considerations are 
commonly assessed during the impact analysis of the proposed action. 
While temporal considerations generally look at impacts to individual 
fish (i.e., avoidance of exposure as inferred by work windows), actions 
can, and often do, affect the habitat that fish use or occupy after the 
action is completed. The commenter's example of spawning areas does not 
address what potential impacts the ``action'' may have on the quality 
of the spawning area after the action is completed. Actions that 
temporally avoid areas of use (i.e., spawning activities on the 
spawning grounds) during the implementation of the action may still 
impact the use of the area after the action is completed. For example, 
installing bridge piers upstream of a spawning area still impacts the 
spawning area after-the-fact through road runoff entering the river 
channel from the bridge, traffic vibrations being transmitted through 
the column into the substrate of the river channel during ``normal 
use,'' and sedimentation from roadway runoff and altered riparian 
habitat. Furthermore, actions that do not occur exactly in the same 
place as the area of concern may nonetheless still affect the area of 
concern. For example, wastewater discharge upstream of a spawning area 
can generate an effluent plume that travels downstream to spawning 
areas, and reservoir releases occurring upstream may affect water flow, 
velocity, and temperature in the area of concern. Thus, details such as 
the specific activities being conducted, the location, and the spatial 
and temporal scale are considered in order to determine the potential 
effects of the activity on critical habitat and, ultimately, whether 
the activity is likely to destroy or adversely modify critical habitat. 
Then a determination is made of what, if any, additional actions or 
modifications to the proposed action will need to be implemented to 
provide protection to the species and their designated critical 
habitat. The section 7 consultation process allows NMFS to address the 
action's impacts on a case-by-case basis and incorporate the 
appropriate level of analysis as needed. A categorical exemption would 
not allow this level of review to occur and in fact would diminish the 
ability to consistently and accurately assess action impacts and adjust 
actions to fit the current status of the species and the condition of 
the critical habitat used by the species.
    Comment 8: One commenter suggested that the shoreward boundary for 
coastal marine habitats should extend to the line of mean lower low 
water (MLLW) instead of extreme high tide, and that the seaward 
boundary of 110 m depth should be rounded to the 60 fm contour line.
    Response: The CHRT, a team of Federal biologists who conducted the 
biological analysis, considered and agreed with the recommendations. 
The area between the MLLW line and the extreme high tide line along the 
coast is small and likely not occupied by green sturgeon. Whereas 
studies indicate that intertidal zones within estuaries and protected 
bays are important habitat for green sturgeon, green sturgeon likely do 
not occupy shallow intertidal areas or high energy surf zones along the 
open coast. The CHRT compared the MLLW line along the coast with the 
extreme high tide line and found that the area that would be excluded 
by defining the shoreward boundary using the MLLW line would be small 
and would not contain any areas identified to be important for green 
sturgeon. Thus, the CHRT agreed to extend the coastal marine areas to 
the area inundated by mean lower low water, rather than to the extreme 
high tide. The CHRT also agreed to round the 110 m depth contour line 
to the 60 fm contour line, because the 60-fm contour is already 
described in Federal regulations for the West Coast groundfish bottom 
trawl fishery and is approximately equal to 110 m (60 fm = 109.7 m).
    Comment 9: Several comments were received regarding the proposed 
designation of the lower Columbia River estuary. The commenters felt 
that the geographic definition of the estuary used was too broad and 
that the boundary for the estuary in the lower Columbia River should be 
defined by the maximum extent of saltwater intrusion, which was defined 
by one commenter to occur at RKM 64 and another commenter to occur at 
RKM 74. The commenters recommended that the Willamette River and the 
lower Columbia River from RKM 64 or RKM 74 to Bonneville Dam should be 
excluded from the designation. One commenter asserted that there are no 
data indicating that green sturgeon captured above Columbia RKM 64 are 
part of the Southern DPS, and that because recent green sturgeon 
tagging data indicate that Northern DPS green sturgeon occupy more 
interior habitats in the Columbia River estuary than Southern DPS green 
sturgeon, a smaller critical habitat area for the Columbia River 
estuary is justified.
