[Federal Register: June 14, 2004 (Volume 69, Number 113)]
[Proposed Rules]
[Page 33101-33179]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr14jn04-33]
[[Page 33101]]
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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 Species: Proposed Listing Determinations for
27 ESUs of West Coast Salmonids; Proposed Rule
[[Page 33102]]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
50 CFR Parts 223 and 224
[Docket No. 040525161-4161-01; I.D. No. 052104F]
RIN 0648-AR93
Endangered and Threatened Species: Proposed Listing
Determinations for 27 ESUs of West Coast Salmonids
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Proposed rule; request for comments.
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SUMMARY: NMFS has completed comprehensive status reviews for 26 West
Coast salmon (chum, Oncorhynchus keta; coho, O. kisutch, O. nerka;
chinook, O. tshawytscha; pink, O. gorbuscha) and O. mykiss (inclusive
of anadromous steelhead and resident rainbow trout) Evolutionarily
Significant Units (ESUs) previously listed as threatened and endangered
species under the Endangered Species Act (ESA), as well as one ESU that
was designated as a candidate species, for a total of 27 ESUs.
Following a September 2001 U.S. District Court ruling that rejected how
NMFS treats hatchery stocks in its listing determinations, the agency
received several petitions seeking to delist, or to redefine and list,
17 salmon and steelhead ESUs on the basis of the Court's ruling. In
response to these petitions NMFS initiated status reviews for 16 of
these ESUs, and elected to conduct status reviews for an additional 11
ESUs. Based on these reviews, NMFS is now issuing a proposed rule to
list four ESUs as endangered and 23 ESUs as threatened. Collectively,
these 27 ESUs include 162 artificial propagation programs. NMFS also
proposes amending existing protective regulations, promulgated under
section 4(d) of the ESA, for threatened ESUs.
DATES: Comments must be received no later than 5 p.m. P.S.T. on
September 13, 2004. (See ADDRESSES.) NMFS will announce the dates and
locations of public hearings in California, Oregon, Washington, and
Idaho in a separate Federal Register notice.
ADDRESSES: Comments should be submitted to Chief, Protected Resources
Division, NMFS, 525 NE Oregon Street--Suite 500, Portland, OR 97232-
2737. Comments on this proposed rule may be submitted by e-mail. The
mailbox address for providing e-mail comments is salmon.nwr@noaa.gov.
Include in the subject line of the e-mail comment the following
document identifier: 040525161-4161-01. Comments may also be submitted
via facsimile (fax) to 503-230-5435, or via the Internet at http://www.nmfs.noaa.gov/ibrm.
Comments may also be submitted electronically
through the Federal e-Rulemaking portal: http://www.regulations.gov.
FOR FURTHER INFORMATION CONTACT: For further information regarding this
proposed rule contact Garth Griffin, NMFS, Northwest Region, (503) 231-
2005; Craig Wingert, NMFS, Southwest Region, (562) 980-4021; or Marta
Nammack, NMFS, Office of Protected Resources, (301) 713-1401.
SUPPLEMENTARY INFORMATION:
Organization of This Proposed Rule
This Federal Register notice describes the proposed listing
determinations for 27 ESUs of West Coast salmon and O. mykiss under the
ESA. The pages that follow review the information considered in
formulating the proposed listing determinations. To assist the reader,
this section briefly outlines the organization and content of this
notice. Section headings listed in this outline are denoted in bold
text, and subheadings in italics in the body of the notice.
I. Review of necessary Background information
Statutory basis for Listing Species Under the
Endangered Species Act
NMFS' Previous Federal ESA Actions Related to West
Coast Salmonids
NMFS' Past Practice in Pacific Salmonid ESA Listing
Determinations
Recent court decisions (Alsea Valley Alliance v. Evans)
and a Summary of Petitions seeking listing/delisting actions that
precipitated the Initiation of Coast-wide ESA Status Reviews for
Pacific Salmonids
Overview of the Life History of West Coast Salmonids
II. Consideration of specific issues in Assessing Extinction Risk
for Pacific Salmonids
Consideration of Artificial Propagation in Listing
Determinations
Consideration of Resident O. mykiss Populations in
Listing Determinations
Consideration of Recent Ocean Conditions in Listing
Determinations
III. Treatment of the four listing determination steps for each ESU
under review
(1) Determination of ``Species'' under the ESA
(2) Review of the best available information for Updated
Viability Assessments of ESUs
(3) Evaluation of Efforts Being Made to Protect West Coast
Salmon and O. mykiss
(4) Proposed Listing Determinations of ``threatened,''
``endangered,'' or ``not warranted,'' based on the foregoing
information
IV. Take Prohibitions and Protective Regulations:
Overview of the take prohibitions and protective
regulations that presently apply to listed ESUs
Description of a proposed amendment to these protective
regulations
V. Summary of agency efforts in designating Critical Habitat for
listed salmon and O. mykiss ESUs
VI. Description of the Public Comments Solicited and other
opportunities for public involvement in this rulemaking process
VII. Description of the Classification, NMFS' compliance with
various laws and executive orders with respect to this proposed
rulemaking (e.g., National Environmental Policy Act, Regulatory
Flexibility Act)
VIII. Description of proposed amendments to the Code of Federal
Regulations. This section itemizes the specific changes to federal
law being proposed based on the foregoing information
Proposed amendments to the list of threatened and
endangered species
Proposed amendment to the protective regulations for
threatened West Coast salmon and O. mykiss
Background
Listing Species Under the Endangered Species Act
NMFS is responsible for determining whether species, subspecies, or
distinct population segments (DPSs) of Pacific salmon and steelhead are
threatened or endangered under the Endangered Species Act (ESA) (16
U.S.C. 1531 et seq). To be considered for listing under the ESA, a
group of organisms must constitute a ``species,'' which is defined in
section 3 of the ESA to include ``any subspecies of fish or wildlife or
plants, and any distinct population segment [emphasis added] of any
species of vertebrate fish or wildlife which interbreeds when mature.''
In this notice, NMFS is proposing listing determinations for DPSs of
Pacific salmon and O. mykiss. NMFS has determined that, to qualify as a
DPS, a Pacific salmon or O. mykiss population must be substantially
reproductively isolated from other conspecific populations and
represent an important component in the evolutionary legacy of the
biological species. A population meeting these criteria is considered
to be an ESU (56 FR 58612; November 20, 1991). In its listing
determinations for Pacific salmonids under the ESA, NMFS has treated an
ESU as constituting a DPS, and hence a ``species,'' under the ESA. The
terms ``DPS'' and ``ESU'' are used synonymously in this document.
[[Page 33103]]
Section 3 of the ESA defines an endangered species as ``any species
which is in danger of extinction throughout all or a significant
portion of its range'' and a threatened species as one ``which is
likely to become an endangered species within the foreseeable future
throughout all or a significant portion of its range.'' The statute
lists factors that may cause a species to be threatened or endangered
(ESA section 4(a)(1)): (a) The present or threatened destruction,
modification, or curtailment of its habitat or range; (b)
overutilization for commercial, recreational, scientific, or
educational purposes; (c) disease or predation; (d) the inadequacy of
existing regulatory mechanisms; or (e) other natural or manmade factors
affecting its continued existence.
Section 4(b)(1)(A) of the ESA requires NMFS to make listing
determinations based solely on the best scientific and commercial data
available after conducting a review of the status of the species and
after taking into account efforts being made to protect the species (in
this proposed rule the term ``status'' is used in the statutory
context, referring to the ESA listing status of ``threatened,''
``endangered,'' or listing not warranted). Accordingly, NMFS follows
three steps in making its listing determinations for Pacific salmon and
O. mykiss: (1) NMFS first determines whether a population or group of
populations constitutes an ESU, that is, whether the population(s) are
a ``species'' within the meaning of the ESA; (2) NMFS then determines
the viability of the ESU and the factors that have led to its decline;
and (3) NMFS assesses efforts being made to protect the ESU,
determining if these efforts are adequate to mitigate threats to the
species. Based on the foregoing information and the statutory listing
criteria, NMFS then proposes a listing determination of whether the
species is threatened or endangered in a significant portion of its
range.
Previous Federal ESA Actions Related to West Coast Salmonids
Pacific salmon and O. mykiss ESUs in California and the Pacific
Northwest have suffered broad declines over the past hundred years. (In
this document the scientific name ``O. mykiss'' refers to both
anadromous steelhead and resident rainbow trout life-history forms).
NMFS has conducted several ESA status reviews and status review updates
for six biological species of Pacific salmon and O. mykiss in
California, Oregon, Washington, and Idaho, identifying 51 ESUs and
listing 26 of these ESUs to date. Table 1 summarizes the previous NMFS
scientific reviews of the viability of salmon and steelhead and the ESA
listing determinations for the 27 ESUs addressed in this proposed rule.
Table 1.--Summary of Previous ESA Listing Actions Related to the 27 Evolutionarily Significant Units of West
Coast Salmon and Oncorhynchus Mykiss Under Review
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Previous
Evolutionarily Significant Unit Current endangered Year Previous ESA listing scientific
(ESU) species act (ESA) listed determinations--Federal viability reviews
status Register citations and updates
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........ 56 FR 58619; 11/20/1991
(Final rule).
Snake River sockeye ESU......... Endangered........ 1991 56 FR 14055; 04/05/1991 NMFS 1991a
(Proposed rule).
........ 64 FR 14528; 03/25/1999 NMFS 1998d
(Final rule).
Ozette Lake sockeye ESU......... Threatened........ 1999 63 FR 11750; 03/10/1998 NMFS 1997f
(Proposed rule).
........ 59 FR 440; 01/01/1994
(Final rule).
........ 57 FR 27416; 06/19/1992
(Proposed rule).
........ 55 FR 49623; 11/30/1990
(Final rule).
........ 55 FR 12831, 04/06/1990
(Emergency rule).
........ 55 FR 102260; 03/20/1990
(Proposed rule).
........ 54 FR 10260; 08/04/1989
(Emergency rule).
Sacramento River winter-run Endangered........ 1994 52 FR 6041; 02/27/1987
chinook ESU. (Final rule).
........ 64 FR 50394; 09/16/1999 NMFS 1998b.
(Final rule).
Central Valley spring-run Threatened........ 1999 63 FR 11482; 03/09/1998 NMFS 1999d.
chinook ESU. (Proposed rule).
........ 64 FR 50394; 09/16/1999 NMFS 1998b.
(Final rule).
California Coastal chinook ESU.. Threatened........ 1999 63 FR 11482; 03/09/1998 NMFS 1999d.
(Proposed rule).
........ .......................... NMFS 1998b.
........ 64 FR 14308; 03/24/99 NMFS 1998e.
(Final rule).
Upper Willamette River chinook Threatened........ 1999 63 FR 11482; 03/09/1998 NMFS 1999c.
ESU. (Proposed rule).
........ .......................... NMFS 1998b.
........ 64 FR 14308; 03/24/99 NMFS 1998e.
(Final rule).
Lower Columbia River chinook ESU Threatened........ 1999 63 FR 11482; 03/09/1998 NMFS 1999c.
(Proposed rule).
Upper Columbia River spring-run Endangered........ 1999
chinook ESU.
........ NMFS 1998b.