    Response: In the proposed rule, the specific area in the lower 
Columbia River estuary was defined as the area from the river mouth to 
the Bonneville Dam (RKM 146). The CHRT considered the comments received 
and agreed that this specific area should be divided into

[[Page 52305]]

two specific areas as follows: (1) The lower Columbia River estuary 
from the river mouth to RKM 74; and (2) the lower Columbia River from 
RKM 74 to the Bonneville Dam (RKM 146). This division was based on 
differences in environmental parameters and green sturgeon use and 
presence between the lower estuary (river mouth to RKM 74) and the 
lower river (RKM 74 to Bonneville Dam). River kilometer 74 marks the 
approximate location of the maximum extent of saltwater intrusion into 
the lower Columbia River and has been used in other reports as the 
location to divide the lower estuary and tidal freshwater (Johnson et 
al. 2003). Commercial gillnet harvest data for green sturgeon from 
1981-2004 (Washington Department of Fish and Wildlife (WDFW) 2007, ESA 
informal consultation) indicate the greatest numbers of green sturgeon 
catch in zone 1 (RKM 1-32; 29,124 green sturgeon harvested) and zone 2 
(RKM 32-84; 8,082 green sturgeon harvested). Green sturgeon catch 
declines sharply upstream of RKM 84, with a total of 290 green sturgeon 
caught in zones 3-5 (RKM 84-227) from 1981-2004. Observations by WDFW 
and Oregon Department of Fish and Wildlife (ODFW) also indicate 
concentrations of green sturgeon in the lower estuary with fewer 
numbers moving upstream. Unpublished telemetry data support these 
observations, showing greater numbers of detections of both Southern 
DPS and Northern DPS green sturgeon in the lower portion of the estuary 
compared to the upper portion (pers. comm. with Mary Moser, NMFS, 
February 25, 2009). However, because the most upstream monitor location 
is at RKM 74, the telemetry data provide data on the distribution of 
tagged Southern DPS and Northern DPS fish within the lower estuary but 
do not provide data on the movement and distribution of tagged green 
sturgeon upstream of RKM 74. Tagged Southern DPS green sturgeon have 
been detected at the monitor at RKM 74 and are able to access the lower 
Columbia River upstream of RKM 74, though data are not available to 
determine the number of Southern DPS green sturgeon moving upstream of 
RKM 74 or the relative levels of Southern DPS and Northern DPS fish in 
this area. Based on information provided in the public comments 
indicating that green sturgeon have not been observed in the lower 
Willamette River, the CHRT agreed that the Willamette River should not 
be included in the areas considered for designation. Thus, the specific 
area delineated in the lower Columbia River from RKM 74 to the 
Bonneville Dam does not now include the Willamette River. The CHRT's 
evaluation of the two specific areas resulted in a conservation value 
rating of High for the lower Columbia River estuary from the river 
mouth to RKM 74 and a conservation value rating of Low for the lower 
Columbia River from RKM 74 to RKM 146 (see response to Comment 14 and 
the section titled ``Methods for Assessment of Specific Areas'' for an 
explanation of how the conservation value ratings were determined). The 
final biological report (NMFS 2009a) provides additional information 
about the CHRT's evaluation of each specific area.
    Comment 10: One commenter recommended that South San Francisco Bay 
be considered a separate area from Central San Francisco Bay and that 
South San Francisco Bay should be excluded from the designation because 
use of the area by green sturgeon is moderate and it is not needed for 
any life history stage that is not supported by the northern reach of 
the Bay.
    Response: The CHRT acknowledged that Central San Francisco Bay and 
South San Francisco Bay can be distinguished by different environmental 
and oceanographic features. However, these differences likely do not 
affect green sturgeon use of the areas. The best available catch data 
for the San Francisco Bay indicate that comparably low numbers of green 
sturgeon have been caught in both Central and South San Francisco Bay. 
In 2006, a local sport fishing group reported 2 green sturgeon caught 
in Central San Francisco Bay, 3 caught in South-Central San Francisco 
Bay, and 4 caught in South San Francisco Bay (pers. comm. with Pete 
Davidson, Coastside Fishing Club, May 31, 2006). The total green 
sturgeon catch in the sport fishery for 2006 is not known, because 
sturgeon report cards were not required in California until March 2007 
(Gleason 2007). Low numbers of green sturgeon were caught in CDFG's 
otter trawl (1980 to 2004) and midwater trawl (1980 to 2001) surveys in 
the bays and the Delta (Delta: n = 19; Suisun Bay/Carquinez Strait: n = 
27; San Pablo Bay: n = 9; Central San Francisco Bay: n = 8; South San 
Francisco Bay: n = 2) (Jahn 2006). It is important to note that the 
surveys and sampling gear were not designed to target green sturgeon, 
and thus the data may not be truly representative of the relative 
levels of green sturgeon use among the bays and the Delta. For example, 
given that all green sturgeon must migrate through Central San 
Francisco Bay in their migrations to and from the ocean, much larger 
numbers of green sturgeon catch would be expected in this area. In 
addition, the catch data do not provide information about the 
distribution of juvenile green sturgeon throughout the bays and the 
Delta. Based on the best available information, juvenile green sturgeon 
are believed to distribute widely throughout the bays and Delta for 
feeding and rearing and are present in all months of the year (Ganssle 
1966, CDFG 2002, Bay Delta and Tributaries Project 2005). Thus, the 
CHRT determined that the best available information does not support 
dividing the specific area in San Francisco Bay into Central San 
Francisco Bay and South San Francisco Bay, and reconfirmed that this 
specific area has a High conservation value for the Southern DPS (see 
response to Comment 14 and the section titled ``Methods for Assessment 
of Specific Areas'' for an explanation of how the conservation value 
ratings were determined). Based on the CHRT's assessment of San 
Francisco Bay, NMFS determined that this area should be included in the 
final critical habitat designation. Studies focused on green sturgeon, 
particularly on the juvenile life stages, would help address the data 
gaps and inform ESA section 7 consultations resulting from this 
critical habitat designation as well as future revisions to the 
designation.
    Comment 11: One commenter recommended consideration of Nehalem Bay, 
Oregon, as a specific area and designation of critical habitat in 
Tillamook Bay, Oregon. Sport fish catch from 1986 to 2007 indicate that 
279 green sturgeon were taken in the fishery in Tillamook Bay 
(corrected catch data provided via pers. comm. with Mary Hanson, ODFW, 
July 16, 2009). The habitat in Tillamook Bay is comparable to other 
Oregon Bays and estuaries, and genetic analyses have not excluded the 
presence of southern DPS green sturgeon. Nehalem Bay was not considered 
in the designation and had a sport fish catch record of 254 green 
sturgeon from 1986 to 2007 (corrected catch data provided via pers. 
comm. with Mary Hanson, ODFW, July 16, 2009). Another commenter stated 
that a tagged Southern DPS green sturgeon was detected in Yaquina Bay, 
Oregon, in May 2006 and recommended that the biological report be 
revised to state that the presence of the Southern DPS in this area is 
confirmed.
    Response: Based on the additional green sturgeon catch and 
telemetry data provided by the commenters, the CHRT added Nehalem Bay 
as a new specific area to be considered and re-evaluated Tillamook Bay 
and Yaquina Bay. The

[[Page 52306]]

CHRT assigned Nehalem Bay a Medium conservation value rating based on 
the large number of green sturgeon captured from 1986 to 2007 and its 
location between Tillamook Bay and the Columbia River. The CHRT also 
assigned Tillamook Bay a Medium conservation value rating (compared to 
its previous Low conservation value rating), based on the large number 
of green sturgeon captured in this bay from 1986 to 2007 and 
information indicating that Tillamook Bay contains suitable depths for 
green sturgeon. The CHRT assigned Yaquina Bay a Low conservation value 
rating, which was the same rating given previously. The CHRT then 
considered whether Southern DPS presence has been confirmed within the 
areas. If Southern DPS green sturgeon presence is likely, but not yet 
confirmed, the conservation value rating was reduced by one level. 