........ 64 FR 14308; 03/24/99 NMFS 1998e.
(Final rule).
........ 63 FR 11482; 03/09/1998 NMFS 1999c.
(Proposed rule).
[[Page 33104]]
........ NMFS 1998b.
........ 64 FR 14308; 03/24/99 NMFS 1998e.
(Final rule).
Puget Sound chinook ESU......... Threatened......... 1999 63 FR 11482; 03/09/1998 NMFS 1999c.
(Proposed rule).
........ 63 FR 1807; 0/12/1998
(Proposed withdrawn).
........ 59 FR 66784; 12/28/1994
(Proposed rule).
........ 59 FR 42529; 08/18/1994
(Emergency rule).
........ 57 FR 23458; 06/03/1992
(Correction).
........ 57 FR 14653; 04/22/1992 NMFS 1991c.
(Final rule).
Snake River fall-run chinook ESU Threatened......... 1992 56 FR 29547; 06/27/1991 NMFS 1999d.
(Proposed rule).
........ 63 FR 1807; 0/12/1998
(Proposed withdrawn).
........ 59 FR 66784; 12/28/1994
(Proposed rule).
........ 59 FR 42529; 08/18/1994
(Emergency rule).
........ 57 FR 23458; 06/03/1992
(Correction).
........ 57 FR 34639; 04/22/1992 NMFS 1991b.
(Final rule).
Snake River spring/summer-run Threatened......... 1992 56 FR 29542; 06/27/1991 NMFS 1998b.
chinook ESU. (Proposed rule).
........ 61 FR 56138;- 10/31/1996 Bryant 1994
(Final rule).
Central California Coast coho
ESU.
Threatened......... 1996 60 FR 38011; 07/25/1995 NMFS 1995a.
(Proposed rule).
........ NMFS 1997a.
........ NMFS 1996c.
........ 62 FR 24588; 05/06/1997 NMFS 1996e.
(Final rule).
Southern Oregon/Northern Threatened......... 1997 60 FR 38011; 07/25/1995 NMFS 1995a.
California Coast coho ESU. (Proposed rule).
........ 69 FR 19975; 04/15/2004
(Candidate list).
........ 63 FR 42587; 08/10/1998 NMFS 1997a.
(Final rule).
........ 62 FR 24588; 05/06/1997 NMFS 1996b.
(Proposed withdrawn).
........ 61 FR 56138; 10/31/1996 (6 NMFS 1996d.
mo. extension).
Oregon Coast coho ESU........... Threatened*........ 1998 60 FR 38011; 07/25/1995 NMFS 1995a.
(Proposed rule).
Lower Columbia River coho ESU... Candidate.......... 1995 69 FR 19975; 04/15/2004 NMFS 1996e.
(Candidate list).
........ NMFS 1995a.
........ 60 FR 38011; 07/25/1995 NMFS 1991a.
(Not warranted).
........ NMFS 1997e.
........ 64 FR 145008; 03/25/1999 NMFS 1999b.
(Final rule) 3.
Columbia River chum ESU......... Threatened......... 1999 63 FR 11774; 03/10/1998 NMFS 1999c.
(Proposed rule).
........ NMFS 1996d.
........ NMFS 1997e.
........ 64 FR 14508; 03/25/1999 NMFS 1999b.
(Final rule).
Hood Canal summer-run chum ESU.. Threatened......... 1999 63 FR 11774; 03/10/1998 NMFS 1999c.
(Proposed rule).
........ 67 FR 21568; 05/01/2002
(Redefinition of ESU).
........ 62 FR 43937; 08/18/1997 NMFS 1996b.
(Final rule).
[[Page 33105]]
Southern California steelhead Endangered......... 1997 61 FR 41541; 08/09/1996 NMFS 1997b.
ESU. (Proposed rule).
........ 62 FR 43937; 08/18/1997 NMFS 1996b.
(Final rule).
South-Central California Coast Threatened......... 1997 61 FR 41541; 08/09/1996 NMFS 1997b.
steelhead ESU. (Proposed rule).
........ 62 FR 43937; 08/18/1997 NMFS 1996b.
(Final rule).
Central California Coast Threatened......... 1997 61 FR 41541; 08/09/1996 NMFS 1997b.
steelhead ESU. (Proposed rule).
........ NMFS 1996b.
........ NMFS 1997b.
........ 63 FR 13347; 03/19/1998 NMFS 1997c.
(Final rule).
........ 62 FR 43974; 08/18/1997 (6 NMFS 1997d.
mo. extension).
California Central Valley Threatened......... 1998 61 FR 41541; 08/09/1996 NMFS 1998a.
steelhead ESU. (Proposed rule).
........ 65 FR 36074; 06/07/2000
(Final rule).
........ 65 FR 6960; 02/11/2000 NMFS 1996b.
(Proposed rule).
........ 63 FR 13347; 03/19/1998 NMFS 1997c.
(Not Warranted).
........ 62 FR 43974; 08/18/1997 (6 NMFS 1998a.
mo. extension).
Northern California steelhead Threatened......... 2000 61 FR 41541; 08/09/1996 NMFS 2000.
ESU. (Proposed rule).
........ 64 FR 14517; 03/25/1999 NMFS 1996b.
(Final rule).
........ 63 FR 11798; 03/10/1998 NMFS 1997d.
(Proposed rule).
Upper Willamette River steelhead Threatened......... 1999 62 FR 43974; 08/18/1997 (6 NMFS 1999a.
ESU. mo. extension).
........ 61 FR 41541; 08/09/1996 NMFS 1999c.
(Proposed rule).
........ NMFS 1996b.
........ 63 FR 13347; 03/19/1998 NMFS 1997c.
(Final rule).
........ 62 FR 43974; 08/18/1997 (6 NMFS 1997d.
mo. extension).
Lower Columbia River steelhead Threatened......... 1998 61 FR 41541; 08/09/1996 NMFS 1998a.
ESU. (Proposed rule).
........ 64 FR 14517; 03/25/1999 NMFS 1996b.
(Final rule).
........ 63 FR 11798; 03/10/1998 NMFS 1997d.
(Proposed rule).
........ 62 FR 43974; 08/18/1997 (6 NMFS 1999a.
mo. extension).
Middle Columbia River steelhead Threatened......... 1999 61 FR 41541; 08/09/1996 NMFS 1999c.
ESU. (Proposed rule).
........ 62 FR 43937; 08/18/1997 NMFS 1996b.
(Final rule).
Upper Columbia River steelhead Endangered......... 1997 61 FR 41541; 08/09/1996 NMFS 1997b.
ESU. (Proposed rule).
........ 62 FR 43937; 08/18/1997 NMFS 1996b.
(Final rule).
Snake River Basin steelhead ESU. Threatened......... 1997 61 FR 41541; 08/09/1996 NMFS 1997b.
(Proposed rule).
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*But see Alsea Valley Alliance v. Evans, 358 F.3d 1181 (9th Cir. Feb. 24, 2004).
[[Page 33106]]
Past Practice in Pacific Salmonid ESA Listing Determinations
In past ESA listing determinations, NMFS followed the four step
approach described above. In the past, NMFS focused on whether the
naturally spawned fish are, by themselves, self-sustaining in their
natural ecosystem over the long term. NMFS listed as ``endangered''
those ESUs whose naturally spawned populations were found to have a
present high risk of extinction, and listed as ``threatened'' those
ESUs whose naturally spawned populations were found likely to become
endangered in the foreseeable future (that is, whose present risk of
extinction was not high, but whose risk of extinction was likely to
become high within a foreseeable period of time).
In its listing determinations, NMFS did not explicitly consider the
contribution of the hatchery fish to the overall viability of the ESU,
or whether the presence of hatchery fish within the ESU might have the
potential for reducing the risk of extinction of the ESU or the
likelihood that the ESU would become endangered in the foreseeable
future. (The listing of Snake River fall chinook, however, is an
exception. See 57 FR 14653; April 22, 1992.) NMFS frequently evaluated
artificial propagation only as a factor in the decline of the naturally
spawned populations within an ESU.
For each ESU where hatchery fish were present, NMFS reviewed the
associated hatchery populations to determine how closely related the
hatchery populations were to the naturally spawned populations. This
review focused on the origin of the hatchery fish and their similarity
to locally adapted naturally spawned fish. Factors included in this
consideration were: Genetic, life history, and habitat use
characteristics; the degree to which the characteristics of the wild
population may have been altered over time; and other factors that
would affect the biological usefulness of hatchery fish for recovery.
Since 1993, NMFS has applied an interim policy on how it will
consider artificial propagation in the listing and recovery of Pacific
salmon and steelhead under the ESA (58 FR 17573, April 5, 1993). The
1993 policy provided guidance on the use of artificial propagation to
assist in the conservation of these listed species and to help avoid
additional species listings. The policy also provided guidance for
evaluating artificial propagation in section 7 consultation, section 10
permitting, and recovery planning pursuant to the ESA.
When NMFS determined that an ESU should be listed as threatened or
endangered, it applied its interim artificial propagation policy for
Pacific salmon and steelhead. That policy provided that hatchery salmon
and steelhead found to be part of the ESU would not be listed under the
ESA unless they were found to be essential for recovery (i.e., if NMFS
determined that the hatchery population contained a substantial portion
of the genetic diversity remaining in the ESU). The result of this
policy was that a listing determination for an ESU depended solely upon
the relative health of the naturally spawning component of the ESU. In
most cases, hatchery fish within the ESUs were not relied upon to
contribute to recovery, and therefore were not listed.
In addition, resident O. mykiss populations (i.e., rainbow trout)
included in steelhead ESUs were not listed when it was determined that
the steelhead warranted listing because the U.S. Fish and Wildlife
Service (FWS) retains ESA jurisdiction over resident rainbow trout.
Alsea Valley Alliance v. Evans
In September 2001, the U.S. District Court in Eugene, Oregon, in
Alsea Valley Alliance v. Evans (161 F. Supp. 2d 1154, D. Oreg. 2001;
Alsea decision), set aside NMFS' 1998 ESA listing of Oregon Coast coho
salmon (63 FR 42587; 08/10/1998). The Court ruled that the ESA does not
allow NMFS to list a subset of an ESU, and that NMFS had improperly
excluded stocks from the listing once it had decided that certain
hatchery stocks were part of the ESU. Although the Court's ruling
affected only one ESU, the interpretive issue raised by the ruling
called into question nearly all of NMFS' Pacific salmonid listing
determinations. The Court struck down the 1998 final rule listing
Oregon coast coho as a threatened species, thus removing the ESU from
the protections of the ESA. The Court remanded the case to NMFS for
reconsideration consistent with the Alsea decision. NMFS did not
contest the Court's ruling and informed the Court it would comply. In
November 2001 intervenors appealed the Court's ruling to the U.S. Ninth
Circuit Court of Appeals. Pending resolution of the appeal, the Ninth
Circuit stayed the District Court's remand order and invalidation of
the 1998 listing. While the stay was in place, the Oregon Coast coho
ESU was again afforded the protections of the ESA (Alsea Valley
Alliance v. Evans, 9th Circuit appeal, No. 01-36071, December 14,
2001). On February 24, 2004, the Appeals Court dismissed the appeal,
and dissolved its stay of the District Court's ruling in Alsea.
Following the District Court's ruling in the Alsea case, NMFS
received several petitions (summarized below) addressing 17 listed
salmonid ESUs, including five steelhead ESUs. These petitions cited the
Alsea ruling and focused on NMFS' past practice of excluding certain
ESU hatchery stocks from listing protection. Various litigants have
also challenged the failure to list resident populations included in
threatened and endangered steelhead ESUs. The anadromous form of O.
mykiss (i.e., steelhead) is presently under NMFS' jurisdiction, while
the resident freshwater forms, usually called ``rainbow'' or
``redband'' trout, are under FWS jurisdiction. In Environmental Defense
Center et al. v. Evans et al. (EDC v. Evans, SACV-00-1212-AHS (EEA)),
the plaintiffs argue that NMFS failed to include resident populations
in the endangered listing of the Southern California steelhead ESU (62
FR 43937; August 18, 1997). In Modesto Irrigation District et al. v.
Evans et al. (MID v. Evans, CIV-F-02-6553 OWW DLB (E.D. Cal)), the
plaintiffs seek to invalidate NMFS' 1997 threatened listing of the
Central Valley California steelhead ESU (63 FR 13347; March 19, 1998)
for failing to list hatchery and resident populations identified as
part of the ESU. This same factual situation is found in all listed
steelhead ESUs; the listings do not include hatchery and/or resident
populations considered to be part of the ESUs. For the proposed listing
determinations detailed in this proposed rule to be compliant with the
Court's ruling in the Alsea case, all populations or stocks (natural,
hatchery, resident, etc.) included in an ESU must be listed if it is
determined that the ESU is threatened or endangered under the ESA.
Summary of Petitions
Following the ruling in the Alsea case, NMFS received several
petitions seeking to delist, or to redefine and list, ESUs of Pacific
salmon and steelhead. The petitioners made reference to the Alsea
decision in arguing for NMFS to reconsider the listing status for
certain ESUs. Between September 2001 and April 2002 NMFS received eight
separate petitions addressing a total of 17 listed salmon and steelhead
ESUs.
On September 19, 2001, NMFS received a petition from Interactive
Citizens United to delist coho salmon in Siskiyou County, California.
These fish are part of a larger ESU of Southern Oregon/Northern
California Coast coho
[[Page 33107]]
salmon. NMFS determined that the Interactive Citizens United petition
was not warranted, finding that it failed to present substantial
scientific or commercial information to suggest that delisting may be
warranted (67 FR 6215; February 11, 2002). On March 18, 2002, NMFS
received a duplicate petition from the California State Grange to
delist coho salmon in Siskiyou County, California. NMFS made a negative
finding on the California State Grange petition (67 FR 40679; June 13,
2002), for the same reasons as for its finding on the Interactive
Citizens United petition.
During October 2001, NMFS received 5 additional delisting petitions
addressing 15 ESUs. On October 22, 2001, NMFS received a petition from
the Washington State Farm Bureau, on the behalf of a coalition of
agricultural organizations in Washington State, to delist 12 Pacific
salmon ESUs including: One sockeye ESU (the endangered Snake River
sockeye ESU); six chinook ESUs (the threatened Puget Sound, Snake River
spring/summer, Snake River fall, and Lower Columbia River chinook ESUs,
as well as the endangered Upper Columbia River spring-run chinook ESU);
two chum ESUs (the threatened Hood Canal summer-run and Columbia River
chum ESUs); and four steelhead ESUs (the threatened Lower Columbia
River, Middle Columbia River, and Snake River steelhead ESUs, as well
as the endangered Upper Columbia River steelhead ESU). On October 17,
2001, NMFS received a petition on behalf of the Columbia-Snake River
Irrigators' Association to delist seven Pacific salmon ESUs including:
One sockeye ESU (the endangered Snake River sockeye ESU); three chinook
ESUs (the threatened Snake River fall and Snake River spring/summer
chinook ESUs, as well as the endangered Upper Columbia River spring-run
chinook ESU); and three steelhead ESUs (the threatened Middle Columbia
River and Snake River steelhead ESUs, as well as the endangered Upper
Columbia River steelhead ESUs). On October 17, 2001, NMFS received a
petition on behalf of the Kitsap Alliance of Property Owners and the
Skagit County Cattlemen's Association to delist the threatened Puget
Sound chinook and Hood Canal summer-run chum ESUs. On October 23, 2001,
NMFS received a petition on behalf of seven individuals to delist the
threatened Southern Oregon/Northern California Coast coho ESU. On
October 24, 2001, NMFS received a petition on behalf of the Greenberry
Irrigation District to delist the threatened Upper Willamette River
chinook and steelhead ESUs. NMFS determined that these petitions, in
light of the Alsea decision, presented substantial scientific and
commercial information indicating that delisting may be warranted for
14 of the 15 petitioned ESUs (67 FR 6215; February 11, 2002). In the
case of the Snake River sockeye ESU, NMFS determined that the
Washington State Farm Bureau and Columbia-Snake River Irrigators'
Association petitions failed to present substantial scientific and
commercial information that delisting may be warranted.
On March 14, 2002, NMFS received a petition from the Central Coast
Forest Association to delist the threatened Central California Coast
coho salmon ESU. On April 29, 2002, NMFS received two petitions from
Trout Unlimited and several co-petitioners seeking to redefine and list
a total of 15 ESUs including: Six chinook ESUs (the threatened Puget
Sound, Upper Willamette River, Snake River spring/summer, Snake River
fall, and Lower Columbia River chinook ESUs, as well as the endangered
Upper Columbia River spring-run chinook ESU); two chum ESUs (the
threatened Hood Canal summer and Columbia River chum ESUs); two coho
ESUs (the threatened Oregon Coast and Southern Oregon/Northern
California Coast coho ESUs); and five steelhead ESUs (the threatened
Upper Willamette River, Snake River, Middle Columbia River, and Lower
Columbia River steelhead ESUs, as well as the endangered Upper Columbia
River steelhead ESU). The two Trout Unlimited petitions sought to
redefine and list these ESUs as including only natural fish. NMFS
determined that these three petitions presented substantial scientific
and commercial information to suggest that the petitioned actions may
be warranted (67 FR 48601; July 25, 2002).
The ESA requires that, as a consequence of accepting the above
petitions, NMFS promptly commence a review of the species' status and
make a finding within 12 months after receiving the petition, whether
the petitioned action is warranted (ESA section 4(b)(3)). There are 16
ESUs (described above for the various accepted petitions) for which
NMFS has statutory deadlines for the completion of ESA status reviews
and listing determinations: Seven chinook ESUs (the Upper Willamette
River, Lower Columbia River, Upper Columbia River spring-run, Puget
Sound, Snake River fall-run, and Snake River spring/summer-run chinook
ESUs); three coho ESUs (the Central California Coast, Southern Oregon/
Northern California Coast, and Oregon Coast coho ESUs); two chum ESUs
(the Columbia River and Hood Canal summer-run chum salmon ESUs); and
five steelhead ESUs (the Upper Willamette River, Lower Columbia River,
Middle Columbia River, Upper Columbia River, and Snake River Basin
steelhead ESUs).
Initiation of Coast-Wide ESA Status Reviews
The ESUs addressed in this proposed rule include 26 previously
listed West Coast salmon and steelhead ESUs, and one ESU designated as
a candidate species (the Lower Columbia coho ESU). As part of its
response to the ESA interpretive issues raised by the ruling in the
Alsea case, NMFS elected to initiate status reviews for a total of 27
ESUs: 11 ESUs in addition to the 16 ESUs for which it had accepted
delisting/listing petitions. As announced in a Federal Register notice
published on February 11, 2002 (67 FR 6215), these 11 additional ESUs
are: One sockeye ESU (the threatened Ozette Lake sockeye ESU); three
chinook ESUs (the endangered Sacramento River winter-run chinook ESU,
as well as the threatened Central Valley spring-run and California
coastal chinook ESUs); three coho ESUs (the threatened Central
California Coast and Oregon Coast coho ESUs, as well as the candidate
Lower Columbia River coho ESU); and four steelhead ESUs (the threatened
South-Central California Coast, Central California Coast, California
Central Valley, and Northern California steelhead ESUs) (as noted
above, NMFS subsequently accepted petitions addressing the Central
California and Oregon Coast coho ESUs). On December 31, 2002, NMFS
announced that it would also elect to review the ESA listing status of
Snake River sockeye and Southern California steelhead ESUs (67 FR
79898). NMFS elected to conduct these additional status reviews to
address any errors in the listing determinations brought to light by
the Alsea decision, as well as to consider the most recent information
available for these ESUs. At the time of the Alsea decision, NMFS was
conducting a status review for the candidate Lower Columbia River coho
ESU in response to a July 24, 2000, petition from Oregon Trout and co-
petitioners (see 65 FR 66221, November 3, 2000). Accordingly, NMFS
elected to include the Lower Columbia River coho ESU in this status
review effort for the other 26 ESUs. NMFS did not elect to conduct
status reviews for any other candidate ESUs (e.g., the Puget Sound/
Strait of Georgia coho, Central Valley fall and late-fall chinook, and
Oregon Coast steelhead
[[Page 33108]]
ESUs) or ESUs that NMFS previously determined did not warrant ESA
listing.
NMFS solicited information to ensure that the review of the ESA
status for the 27 ESUs under review was based on the best available and
most recent scientific and commercial data. Following an initial 60-day
public comment period concerning 25 of the ESUs, which commenced on
February 11, 2002 (67 FR 6215), NMFS re-opened the public comment
period for an additional 30 days on June 13, 2002 (67 FR 40679). A 60-
day public comment period was also opened concerning 16 petitioned ESUs
with the published findings on the Central Coast Forest Association and
Trout Unlimited et al. petitions on July 25, 2002 (67 FR 48601).
Information and comment was solicited during an additional 60-day
public comment period when NMFS announced that it would also be
reviewing the status of the Snake River sockeye and Southern California
steelhead ESUs (67 FR 79898; December 31, 2002). In this latter public
comment period NMFS specifically requested information concerning
resident O. mykiss populations in the 10 steelhead ESUs under review
(67 FR at 79900).
Life History of West Coast Salmonids
Pacific salmon and steelhead are anadromous fish, meaning adults
migrate from the ocean to spawn in freshwater lakes and streams where
their offspring hatch and rear prior to migrating to the ocean to
forage until maturity. The migration and spawning times vary
considerably among and within species and populations (Groot and
Margolis, 1991). At spawning, adults pair to lay and fertilize
thousands of eggs in freshwater gravel nests or ``redds'' excavated by
females. Depending on lake/stream temperatures, eggs incubate for
several weeks to months before hatching as ``alevins'' (a larval life
stage dependent on food stored in a yolk sac). Following yolk sac
absorption, alevins emerge from the gravel as young juveniles called
``fry'' and begin actively feeding. Depending on the species and
location, juveniles may spend from a few hours to several years in
freshwater areas before migrating to the ocean. The physiological and
behavioral changes required for the transition to salt water result in
a distinct ``smolt'' stage in most species. Enroute to the ocean the
juveniles may spend from a few days to several weeks in the estuary,
depending on the species. The highly productive estuarine environment
is an important feeding and acclimation area for juveniles preparing to
enter marine waters.