Because Southern DPS green sturgeon have not yet been confirmed in 
Nehalem Bay and Tillamook Bay, the conservation value ratings were 
reduced to Low. Because Southern DPS green sturgeon have been confirmed 
in Yaquina Bay, the conservation value rating stayed at Low and was not 
reduced to Ultra-Low. These ratings were then used as the final 
conservation value ratings for the areas. The final biological report 
provides more information about the CHRT's evaluation of Nehalem Bay 
and re-evaluation of Tillamook Bay and Yaquina Bay. Ultimately only 
Tillamook Bay was excluded because the benefits of exclusion outweigh 
the benefits of designation.
    Comment 12: Two commenters felt that the Umpqua River may warrant 
designation because green sturgeon occur in this river, and it was 
identified as a potential spawning river in the 2005 status review.
    Response: The CHRT evaluated Winchester Bay, the estuary at the 
mouth of the Umpqua River, as a specific area eligible for designation 
as critical habitat. The Southern DPS consists of green sturgeon 
originating from coastal watersheds south of the Eel River, CA 
(currently, the only confirmed spawning river is the Sacramento River, 
CA). The Northern DPS consists of green sturgeon originating from 
coastal watersheds north of and including the Eel River, CA (confirmed 
spawning rivers are the Klamath River, CA, and Rogue River, OR). As 
described in the proposed rule and biological report, NMFS defined the 
Southern DPS' occupied range to include coastal bays and estuaries 
upstream to the head of the tide in areas north of and including the 
Eel River. In waters north of and including the Eel River, green 
sturgeon occurring upstream of the head of the tide are presumed to 
belong to the Northern DPS because it is unlikely that Southern DPS 
green sturgeon would venture further into non-natal streams beyond the 
head of tide. Thus, green sturgeon observed in the Umpqua River 
upstream of the head of tide are presumed to be Northern DPS fish. 
Genetic analyses have confirmed the presence of Southern DPS green 
sturgeon in Winchester Bay and Umpqua River, but the tissue samples 
were collected downstream of the head of tide on the Umpqua River 
(between RKM 6.4 and 19.3). Thus, the available genetic data also do 
not provide information on the presence of Southern DPS green sturgeon 
in the Umpqua River upstream of the head of tide (pers. comm. with Josh 
Israel, University of California, Davis (UC Davis), July 10, 2009). The 
Umpqua River was therefore not identified as an area occupied by the 
Southern DPS.
    Comment 13: One commenter felt that Chinook salmon should be used 
as a surrogate species in place of white sturgeon, because green 
sturgeon do not have populations that are isolated from the sea. The 
commenter presented a Chinook salmon-based conceptual model for the 
life history of green sturgeon in San Francisco Bay, which indicated 
that, like Chinook, juvenile green sturgeon most likely migrate from 
the San Francisco Bay as soon as possible to coastal marine waters 
where food is abundant for feeding and growth.
    Response: The CHRT considered the Chinook salmon-based conceptual 
model. The CHRT noted that, while green sturgeon may share some 
similarities with Chinook salmon with regard to habitat use and needs, 
the best available data indicate there are several important 
differences between the life history and distribution of green sturgeon 
and Chinook salmon that limit the application of the Chinook salmon-
based conceptual model to green sturgeon. Unlike Chinook salmon, green 
sturgeon will transit through the San Francisco Bay and Delta complex 
several times during their lifetime. Laboratory studies indicate that 
Chinook salmon juveniles may occupy fresh to brackish waters at any 
age, but do not completely transition to salt water until about 1.5 
years of age. Studies in the Klamath River show that juvenile green 
sturgeon rear in fresh and estuarine waters for 1 to 4 years before 
dispersing into salt water, at lengths of about 300 to 750 mm. Although 
there have been few studies on juvenile green sturgeon distribution 
throughout the San Francisco Bay, the available data indicate that 
juvenile green sturgeon also rear in the area's bays and estuaries for 
1 to 4 years before migrating out to coastal marine waters as 
subadults. Residence times in the Delta appear to be variable, based on 
the temporal frequency of juvenile fish recovered at the fish salvage 
facilities of the Central Valley Project and State Water Project and 
the data collected from both the 2007 and 2008 sturgeon report cards 
from CDFG (Gleason 2008). Green sturgeon can be found in any month of 
the year, and apparently multiple year classes are present in the Delta 
based on the size distribution of catches, although for green sturgeon 
few fish were actually measured (sizes ranged from 12 inches to 68 
inches, 19 fish measured out of 240 reported caught; Gleason 2008). 