Juveniles and subadults typically spend from 1 to 5 years foraging
over thousands of miles in the North Pacific Ocean before returning to
freshwater to spawn. Some species, such as coho and chinook salmon,
have precocious life-history types (primarily male fish) that mature
and spawn after only several months in the ocean. Spawning migrations
known as ``runs'' occur throughout the year, varying in time by species
and location. Most adult fish return or ``home'' with great fidelity to
spawn in their natal stream, although some do stray to non-natal
streams. Salmon species die after spawning, while anadromous O. mykiss
may return to the ocean and make repeat spawning migrations.
Below we provide brief descriptions of the life histories of the
Pacific salmonid species under review. More complete descriptions can
be found in the status review documents listed in Table 1.
West Coast Sockeye Salmon
Spawning populations of sockeye salmon range from the Columbia
River in the south to the Noatak River in the north in North America,
and from Hokkaido, Japan in the south to the Anadyr River in the north
in Asia (Atkinson et al., 1967; Burgner, 1991). Most sockeye salmon
spawn in either inlet or outlet streams of lakes or in lakes
themselves. The offspring of these ``lake-type'' sockeye salmon use
lake environments for juvenile rearing for 1 to 3 years and then
migrate to sea, returning to the natal lake system to spawn after
spending 1 to 4 years in the ocean.
Certain self-perpetuating, nonanadromous populations of O. nerka
that become resident in lake environments over long periods of time are
called kokanee in North America. Genetic differentiation among sockeye
salmon and kokanee populations indicates that kokanee have arisen from
sockeye salmon on multiple independent occasions, and that kokanee and
sockeye salmon may have either overlapping or distinct distributions.
Numerous studies (reviewed in Gustafson et al., 1997) indicate that
sockeye salmon and kokanee exhibit a suite of heritable differences in
morphology, early development rate, seawater adaptability, growth and
maturation that appear to be divergent adaptations that have arisen
from different selective regimes associated with anadromous vs.
nonanadromous life histories. These studies also provide evidence that
overlapping populations of sockeye salmon and kokanee can be both
genetically distinct and reproductively isolated (see citations in
Gustafson et al., 1997). Occasionally, a proportion of juveniles in an
anadromous sockeye population will remain in the rearing lake
environment throughout life and will be observed on the spawning
grounds together with their anadromous siblings. Ricker (1938) first
used the terms ``residual sockeye'' and ``residuals'' to refer to these
resident, non-migratory progeny of anadromous sockeye salmon.
West Coast Chinook Salmon
Chinook salmon, also commonly referred to as king, spring, quinnat,
Sacramento, California, or tyee salmon, is the largest of the Pacific
salmon (Myers et al., 1998). The species historically ranged from the
Ventura River in California to Point Hope, Alaska, and in northeastern
Asia from Hokkaido, Japan to the Anadyr River in Russia (Healey, 1991).
Additionally, chinook salmon have been reported in the Mackenzie River
area of Northern Canada (McPhail and Lindsey, 1970). Chinook salmon
exhibit diverse and complex life history strategies (Healey, 1986). Two
generalized freshwater life-history types were initially described by
Gilbert (1912): ``stream-type'' chinook salmon reside in freshwater for
a year or more following emergence, whereas ``ocean-type'' chinook
salmon migrate to the ocean predominately within their first year.
Of the two life history types, ocean-type chinook salmon exhibit
the most varied and flexible life-history trajectories. Ocean-type
chinook salmon juveniles emigrate to the ocean as fry, subyearling
juveniles (during their first spring or fall), or as yearling juveniles
(during their second spring), depending on environmental conditions.
Ocean-type chinook salmon also undertake distinct, coastally oriented,
ocean migrations. The timing of the return to freshwater and spawning
is closely related to the ecological characteristics of a population's
spawning habitat. Five different run times are expressed by different
ocean-type chinook salmon populations: Spring, summer, fall, late-fall,
and winter. In general, early run times (spring and summer) are
exhibited by populations that use high spring flows to access headwater
or interior regions. Ocean-type populations within a basin that express
different run times appear to have evolved from a common source
population.
Stream-type populations appear to be nearly obligate yearling
outmigrants (although some 2-year-old smolts have been identified),
undertake extensive off-shore ocean migrations, and
[[Page 33109]]
generally return to freshwater as spring-or summer-run fish. Stream-
type populations are found in northern British Columbia and Alaska, and
in the headwater regions of the Fraser River and Columbia River Basin
inland tributaries.
West Coast Coho Salmon
Coho salmon is a widespread species of Pacific salmon, occurring in
most major river basins around the Pacific Rim from Monterey Bay,
California, north to Point Hope, Alaska, through the Aleutians, and
from the Anadyr River south to Korea and northern Hokkaido, Japan
(Laufle et al., 1986). From central British Columbia south, the vast
majority of coho salmon adults are 3-year-olds, having spent
approximately 18 months in fresh water and 18 months in salt water
(Gilbert, 1912; Pritchard, 1940; Sandercock, 1991). The primary
exceptions to this pattern are ``jacks,'' sexually mature males that
return to freshwater to spawn after only 5 to 7 months in the ocean.
However, in southeast and central Alaska, the majority of coho salmon
adults are 4-year-olds, having spent an additional year in fresh water
before going to sea (Godfrey et al., 1975; Crone and Bond, 1976). The
transition zone between predominantly 3-year-old and 4-year-old adults
occurs somewhere between central British Columbia and southeast Alaska.
West Coast coho smolts typically leave freshwater in the spring
(April to June) and re-enter freshwater when sexually mature from
September to November, and spawn from November to December and
occasionally into January (Sandercock, 1991). Stocks from British
Columbia, Washington, and the Columbia River often have very early
(entering rivers in July or August) or late (spawning into March) runs
in addition to ``normally'' timed runs.
West Coast Chum Salmon
Chum salmon has the widest natural geographic and spawning
distribution of any Pacific salmonid, primarily because its range
extends further along the shores of the Arctic Ocean than other
salmonids. Chum salmon have been documented to spawn from Korea and the
Japanese island of Honshu, east, around the Pacific rim, to Monterey
Bay, California. Presently, major spawning populations are found only
as far south as Tillamook Bay on the Northern Oregon coast. The
species' range in the Arctic Ocean extends from the Laptev Sea in
Russia to the Mackenzie River in Canada. Chum salmon may historically
have been the most abundant of all salmonids; prior to the 1940s, it is
estimated that chum salmon contributed almost 50 percent of the total
biomass of all salmonids in the Pacific Ocean (Neave, 1961).
Chum salmon spawn primarily in freshwater, and apparently exhibit
obligatory anadromy, as there are no recorded landlocked or naturalized
freshwater populations (Randall et al., 1987). Chum salmon generally
spend more of their life history in marine waters than other Pacific
salmonids. Chum salmon usually spawn in coastal areas, and juveniles
out-migrate to seawater almost immediately after emerging from the
gravel that covers their redds (Salo, 1991). This ocean-type migratory
behavior contrasts with the stream-type behavior of some other species
in the genus Oncorhynchus (e.g., coastal cutthroat trout, anadromous O.
mykiss, coho salmon, and most types of chinook and sockeye salmon),
which usually migrate to sea at a larger size, after months or years of
freshwater rearing. This means survival and growth in juvenile chum
salmon depends less on freshwater conditions than on favorable
estuarine conditions.
West Coast O. mykiss
Steelhead is the name commonly applied to the anadromous form of
the biological species O. mykiss. The present distribution of steelhead
extends from Kamchatka in Asia, east to Alaska, and down to the U.S.-
Mexico border (Busby et al., 1996; 67 FR 21586, May 1, 2002). O. mykiss
exhibit perhaps the most complex suite of life history traits of any
species of Pacific salmonid. They can be anadromous, or freshwater
residents (and under some circumstances, apparently yield offspring of
the opposite form). Those that are anadromous can spend up to 7 years
in fresh water prior to smoltification, and then spend up to 3 years in
salt water prior to first spawning. O. mykiss is also iteroparous
(meaning individuals may spawn more than once), whereas the Pacific
salmon species are principally semelparous (meaning individuals
generally spawn once and die).
Within the range of West Coast steelhead, spawning migrations occur
throughout the year, with seasonal peaks of activity. In a given river
basin there may be one or more peaks in migration activity; since these
``runs'' are usually named for the season in which the peak occurs,
some rivers may have runs known as winter, spring, summer, or fall
steelhead. For example, large rivers, such as the Columbia, Rogue, and
Klamath rivers, have migrating adult steelhead at all times of the
year. There are local variations in the names used to identify the
seasonal runs of steelhead; in Northern California, some biologists
have retained the use of the terms spring and fall steelhead to
describe what others would call summer steelhead.
Steelhead can be divided into two basic reproductive ecotypes,
based on the state of sexual maturity at the time of river entry and
duration of spawning migration (Burgner et al., 1992). The ``stream-
maturing'' type (summer steelhead in the Pacific Northwest and Northern
California) enters fresh water in a sexually immature condition between
May and October and requires several months to mature and spawn. The
``ocean-maturing'' type (winter steelhead in the Pacific Northwest and
Northern California) enters fresh water between November and April with
well-developed gonads and spawns shortly thereafter. In basins with
both summer and winter steelhead runs, it appears that the summer run
occurs where habitat is not fully utilized by the winter run or a
seasonal hydrologic barrier, such as a waterfall, separates them.
Summer steelhead usually spawn farther upstream than winter steelhead
(Withler, 1966; Roelofs, 1983; Behnke, 1992). Coastal streams are
dominated by winter steelhead, whereas inland steelhead of the Columbia
River Basin are almost exclusively summer steelhead. Winter steelhead
may have been excluded from inland areas of the Columbia River Basin by
Celilo Falls or by the considerable migration distance from the ocean.
The Sacramento-San Joaquin River Basin may have historically had
multiple runs of steelhead that probably included both ocean-maturing
and stream-maturing stocks (CDFG, 1995; McEwan and Jackson, 1996).
These steelhead are referred to as winter steelhead by the California
Department of Fish and Game (CDFG); however, some biologists call them
fall steelhead (Cramer et al., 1995).
Inland steelhead of the Columbia River Basin, especially the Snake
River Subbasin, are commonly referred to as either ``A-run'' or ``B-
run.'' These designations are based on a bimodal distribution of
migration period of adult steelhead at Bonneville Dam (235 km from the
mouth of the Columbia River) and differences in age (1 versus 2 years
in the ocean) and adult size observed among Snake River steelhead. It
is unclear, however, if the life history and body size differences
observed upstream are correlated back to the groups forming the bimodal
migration observed at Bonneville Dam. Furthermore, the relationship
between patterns observed at the dams and the distribution of adults in
spawning areas throughout the
[[Page 33110]]
Snake River Basin is not well understood. A-run steelhead are believed
to occur throughout the steelhead-bearing streams of the Snake River
Basin and the inland Columbia River. B-run steelhead are thought to be
produced only in the Clearwater, Middle Fork Salmon, and South Fork
Salmon Rivers (IDFG, 1994).
The ``half-pounder'' is an immature steelhead that returns to fresh
water after only 2 to 4 months in the ocean, generally overwinters in
fresh water, and then outmigrates again the following spring. Half-
pounders are generally less than 400 mm and are reported only from the
Rogue, Klamath, Mad, and Eel Rivers of Southern Oregon and Northern
California (Snyder, 1925; Kesner and Barnhart, 1972; Everest, 1973;
Barnhart, 1986); however, it has been suggested that as mature
steelhead, these fish may only spawn in the Rogue and Klamath River
Basins (Cramer et al., 1995). Various explanations for this unusual
life history have been proposed, but there is still no consensus as to
what, if any, advantage it affords to the steelhead of these rivers.
Assessing Extinction Risk for Pacific Salmonids
Section 4(b) of the ESA requires the Secretary of Commerce
(Secretary) to make listing determinations after conducting a review of
the status of the species, and after taking into account those efforts,
if any, being made to protect the species. Such efforts being made to
protect the species include ``conservation'' practices, defined by the
ESA to include propagation and transplantation methods and procedures
(section 3(3)). The ESA requires that listing determinations be made
solely on the basis of the best scientific and commercial data
available to the Secretary. The ESA further requires that listing
decisions must take into account all members of the defined species
(Alsea Valley Alliance v. Evans, 161 F. Supp. 2d 1154, D. Oreg. 2001).
NMFS' Pacific Salmonid Biological Review Team (BRT) (an expert
panel of scientists from several federal agencies including NMFS, FWS,
and the U.S. Geological Survey) reviewed the viability and extinction
risk of naturally spawning populations in the 27 ESUs that are the
subject of this proposed rule (NMFS, 2003b). The BRT evaluated the risk
of extinction based on the performance of the naturally spawning
populations in each of the ESUs under the assumption that present
conditions will continue into the future. The BRT did not explicitly
consider artificial propagation in its evaluations.
The BRT assessed ESU-level extinction risk (as indicated by the
viability of the naturally spawning populations) at two levels: first,
at the simpler population level; then, at the overall ESU level. The
BRT used criteria for ``Viable Salmonid Populations'' (VSP; McElhany et
al., 2000) to guide its risk assessments. The VSP criteria were
developed to provide a consistent and logical reference for making
viability determinations and are based on a review and synthesis of the
conservation biology and salmon literature. Individual populations were
evaluated according to the four VSP criteria: Abundance, growth rate/
productivity, spatial structure, and diversity. These four parameters
are universal indicators of species' viability, and individually and
collectively function as reasonable predictors of extinction risk.
After reviewing all relevant biological information for the populations
in a particular ESU, the BRT ascribed an ESU-level risk score for each
of the four VSP criteria.
The viability of salmon and steelhead ESUs is characterized by the
health, abundance, productivity, spatial structure, and genetic/
behavioral diversity of the individual populations within the ESU
(McElhany et al., 2001). An ESU with a greater abundance of productive
populations will be more tolerant to environmental variation,
catastrophic events, genetic processes, demographic stochasticity,
ecological interactions, and other processes than one with a single or
a few populations (Caughley and Gunn, 1996; Foley, 1997; Meffe and
Carroll, 1994; Lande, 1993; Middleton and Nisbet, 1997). Similarly, an
ESU that is distributed across a variety of well-connected habitats can
better respond to environmental perturbations including catastrophic
events, than ESUs in which connectivity between populations has been
restricted or lost (Schlosser and Angermeier, 1995; Hanski and Gilpin,
1997; Tilman and Lehman, 1997; Cooper and Mangel, 1999). Genetic and
behavioral diversity and the maintenance of local adaptations within an
ESU allow for the exploitation of a wide array of environments, protect
against short-term environmental changes, and provide the raw material
for surviving long-term environmental change (Groot and Margolis, 1991;
Wood, 1995).
ESUs with fewer populations have greater risk of becoming extinct
due to catastrophic events, and have a lower likelihood that the
necessary phenotypic and genotypic diversity will exist to maintain
future viability than ESUs with more populations. ESUs with limited
geographic range are similarly at increased extinction risk due to
catastrophic events. ESUs with populations that are geographically
distant from each other, or are separated by severely degraded habitat,
may lack the connectivity to function as metapopulations and are more
likely to become extinct than populations that can function as
metapopulations. ESUs with limited life-history diversity are more
likely to become extinct as the result of correlated environmental
catastrophes or environmental change that occurs too rapidly for an
evolutionary response. ESUs comprised of a small proportion of
populations meeting or exceeding these viability criteria may lack the
``source'' populations to sustain the non-viable ``sink'' populations
during environmental downturns. ESUs consisting of a single population
are especially vulnerable in this regard.
Assessing an ESU involves evaluating the current biological
viability of the populations that comprise the ESU. The fact that the
current biological status of an ESU does not reflect historical
abundance, productivity, spatial structure or diversity does not mean
that it is currently not viable, but historical status serves as an
informative benchmark against which to weigh viability. Whether, upon
assessment, the biological status of an ESU meets the ESA's standard
for listing as either threatened or endangered--i.e., the ESU is in
danger of extinction throughout all or a significant portion of its
range or is likely to become so in the foreseeable future--depends on
which viability criteria it fails to meet, what the past trend has
been, whether that trend is likely to continue, and how far below the
benchmark it is.
Factors considered in relating the population-level VSP criteria to
ESU-level risk include: the total number of viable populations; the
geographic distribution of these populations; the connectivity among
populations; and the genetic, behavioral, and ecological diversity
among populations. ESUs with fewer populations are more likely to
become extinct due to catastrophic events, and have a lower likelihood
that the necessary phenotypic and genotypic diversity will exist to
maintain future viability. ESUs with limited geographic range are
similarly at increased extinction risk due to catastrophic events. ESUs
with populations that are geographically distant from each other, or
are separated by severely degraded habitat, may lack the connectivity
to function as metapopulations (i.e., a group of interconnected
subpopulations) and are more likely to become extinct. ESUs with
limited
[[Page 33111]]
diversity are more likely to go extinct as the result of correlated
environmental catastrophes or environmental change that occurs too
rapidly for an evolutionary response. ESUs comprised of a small
proportion of populations meeting or exceeding VSP criteria may lack
the source populations to sustain the non-viable declining populations
during environmental down-turns. ESUs consisting of a single population
are especially vulnerable in this regard. These considerations are
described in the BRT's report (NMFS 2003b), and further detailed in
McElhany et al. (2000) (and references therein). In short, a viable ESU
has a negligible risk (over a time scale of 100 years) of going extinct
as a result of normal environmental variation, genetic change,
catastrophic events and human activity. Viable ESUs and populations
have sufficient growth rates, possess variation in traits, and are
spatially distributed to survive environmental variation and natural
and human catastrophes.
After describing the ESU-level risk for each of the VSP criteria,
the BRT assessed ESU-level extinction risk based on the performance of
the naturally spawning populations. The BRT's assessment of ESU-level
extinction risk uses categories that correspond to the definitions of
endangered species and threatened species, respectively, in the ESA: in
danger of extinction throughout all or a significant portion of its
range, likely to become endangered within the foreseeable future
throughout all or a significant portion of its range, or neither. As
discussed above, these evaluations do not include consideration of
hatchery stocks included in ESUs, and do not evaluate efforts being
made to protect the species. Therefore, the BRT's findings are not to
be considered recommendations regarding listing. The BRT's ESU-level
extinction risk assessment reflects the BRT's professional scientific
judgment, guided by the analysis of the VSP criteria, as well as by
expectations about the likely interactions among the individual VSP
criteria. For example, a single VSP criterion with a ``High Risk''
score might be sufficient to result in an overall extinction risk
assessment of ``in danger of extinction,'' but a combination of several
VSP criteria with more moderate risk scores could also lead to the same
assessment, or a finding that the ESU is ``likely to become
endangered.''
Consideration of Artificial Propagation in Listing Determinations
In proposed listing determinations described in this proposed rule,
artificial propagation has been considered in (1) determining what
constitutes an ESU, and (2) when evaluating the extinction risk of an
entire ESU. NMFS' previous policy for these considerations for Pacific
salmon and steelhead (58 FR 17573; April 5, 1993) requires revision due
to the District Court's ruling in the Alsea case. In its February 2002
response to the Alsea decision and various petitions (67 FR 6215;
February 11, 2002), NMFS announced its plans to revise this policy.
NMFS had intended that rulemaking for the revised policy be completed
prior to the formulation of the proposed listing determinations
described in this notice. However, development of the revised policy
has been delayed as NMFS resolved complex scientific and policy issues.
Statutory and litigation deadlines compel NMFS to issue this proposed
rule together with proposed policy guidance on the consideration of
artificial propagation in its ESA listing determinations. A revised
policy for the consideration of artificial propagation in ESA listing
determinations (hereafter referred to as the proposed Hatchery Listing
Policy) is proposed elsewhere in this issue of the Federal Register.
The consideration of artificial propagation in the subject proposed
listing determinations is based on the proposed Hatchery Listing
Policy. Below, we summarize how artificial propagation was evaluated in
determining ESU membership and evaluating extinction risk of an entire
ESU. For further discussion of artificial propagation in the context of
ESA listing decisions, the reader is directed to the proposed Hatchery
Listing Policy.
Determining What Constitutes an ESU
In the Alsea ruling the Court affirmed NMFS' interpretation of what
constitutes a ``distinct population segment'' (i.e., the ESU Policy; 56
FR 58612; November 20, 1991), as a ``permissible agency construction of
the ESA'' (Alsea Valley Alliance v. Evans, 1612 F. Supp. 2d 1154, 1161
(D. Oreg. 2001)). NMFS believes that the ESU policy provides
appropriate guidance for the consideration of what populations (natural
as well as hatchery or resident populations) constitute an ESU, and
hence a ``species'' under the ESA. Under the ESU policy, a DPS of a
Pacific salmonid species is considered an ESU if it meets two criteria:
(a) It must be substantially reproductively isolated from other
conspecific population units; and (b) it must represent an important
component in the evolutionary legacy of the species. A key feature of
the ESU concept is the recognition of genetic resources that represent
the ecological and genetic diversity of the species. These genetic
resources can reside in a fish spawned in a hatchery (hatchery fish) as
well as in a fish spawned in the wild (natural fish).
In delineating an ESU that is to be considered for listing, NMFS
has identified all populations that are part of the ESU including
populations of natural fish (natural populations), populations of
hatchery fish (hatchery populations), and populations that include both
natural fish and hatchery fish (mixed populations). Hatchery fish with
a level of genetic divergence between the hatchery stocks and the local
natural populations that is no more than what would be expected between
closely related populations within the ESU (hereafter described as
``genetically no more than moderately divergent from the natural
population'') are considered part of the ESU and are considered in
determining whether an entire ESU warrants listing under the ESA.
Therefore, these hatchery fish must be included in any listing of the
ESU (See proposed Hatchery Listing Policy published elsewhere in this
issue of the Federal Register).