Based on the 2008 report cards, adult green sturgeon were caught by 
sport fishermen in every season of the year in the Delta and in the 
Sacramento River (from Rio Vista to Chipps Island and from Red Bluff to 
Colusa). This year-round presence of adult and juvenile green sturgeon 
in the Central Valley differs from the typical Chinook salmon life 
history as described by the commenter's conceptual model, in which 
juveniles rear in freshwater prior to migrating to the San Francisco 
Bay estuary, through which they move rapidly to get to marine waters, 
where conditions are better for feeding and growth. In addition, 
subadult and adult green sturgeon migrate throughout the West coast 
from southern California to Alaska, and are known to occupy 
oversummering habitats in coastal bays and estuaries from northern 
California to Washington (including Humboldt Bay, Coos Bay, Winchester 
Bay, the lower Columbia River estuary, Willapa Bay, and Grays Harbor) 
for weeks to months to feed during multiple summers over the course of 
their lives. In contrast, Chinook salmon generally use estuaries only 
at the beginning and end of their ocean residence (Quinn 2005). Unlike 
green sturgeon, they spend their summers in the ocean and do not rely 
nearly as heavily on estuarine habitats over their lifespans.

Biological Evaluation of Conservation Value

    Comment 14: One commenter stated that the qualitative approach used 
by the CHRT to assess the biological conservation benefits of 
designation was not adequate because the approach did not provide an 
objective estimate of the relative conservation benefit of including a 
specific area or a clear standard to compare with the estimated 
economic impacts. The commenter

[[Page 52307]]

noted that the approach did not contain an estimate of the species' 
current population level, the increase in survival or abundance 
expected from the designation of critical habitat, or an estimate of 
the economic or monetary value of the conservation benefits.
    Response: The ESA requires that a critical habitat designation be 
based on the best available scientific data. Data are not available 
regarding the current absolute population abundance of the Southern DPS 
or green sturgeon in general. Data are also not available to estimate 
the monetary value of the conservation benefits of designation and 
thereby make a direct comparison to the economic impacts of 
designation. In the absence of these data, a qualitative conservation 
value rating approach was developed to evaluate the conservation 
benefits of designation. The approach incorporated the best available 
data and allowed for consideration of the best professional judgment of 
the CHRT. The conservation value ratings (High, Medium, Low, Ultra-low) 
provided a relative measure of the benefits of designation for each 
specific area, at a level appropriate for the level of data available. 
This approach has been used in critical habitat designations for 
salmonids and has been recognized as an appropriate alternative where 
data are not available to monetize the benefits of designation.
    Comment 15: One commenter recommended that further evaluation of 
whether green sturgeon use particular coastal estuaries and their 
habitat value be conducted prior to designation of these areas as 
critical habitat. The commenter focused on the coastal estuaries 
considered for designation in Oregon, stating that the proposed rule 
did not provide information regarding the use or extent of use by green 
sturgeon in these areas or the habitat value of these areas to green 
sturgeon. Specifically, the commenter stated that: (1) The genetic 
analyses do not provide sufficient information to determine the 
presence of Southern DPS green sturgeon in Winchester Bay and more 
sampling is needed; (2) it is not clear whether tissue samples 
collected for genetic analyses were taken from green sturgeon in 
Winchester Bay or in the Umpqua River and the results regarding the 
proportion of Southern DPS green sturgeon in the area may be affected 
by sample size; (3) it is not clear why the Rogue River was excluded, 
but Coos Bay was not; and (4) reasons for the designation of Yaquina 
Bay and the exclusion of Tillamook Bay and the Siuslaw River estuary 
are not clear.