To assist NMFS in determining the ESU membership of individual
hatchery stocks, a Salmon and Steelhead Hatchery Assessment Group
(SSHAG), composed of NMFS scientists from the Northwest and Southwest
Fisheries Science Centers, evaluated the best available information
describing the relationships between hatchery stocks and natural ESA-
listed salmon and anadromous O. mykiss populations in the Pacific
Northwest and California. The SSHAG produced a report, entitled
``Hatchery Broodstock Summaries and Assessments for Chum, Coho, and
Chinook Salmon and Steelhead Stocks within Evolutionarily Significant
Units Listed under the Endangered Species Act'' (NMFS, 2003a),
describing the relatedness of each hatchery stock on the basis of stock
origin and the degree of known or inferred genetic divergence between
the hatchery stock and the local natural population(s). NMFS used the
information presented in the SSHAG Report to determine the ESU
membership of those hatchery stocks determined to be within the
historical geographic range of a given ESU. NMFS' assessment of
individual hatchery stocks and its findings regarding the ESU
membership are detailed in the Salmonid Hatchery Inventory and Effects
Evaluation Report (NMFS, 2004b). The hatchery stocks included in a
given ESU are listed below in the
[[Page 33112]]
``Determination of Species Under the ESA'' section.
Evaluating ESU Extinction Risk
Once ESU membership is determined, NMFS must assess the extinction
risk faced by an entire ESU. As described above, the BRT evaluated the
extinction risk for the naturally spawned component of an ESU. The
proposed Hatchery Listing Policy published elsewhere in this issue of
the Federal Register provides that status determinations for Pacific
salmonid ESUs will be based on the status of an entire ESU (including
both hatchery and natural components). For those ESUs with associated
hatchery programs, the BRT's findings represent a partial assessment of
the ESU's extinction risk. To assess the viability of an entire ESU,
NMFS has also assessed the contributions of within-ESU hatchery
programs to the viability of an ESU in-total.
There are, however, several reasons why long-term deleterious
consequences of such supplementation may outweigh the short-term
advantage of increased population size (NRC, 1995). In recent years,
various studies and scientific works have identified some potential
adverse effects of artificial propagation, including behavioral
differences that result in diminished fitness and survival of hatchery
fish relative to naturally spawned fish; genetic effects resulting from
poor broodstock and rearing practices (e.g., inbreeding, outbreeding,
domestication selection); incidence of disease; and increased rates of
competition with and predation on naturally spawned populations. In
assessing the risks to any particular population, however, it is often
difficult to demonstrate conclusively that adverse effects are actually
occurring, and, if they are demonstrated, how serious they are (CDFG/
NMFS, 2001).
In response to these concerns, there have been recent changes in
hatchery practices seeking to mitigate risks and enhance benefits of
artificial propagation. Continued scientific work is necessary to
identify and to measure these risks and benefits more completely, and
to assess the operations of hatcheries that implement modern management
practices. In light of the developing science on the positive and
negative effects of hatchery programs on natural populations, the
legacy of hatchery programs and the existing requirements to maintain
many of them present a challenge for developing a framework for
consideration of hatchery fish in listing determinations.
Because NMFS must base its listing determinations for Pacific
salmon and steelhead on the risk of extinction of the entire ESU,
including both natural and hatchery fish, the agency must consider the
likelihood that the hatchery and naturally spawned components will
contribute to the continued existence of the ESU into the future.
NMFS' assessment of the effects of ESU hatchery programs on ESU
viability and extinction risk is presented in the Salmonid Hatchery
Inventory and Effects Evaluation Report (NMFS, 2004b). The Report
evaluates the effects of hatchery programs on the likelihood of
extinction of an ESU on the basis of the four VSP criteria (i.e.,
abundance, productivity, spatial structure, and diversity) and how
artificial propagation efforts within the ESU affect those criteria. In
April 2004, NMFS convened an Artificial Propagation Evaluation Workshop
of federal scientists and managers with expertise in salmonid
artificial propagation. The Artificial Propagation Evaluation Workshop
reviewed the BRT's findings (NMFS, 2003a), evaluated the Salmonid
Hatchery Inventory and Effects Evaluation Report (NMFS, 2004b), and
assessed the overall extinction risk of ESUs with associated hatchery
stocks. Representatives of the BRT and NMFS' Northwest and Southwest
Fisheries Science Centers attended the workshop in an advisory capacity
to ensure that the BRT's findings were appropriately and accurately
considered, as well as to help ensure that the workshop participants
were aware of the best available scientific information. The
discussions and conclusions of the Artificial Propagation Evaluation
Workshop are detailed in a workshop report (NMFS, 2004c).
Finding on Trout Unlimited et al. Petitions
Two petitions from Trout Unlimited and co-petitioners, received by
the agency on April 29, 2002, sought to redefine 15 ESUs as including
only natural fish (i.e., naturally spawned fish and their progeny,
exclusive of all hatchery fish), and to list these redefined ESUs as
threatened or endangered species under the ESA, as appropriate. In a
Federal Register notice published on July 25, 2002 (67 FR 48601), NMFS
found that these petitions presented substantial scientific and
commercial information to suggest that the petitioned actions may be
warranted. Although proposed listing determinations for the subject
ESUs are included in this proposed rule, NMFS first addresses the
petitioners' arguments that the ESUs should be redefined to include
only natural fish.
The Trout Unlimited et al. petitions argue that hatchery stocks
should not be included in ESUs containing natural fish. The petitioners
contend that hatchery stocks are functionally distinct and
reproductively isolated from naturally spawned populations. The
petitioners present a substantial body of scientific information
describing the potential threats posed by hatchery stocks to natural
populations. Additionally, the petitioners present scientific
information documenting differences between hatchery and natural
populations in behavior, genetic composition, and reproductive fitness.
NMFS finds that the petitioners' argument that hatchery stocks are
functionally distinct and reproductively isolated from naturally
spawned populations is unsubstantiated. The derivation of hatchery
stocks from local natural populations and the established practice of
incorporating natural fish as hatchery broodstock results in hatchery
and natural populations that share the same evolutionary genetic and
ecological legacy. The SSHAG Report (NMFS, 2003a) and the Salmonid
Hatchery Inventory and Effects Evaluation Report (NMFS, 2004b) describe
the relationship of hatchery stocks to local natural populations, on
the basis of stock origin and the degree of known or inferred genetic
divergence between the hatchery stock and the local natural
population(s). The shared evolutionary legacy of certain hatchery
stocks with natural populations does not support the exclusion of these
hatchery stocks from ESUs containing natural fish. Such an approach
would also be inconsistent with NMFS' interpretation of the ESA that is
contained in its ESU policy, a policy that was affirmed by the Alsea
Court decision.
NMFS recognizes that artificial propagation under certain
circumstances can pose threats to natural populations. However, it is
not appropriate to include a consideration of the threats faced by an
ESU (such as any risks posed by artificial propagation) when
determining what constitutes a species under the ESA. Rather, such an
evaluation of threats is conducted after the ``species'' has been
defined, and the likelihood of extinction for the defined species is
being assessed. NMFS also recognizes that hatchery stocks may exhibit
differences in behavior, genetic composition, morphological traits, and
reproductive fitness from natural populations. Indeed, the presence of
such differences provides a valuable indicator of
[[Page 33113]]
divergence for determining whether a particular hatchery stock is
representative of the evolutionary legacy of an ESU.
NMFS concludes that the best available scientific and commercial
information does not support a finding that all hatchery stocks in the
15 petitioned ESUs should be redefined as distinct ESUs separate from
the naturally spawned populations from which they are derived.
Accordingly, NMFS finds that the action sought by the Trout Unlimited
et al. petitions is not warranted.
Consideration of Resident O. mykiss Populations in Listing
Determinations
In addition to an anadromous O. mykiss life history (i.e.,
steelhead), O. mykiss exhibits nonanadromous or resident forms (i.e.,
rainbow trout). Where the two forms co-occur, the offspring of resident
fish may migrate to the sea, and the offspring of anadromous fish may
remain in streams as resident fish. The change from the anadromous life
form to the resident life form can also result from imposed physical or
physiological barriers to migration. Genetic differences, when studied,
have indicated greater differences among geographically separated O.
mykiss populations of the same life-history form, than between
anadromous and resident life-history forms in the same geographical
area. No suite of morphological or genetic characteristics has been
found that consistently distinguishes between the two life-history
forms. As is the case with hatchery fish, it is important to determine
the relationship of these resident fish to anadromous populations in
the O. mykiss ESUs under consideration.
In its previous status reviews of steelhead ESUs (see Table 1),
NMFS concluded that the available data suggest that resident rainbow
trout and steelhead in the same area generally share a common gene pool
(at least over evolutionary time periods), and included resident and
anadromous populations in the same ESU. Resident populations above
long-standing natural barriers, and those populations that have
resulted from the introduction of non-native rainbow trout, were not
considered part of these ESUs. In the case of resident populations
upstream of impassable human-caused migration barriers (e.g., large
mainstem hydroelectric dams), NMFS found insufficient information to
merit their inclusion in steelhead ESUs. The agency generally concluded
that resident populations upstream of impassable manmade barriers must
be evaluated on a case-by-case basis as more information becomes
available on their relationships to below-barrier populations, or on
the role these above-barrier resident populations might play in
conserving below-barrier populations of O. mykiss.
In its previous steelhead ESA listing determinations, although NMFS
considered co-occurring resident and anadromous populations as a single
ESU, NMFS did not list resident populations when it was determined that
the ESU in-total warranted listing. As noted above, the Alsea court has
rejected listing under the ESA only a subset of an ESU or DPS. For the
purposes of reviewing the viability of naturally spawned O. mykiss
populations in this proposed rule, the BRT adopted a framework for
determining the ESU/DPS membership of resident O. mykiss geographically
associated with listed steelhead ESUs. These evaluations were guided by
the same biological principles used to define ESUs of natural fish and
determine ESU membership of hatchery fish: the extent of reproductive
isolation and biological divergence from other populations within the
ESU. Ideally, each resident population would be evaluated individually
on a case-by-case basis, using all available biological information. In
practice, little or no information is available for most resident O.
mykiss populations. To facilitate determinations of the ESU/DPS
membership of resident O. mykiss, the BRT identified three different
cases, reflecting the range of geographic relationships between
resident and anadromous forms within different watersheds: (1) No
obvious physical barriers to interbreeding between resident and
anadromous forms; (2) long-standing natural barriers (e.g., a
waterfall) between resident and anadromous forms; and (3) relatively
recent (e.g., within the last 100 years) human-imposed barriers (e.g.,
a dam without a fish ladder) between resident and anadromous forms.
The BRT adopted the following working assumptions about ESU
membership of resident fish falling in each of these three cases. Where
there was no obvious physical barrier to interbreeding between the two
life-history forms, resident fish were considered part of the ESU.
Empirical studies show that resident and anadromous O. mykiss are
typically very similar genetically when they co-occur with no physical
barriers to migration or interbreeding. Where long-standing natural
barriers separate resident and anadromous forms, resident populations
were not regarded as part of the ESU. Many populations in this category
have been isolated from contact with anadromous populations for
thousands of years. Empirical studies show that in these cases the
resident fish typically show substantial genetic and life-history
divergence from the nearest downstream anadromous populations. In cases
where the resident fish were separated from the anadromous form by
relatively recent human actions (e.g., impassable dams and culverts),
the BRT was unable to justify any particular default assumption. The
two life-history forms most likely coexisted without any barriers to
interbreeding prior to the establishment of the manmade barrier(s).