    Response: We agree that additional studies are needed to address 
information gaps regarding the extent of use of coastal estuaries by 
Northern DPS and Southern DPS green sturgeon and to better understand 
the habitat function and value of these areas for the species. However, 
the ESA requires that NMFS use the best available scientific and 
commercial data to designate critical habitat within specific statutory 
timelines. Thus, in the face of uncertainty and varying levels of 
information available for different areas, NMFS relied on the best 
available information and used its best professional judgment where 
data were lacking or uncertainty was great.
    To evaluate specific areas considered for designation as critical 
habitat, the CHRT considered both the use of each area by green 
sturgeon and the value of the habitat to green sturgeon. Specifically, 
the CHRT evaluated the presence and condition of the PCEs, the habitat 
functions provided, and the life stages of green sturgeon confirmed or 
most likely to occur there. To confirm the presence of the PCEs, the 
CHRT used the presence of green sturgeon, along with the best available 
habitat data. To evaluate the relative habitat value of each area, the 
CHRT considered the abundance of green sturgeon along with the best 
available data on the life stages and uses supported, the consistency 
of use, and the temporal and spatial distribution of green sturgeon 
within an area. To determine the extent to which Southern DPS green 
sturgeon used an area, and the relative value of each area to the 
Southern DPS, the CHRT used the best available tagging and genetic 
data. The CHRT's analyses and the data used are summarized in this 
final rule and described in greater detail in the final biological 
report (NMFS 2009a). In the following paragraph, we summarize the 
relevant information in response to the comments on specific coastal 
estuaries in Oregon.
    First, the presence of Southern DPS green sturgeon within coastal 
estuaries in Oregon was primarily confirmed by telemetry data and 
supported by genetic data, where available. For Winchester Bay, genetic 
tissue samples were collected between RKM 6.4 and 19.3, which is 
downstream of the head of tide in Umpqua River (head of tide = RKM 40) 
and within the boundaries of the specific area delineated for the bay 
(pers. comm. with Josh Israel, UC Davis, July 10, 2009; pers. comm. 
with Pete Baki, ODFW, July 17, 2009). It is possible that the sample 
size affected the analysis of the proportion of Southern DPS green 
sturgeon in the bay, but that does not negate the use of these data to 
confirm the presence of Southern DPS fish in this area. The CHRT 
assigned Winchester Bay a Medium conservation value rating based on 
high use of the area by green sturgeon and the presence of suitable 
habitat features (see final biological report, NMFS 2009a).
    Second, certain coastal estuaries in Oregon were excluded from the 
designation because the economic benefits of exclusion outweighed the 
conservation benefits of designation. Coastal estuaries in Oregon are 
primarily occupied by green sturgeon during the summer and contain PCEs 
(including prey resources, water quality, and migratory corridors) that 
support feeding and aggregation of subadult and adult green sturgeon. 
During the public comment period, additional data were provided by the 
ODFW regarding green sturgeon sport catch records in coastal Oregon 
estuaries. These data were used to update the data reported in the 
draft biological report (NMFS 2008b). The data were considered by the 
CHRT and incorporated into the final rule and biological report (see 
response to Comment 11). The data indicate that from 1986 to 2007, the 
largest numbers of green sturgeon were caught in Winchester Bay (n = 
1,889), Tillamook Bay (n = 279), and Nehalem Bay (n = 254), followed by 
Coos Bay and Yaquina Bay (n = 201) (ODFW 2009a, b). Southern DPS green 
sturgeon tagged in the Sacramento River and San Pablo Bay have been 
detected in Coos Bay, Winchester Bay, and Yaquina Bay (pers. comm. with 
Steve Lindley, NMFS, and Mary Moser, NMFS, February 24-25, 2008; pers. 
comm. with Dan Erickson, ODFW, September 3, 2008). The CHRT initially 
assigned a Medium conservation value to Winchester Bay, Coos Bay, 
Tillamook Bay, and Nehalem Bay, based on data indicating consistent use 
by and relatively large numbers of green sturgeon in these estuaries. 
However, the conservation value for Tillamook Bay and Nehalem Bay was 
reduced by one level to Low, because there was no evidence to confirm 
that any green sturgeon in those areas belong to the Southern DPS. 
Although Southern DPS presence has been confirmed in Yaquina Bay, the 
CHRT assigned the area a Low conservation value (NMFS 2009a). Finally, 
the estuaries at the mouths of the Siuslaw and Alsea rivers were 
assigned a Low conservation value based on relatively low numbers of 
green sturgeon recorded in the sport catch data (sport catch = 50 green 
sturgeon in Siuslaw estuary and 30 green sturgeon in Alsea estuary from 
1986 to 2007; ODFW 2009a, b). The conservation value was reduced to an

[[Page 52308]]

Ultra-low because we lack data to confirm the presence of Southern DPS 
green sturgeon in these estuaries.
    Under section 4(b)(2) of the ESA, NMFS has the discretion to 
exclude an area from the designation if the benefits of exclusion 
outweigh the benefits of designation. Tillamook Bay, Siuslaw River 
estuary, Alsea River estuary, Coos Bay, and the Rogue River estuary 
were all determined to be potentially eligible for exclusion under ESA 
section 4(b)(2) based on economic impacts. All of these, except for 
Coos Bay, were excluded based on NMFS' determination that the economic 
benefits of exclusion outweighed the conservation benefits of 
designation. Although data demonstrate that the Rogue River estuary is 
consistently used by large numbers of green sturgeon, the area was 
assigned an Ultra-Low conservation value because the best available 
data indicate that the green sturgeon observed there belong to the 
Northern DPS. Thus, the designation of critical habitat in the Rogue 
River estuary would not likely benefit the conservation of the Southern 
DPS. Coos Bay was not excluded, because the data indicate consistent 
use by relatively large numbers of green sturgeon that include Southern 
DPS fish. The CHRT determined that protection of Coos Bay as critical 
habitat is important for the conservation of green sturgeon, and 
exclusion of Coos Bay would significantly impede conservation. Based on 
the CHRT's recommendation, NMFS determined that the economic benefits 
of exclusion do not outweigh the conservation benefits of designation 
for Coos Bay and included Coos Bay in the final critical habitat 
designation. We recognize that the level of data available varies 
across areas and may affect the evaluation of these areas. We encourage 
additional studies of green sturgeon distribution in, and use of, 
coastal estuaries to inform NMFS' consultations under section 7 of the 
ESA, recovery planning and implementation, and future revisions to the 
critical habitat designation for the Southern DPS.
    Comment 16: One commenter noted that many of the coastal marine and 
estuarine areas proposed for designation as critical habitat are 
already altered habitats, wanting NMFS to recognize that routine, 
regular maintenance activities (including maintenance dredging of 
navigation channels) are conducted within these areas by the U.S. Army 
Corps of Engineers to support ongoing multi-purpose projects.
    Response: NMFS acknowledges that many of the coastal marine and 
estuarine areas proposed for designation as critical habitat contain 
habitats that have been altered by past and ongoing activities. These 
past and ongoing activities have likely affected the PCEs within each 
area, but have not degraded the PCEs such that they no longer exist 
within the areas. The continued presence and use by green sturgeon of 
each area indicate that the PCEs exist and still provide habitat 
functions to support the species. In addition, the presence of regular 
routine maintenance indicates that the PCEs within the coastal marine 
and estuarine areas may require special management considerations or 
protection.
    Comment 17: One commenter noted that the proposed rule incorrectly 
stated that green sturgeon present in estuaries of the Eel, Klamath/
Trinity, and Rogue rivers are believed to belong to the Northern DPS, 
based on the fact that these are spawning rivers for the Northern DPS 
(73