However, as a result of rapid divergence in a novel environment, or
displacement by or genetic introgression from non-native hatchery
rainbow trout, these resident populations may no longer represent the
evolutionary legacy of the O. mykiss ESU. Given these uncertainties,
the BRT left unresolved the ESU membership of O. mykiss above recent
(usually man-made) impassable barriers. In the absence of information
indicating that they are part of a common ESU, NMFS does not find such
above-barrier populations to be part of the O. mykiss ESUs under
review.
The BRT reviewed available information about individual resident
populations of O. mykiss to determine which of the above scenarios best
defined the level of reproductive isolation between the life-history
forms, and whether any information exists to override the default
assumptions described above about the ESU membership of resident
populations. The best available information concerning resident O.
mykiss in Columbia River Basin ESUs is summarized in the report ``The
Biological Implications of Non-Anadromous Oncorhynchus mykiss in
Columbia Basin Steelhead ESUs'' (Kostow, 2003).
As noted above, little or no population data are available for most
resident O. mykiss populations, greatly complicating assessments of
ESU-level extinction risk. Where available, the BRT incorporated
information about resident populations into their analyses of the four
VSP criteria and their assessments of extinction risk for O. mykiss
ESUs. As was often the case, no data on the abundance, productivity,
spatial structure, or diversity were available for resident populations
in an ESU. The BRT noted that the presence of relatively numerous
resident populations can significantly reduce risks to ESU abundance.
However, there is considerable scientific uncertainty as to how the
resident form affects
[[Page 33114]]
extinction risk through its influence on ESU productivity, spatial
structure, and diversity. The threats to O. mykiss ESUs extend beyond
low population size and include declining productivity, reduced
resilience of productivity to environmental variation, curtailed range
of distribution, impediments to population connectivity and
reproductive exchange, depleted diversity stemming from loss or
blockage of habitat and associated erosion of local adaptation, and
erosion of the diversity of expressed migratory behaviors. Thus, the
BRT concluded that, despite the reduced risk to abundance for certain
O. mykiss ESUs due to numerically abundant residents, the collective
contribution of the resident life-history form to the viability of an
ESU in-total is unknown and may not substantially reduce extinction
risks to an ESU in-total (NMFS, 2004). Based on present scientific
understanding, the BRT could not exclude the possibility that complete
loss of anadromous forms from within an ESU may be irreversible.
Consideration of Recent Ocean Conditions in Listing Determinations
In the last decade, evidence has shown: (1) Recurring, decadal-
scale patterns of ocean-atmosphere climate variability in the North
Pacific Ocean (Zang et al., 1997; Mantua et al., 1997); and (2)
correlations between these oceanic productivity ``regimes'' and salmon
population abundance in the Pacific Northwest and Alaska (Hare et al.,
1999; Mueter et al., 2002). There is little doubt that survival rates
in the marine environment are strong determinants of population
abundance for Pacific salmon and O. mykiss (NMFS, 2003b). It is also
generally accepted that for at least two decades, beginning about 1977,
marine productivity conditions were unfavorable for the majority of
salmon and O. mykiss populations in the Pacific Northwest (in contrast,
many populations in Alaska attained record abundances during this
period). Finally, there is evidence that an important shift in ocean-
atmosphere conditions occurred around July 1998. One indicator of the
ocean-atmosphere variation for the North Pacific is the Pacific Decadal
Oscillation index (PDO). Negative PDO values are associated with
relatively cool ocean temperatures (and generally high salmon
productivity) off the Pacific Northwest, and positive values are
associated with warmer, less productive conditions. These favorable
ocean conditions may also be correlated with favorable conditions in
the freshwater environment (e.g., above-average rainfalls resulting in
improved flow regimes for smolt outmigration). Increases in many salmon
populations in recent years may be largely a result of more favorable
ocean conditions. PDO values were mostly positive during the two
decades preceding 1998, and this regime was generally characterized by
less productive ocean conditions and declining salmonid abundances.
Between July 1998 and July 2002 the PDO exhibited mostly negative
values, associated with higher ocean productivity and increasing
returns for many salmonid populations. It is worth noting that from
August 2002 to April 2004 the PDO has exhibited positive values. It is
not clear what impact, if any, these most recent conditions will have
on salmonid populations. Although these facts are relatively well
established, much less certainty can be attached to any predictions
about what this means for the viability of salmon and O. mykiss ESUs
into the future.
The confidence with which we can project ocean-climate regimes into
the future is limited, and consequently so is our ability to project
the future influence of ocean-climate conditions on salmonid
productivity. There exists about a century of empirical evidence for
``cycles'' in the PDO, marine productivity, and salmon abundance. Such
a timeseries represents only about three PDO periods of 20 to 40 years
in duration. There are four main difficulties in inferring future
behavior of a complex system from data records spanning only a couple
cycles. First, the duration and magnitude of past cycles may not be
indicative of future dynamics. Second, the past decade has seen
particularly wide fluctuations not only in climatic indices (e.g., the
1997-1998 El Nino was in many ways the most extreme ever recorded, and
the 2001 drought was one of the most severe on record), but also in
abundance of salmon populations. In general, as the magnitude of
fluctuations in species' abundance increases, species extinction rates
increase. Third, if there is anthropogenically caused climate change,
it could affect future ocean productivity; however, how such change
might be manifested cannot be predicted with any certainty (IPCC 2001).
Finally, changes in the pattern of ocean-atmosphere interactions do not
affect all species (or even all populations of a given species) in the
same way (Peterman et al., 1998).
Given all these uncertainties, the BRT was reluctant to make any
specific assumptions about the future behavior of the ocean-atmospheric
systems or their effects on the distribution and abundance of salmon
and O. mykiss. The BRT was concerned, however, that even under the most
optimistic scenario, increases in abundance might be only temporary and
could mask a failure to address underlying factors for decline. The
real conservation concern for West Coast salmon and O. mykiss is not
how they perform during periods of high marine survival, but how
prolonged periods of poor marine survival affect the VSP parameters of
abundance, growth rate, spatial structure, and diversity. It is
reasonable to assume that salmon populations have persisted over time,
under pristine conditions through many such cycles in the past. Less
certain is how the populations will fare in periods of poor ocean
survival when their freshwater, estuary, and nearshore marine habitats
are degraded.
Treatment of the Listing Determination Steps for Each ESU Under Review
Determinations of ``Species'' Under the ESA
To qualify for listing as a threatened or endangered species, a
population (or group of populations) of West Coast salmonids must be
considered a ``species'' as defined under the ESA. The ESA defines a
species 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'' (ESA section 3(16)). NMFS
published a policy (56 FR 58612; November 20, 1991) describing the
agency's application of the ESA definition of ``species'' to anadromous
Pacific salmonid species. NMFS' policy provides that a Pacific salmonid
population (or group of populations) will be considered a DPS, and
hence a ``species'' under the ESA, if it represents an ESU of the
biological species. An ESU must be reproductively isolated from other
conspecific population units, and it must represent an important
component in the evolutionary legacy of the biological species. The
first criterion, reproductive isolation, need not be absolute, but must
be strong enough to permit evolutionarily important differences to
accrue in different population units. The second criterion is met if
the population unit contributes substantially to the ecological and
genetic diversity of the species in-total. Guidance on the application
of this policy is contained in 56 FR 58612 (November 20, 1991) and
Waples (1991). As noted in the ``Alsea Valley Alliance v. Evans''
section above, all components included in an ESU (natural populations,
hatchery stocks, resident populations, etc.) must be listed if it is
determined that the ESU in-
[[Page 33115]]
total is threatened or endangered under the ESA.
NMFS has reviewed the ESU relationships of hatchery salmon and
anadromous O. mykiss stocks (NMFS, 2004b), as well as of resident O.
mykiss populations. Hatchery stocks and resident populations are
included in an ESU if it is determined that they are not reproductively
isolated from populations in the ESU, and they are representative of
the evolutionary legacy of the ESU (see the ``Consideration of
Artificial Propagation in Listing Determinations'' section above).
Hatchery stocks are not considered representative of the evolutionary
legacy of an ESU, and hence not included in the ESU, if it is
determined that they are genetically no more than moderately divergent
from the natural population (See proposed Hatchery Listing Policy
published elsewhere in this issue of the Federal Register). If a
hatchery stock is more divergent from the local natural population,
this indicates that the hatchery stock is reproductively isolated from
the ESU. Co-occurring anadromous and resident O. mykiss populations
below impassable barriers are likely not reproductively isolated, so
that both represent important components of the evolutionary legacy of
the species, and hence are considered an ESU (see the more detailed
discussion above in the ``Consideration of Resident O. mykiss
Populations in Listing Determinations'' section).
The hatchery and resident components are detailed below for each
ESU, as applicable. More detailed descriptions of the hatchery stocks
included in the ESUs below can be found in the Salmonid Hatchery
Inventory and Effects Evaluation Report (NMFS, 2004b). More detailed
descriptions of the impassible barriers and resident populations
associated with O. mykiss ESUs are provided in the final BRT Report
(NMFS, 2003b) as well as in ``The Biological Implications of Non-
Anadromous Oncorhynchus mykiss in Columbia Basin Steelhead ESUs''
(Kostow, 2003).
A given hatchery stock determined to be part of an ESU may be
propagated at multiple sites. To more clearly convey the hatchery fish
that are included in a given ESU, the ESU descriptions below list the
artificial propagation programs that propagate hatchery stocks
determined to be part of the ESUs under review. A list of those
specific artificial propagation programs by ESU is provided for
reference in Table 2 at the end of this section.
The following descriptions of the 27 Pacific salmon and O. mykiss
ESUs addressed in this document generally reaffirm the ESU
determinations for naturally spawning populations detailed in previous
ESA status reviews and listing determinations (see Table 1). The BRT
focused primarily on risk assessments of the naturally spawned
component of ESUs. Apart from the consideration of hatchery stock and
resident O. mykiss populations, NMFS did not reconsider the geographic
boundaries of the ESUs under review. There was no significant
scientific and commercial information indicating that specific ESUs
boundaries warrant reconsideration.
Snake River Sockeye ESU
The Snake River sockeye ESU includes populations of anadromous
sockeye salmon from the Snake River Basin, Idaho (extant populations
occur only in the Stanley Basin) (56 FR 58619; November 20, 1991),
residual sockeye salmon in Redfish Lake, Idaho, as well as one captive
propagation hatchery program (Table 2). Artificially propagated sockeye
salmon from the Redfish Lake Captive Propagation program are considered
part of this ESU. NMFS has determined that this artificially propagated
stock is genetically no more than moderately divergent from the natural
population (NMFS, 2004b).
Subsequent to the 1991 listing determination for the Snake River
sockeye ESU, a ``residual'' form of Snake River sockeye (hereafter
``residuals'') was identified. The residuals often occur together with
anadromous sockeye salmon and exhibit similar behavior in the timing
and location of spawning. Residuals are thought to be the progeny of
anadromous sockeye salmon, but are generally nonanadromous. In 1993
NMFS determined that the residual population of Snake River sockeye
that exists in Redfish Lake is substantially reproductively isolated
from kokanee (i.e., nonanadromous populations of O. nerka that become
resident in lake environments over long periods of time), represents an
important component in the evolutionary legacy of the biological
species, and thus merits inclusion in the Snake River sockeye ESU.
Constituents and co-managers were subsequently advised that residual
sockeye salmon in Redfish Lake are part of the ESU and are listed as an
endangered species ``subject to all the protection, prohibitions, and
requirements of the ESA that apply to Snake River sockeye salmon''
(letter from Acting NMFS Director Nancy Foster to Constituents, dated
March 19, 1993).
Ozette Lake Sockeye ESU
The Ozette Lake sockeye ESU includes all naturally spawned
populations of sockeye salmon in Ozette Lake and streams and
tributaries flowing into Ozette Lake, Washington (64 FR 14528; March
25, 1999). Two artificial propagation programs are considered to be
part of this ESU (Table 2): the Umbrella Creek and Big River sockeye
hatchery programs. NMFS has determined that these artificially
propagated stocks are genetically no more than moderately divergent
from the natural population (NMFS, 2004b).
Sacramento Winter-run Chinook ESU
The Sacramento winter-run chinook ESU includes all naturally
spawned populations of winter-run chinook salmon in the Sacramento
River and its tributaries in California (59 FR 440; January 1, 1994),
as well as two artificial propagation programs (Table 2): winter-run
chinook from the Livingston Stone National Fish Hatchery (NFH), and
winter run chinook in a captive broodstock program maintained at
Livingston Stone NFH and the University of California Bodega Marine
Laboratory. NMFS has determined that these artificially propagated
stocks are no more than moderately diverged from the local natural
population (NMFS 2004b).
Central Valley Spring-run Chinook ESU
The Central Valley spring-run chinook ESU includes all naturally
spawned populations of spring-run chinook salmon in the Sacramento
River and its tributaries in California (64 FR 50394; September 16,
1999). This ESU does not include any artificially propagated spring-run
chinook stocks that reside within the historical geographic range of
the ESU.
California Coastal Chinook ESU
The California Coastal chinook ESU includes all naturally spawned
populations of chinook salmon from rivers and streams south of the
Klamath River to the Russian River, California (64 FR 50394; September
16, 1999). Seven artificial propagation programs are considered to be
part of the ESU (Table 2): the Humboldt Fish Action Council (Freshwater
Creek), Yager Creek, Redwood Creek, Hollow Tree, Van Arsdale Fish
Station, Mattole Salmon Group, and Mad River Hatchery fall-run chinook
hatchery programs. NMFS has determined that these artificially
propagated stocks are genetically no more than moderately divergent
from the natural populations (NMFS, 2004b).
[[Page 33116]]
Upper Willamette River Chinook ESU
The Upper Willamette River chinook ESU includes all naturally
spawned populations of spring-run chinook salmon in the Clackamas River
and in the Willamette River, and its tributaries, above Willamette
Falls, Oregon (64 FR 14208; March 24, 1999). Seven artificial
propagation programs are considered to be part of the ESU (Table 2):
the McKenzie River Hatchery (Oregon Department of Fish and Wildlife
(ODFW) stock 24), Marion Forks/North Fork Santiam River (ODFW
stock 21), South Santiam Hatchery (ODFW stock 23)
in the South Fork Santiam River, South Santiam Hatchery in the
Calapooia River, South Santiam Hatchery in the Mollala River,
Willamette Hatchery (ODFW stock 22), and Clackamas hatchery
(ODFW stock 19) spring-run chinook hatchery programs. NMFS
has determined that these artificially propagated stocks are
genetically no more than moderately divergent from the natural
populations (NMFS, 2004b).
Lower Columbia River Chinook ESU
The Lower Columbia River chinook ESU includes all naturally spawned
populations of chinook salmon from the Columbia River and its
tributaries from its mouth at the Pacific Ocean upstream to a
transitional point between Washington and Oregon east of the Hood River
and the White Salmon River, and includes the Willamette River to
Willamette Falls, Oregon, exclusive of spring-run chinook salmon in the
Clackamas River (64 FR 14208; March 24, 1999). Seventeen artificial
propagation programs are considered to be part of the ESU (Table 2):
the Sea Resources Tule chinook Program, Big Creek Tule chinook Program,
Astoria High School (STEP) Tule chinook Program, Warrenton High School
(STEP) Tule chinook Program, Elochoman River Tule chinook Program,
Cowlitz Tule Chinook Program, North Fork Toutle Tule chinook Program,
Kalama Tule chinook Program, Washougal River Tule chinook Program,
Spring Creek NFH Tule chinook Program, Cowlitz spring chinook Program
in the Upper Cowlitz River and the Cispus River, Friends of the Cowlitz
spring chinook Program, Kalama River spring chinook Program, Lewis
River spring chinook Program, Fish First spring chinook Program, and
the Sandy River Hatchery (ODFW stock 11) chinook hatchery
programs. NMFS has determined that these artificially propagated stocks
are genetically no more than moderately divergent from the natural
populations (NMFS, 2004b).
Upper Columbia River Spring-run Chinook ESU
The Upper Columbia River spring-run chinook ESU includes all
naturally spawned populations of chinook salmon in all river reaches
accessible to chinook salmon in Columbia River tributaries upstream of
the Rock Island Dam and downstream of Chief Joseph Dam in Washington,
excluding the Okanogan River (64 FR 14208; March 24, 1999). Six
artificial propagation programs are considered to be part of the ESU
(Table 2): the Twisp River, Chewuch River, Methow Composite, Winthrop
NFH, Chiwawa River, and White River spring-run chinook hatchery
programs. NMFS has determined that these artificially propagated stocks
are genetically no more than moderately divergent from the natural
populations (NMFS, 2004b).
Puget Sound Chinook ESU
The Puget Sound chinook ESU includes all naturally spawned
populations of chinook salmon from rivers and streams flowing into
Puget Sound including the Straits of Juan De Fuca from the Elwha River,
eastward, including rivers and streams flowing into Hood Canal, South
Sound, North Sound and the Strait of Georgia in Washington (64 FR
14208; March 24, 1999). Twenty-two artificial propagation programs are
considered to be part of the ESU (Table 2): the Kendal Creek Hatchery,
Marblemount Hatchery (fall, spring yearlings, spring subyearlings, and
summer run), Harvey Creek Hatchery, Whitehorse Springs Pond, Wallace
River Hatchery (yearlings and subyearlings), Tulalip Bay, Soos Creek
Hatchery, Icy Creek Hatchery, Keta Creek Hatchery, White River
Hatchery, White Acclimation Pond, Hupp Springs Hatchery, Voights Creek
Hatchery, Diru Creek, Clear Creek, Kalama Creek, Dungeness/Hurd Creek
Hatchery, Elwha Channel Hatchery chinook hatchery programs. NMFS has
determined that these artificially propagated stocks are genetically no
more than moderately divergent from the natural populations (NMFS,
2004b).
Snake River Fall-run Chinook ESU
The Snake River fall-run chinook ESU includes all naturally spawned
populations of fall-run chinook salmon in the mainstem Snake River and
in the Tucannon River, Grande Ronde River, Imnaha River, Salmon River,
and Clearwater River subbasins (57 FR 14653, April 22, 1992; 57 FR
23458, June 3, 1992). Four artificial propagation programs are
considered to be part of the ESU (Table 2): the Lyons Ferry Hatchery,
Fall Chinook Acclimation Ponds Program, Nez Perce Tribal Hatchery, and
Oxbow Hatchery fall-run chinook hatchery programs. NMFS has determined
that these artificially propagated stocks are genetically no more than
moderately divergent from the natural population (NMFS, 2004b).
Snake River Spring/Summer Chinook ESU
The Snake River spring/summer-run chinook ESU includes all
naturally spawned populations of spring/summer-run chinook salmon in
the mainstem Snake River and the Tucannon River, Grande Ronde River,
Imnaha River, and Salmon River subbasins (57 FR 23458; June 3, 1992).
Fifteen artificial propagation programs are considered to be part of
the ESU (Table 2): the Tucannon River conventional Hatchery, Tucannon
River Captive Broodstock Program, Lostine River, Catherine Creek,
Lookingglass Hatchery Reintroduction Program (Catherine Creek stock),
Upper Grande Ronde, Imnaha River, Big Sheep Creek, McCall Hatchery,
Johnson Creek Artificial Propagation Enhancement, Lemhi River Captive
Rearing Experiment, Pahsimeroi Hatchery, East Fork Captive Rearing
Experiment, West Fork Yankee Fork Captive Rearing Experiment, and the
Sawtooth Hatchery spring/summer-run chinook hatchery programs. NMFS has
determined that these artificially propagated stocks are genetically no
more than moderately divergent from the natural populations (NMFS,
2004b).
Central California Coast Coho ESU
The Central California Coast coho ESU includes all naturally
spawned populations of coho salmon from Punta Gorda in northern
California south to and including the San Lorenzo River in central
California, as well as populations in tributaries to San Francisco Bay,
excluding the Sacramento-San Joaquin River system (61 FR 56138; October
31, 1996). Four artificial propagation programs are considered part of
this ESU (Table 2): the Don Clausen Fish Hatchery Captive Broodstock
Program, Scott Creek/King Fisher Flats Conservation Program, Scott
Creek Captive Broodstock Program, and the Noyo River Fish Station Egg-
take Program coho hatchery programs. NMFS has determined that these
artificially propagated stocks are genetically no more than moderately
divergent from the natural populations (NMFS, 2004b).
Southern Oregon/Northern California Coast Coho ESU
The Southern Oregon/Northern California Coast coho ESU includes all
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naturally spawned populations of coho salmon in coastal streams between
Cape Blanco, Oregon, and Punta Gorda, California (62 FR 24588; May 6,
1997). Three artificial propagation programs are considered to be part
of the ESU (Table 2): the Cole Rivers Hatchery (ODFW stock
52), Trinity River Hatchery, and Iron Gate Hatchery coho hatchery
programs. NMFS has determined that these artificially propagated stocks
are no more than moderately diverged from the local natural populations
(NMFS, 2004b).
Oregon Coast Coho ESU
The Oregon Coast coho ESU includes all naturally spawned
populations of coho salmon in Oregon coastal streams south of the
Columbia River and north of Cape Blanco (63 FR 42587; August 10, 1998).
Five artificial propagation programs are considered part of the ESU
(Table 2): the North Umpqua River (ODFW stock 18), Cow Creek
(ODFW stock 37), Coos Basin (ODFW stock 37),
Coquille River (ODFW stock 44), and North Fork Nehalem River
(ODFW stock 32) coho hatchery programs. NMFS has determined
that these artificially propagated stocks are genetically no more than
moderately divergent from the natural populations (NMFS, 2004b).
Lower Columbia River Coho ESU
In NMFS' 1991 status review of Lower Columbia River (LCR) coho
(NMFS, 1991d), the BRT limited the geographic scope of its review to
the subject of the motivating listing petition: the LCR excluding the
Willamette River. The 1991 BRT concluded that historical LCR coho
populations were probably reproductively isolated from other coho
populations, but the BRT was unable to identify whether an historical
coho ESU still existed in the LCR. In the 1995 status review of West
Coast coho salmon (NMFS, 1995a), the BRT considered new information
suggesting that LCR coho may be part of a larger ESU, based on
similarities in physical and biogeographical conditions, and
preliminary genetic data. The 1995 BRT included LCR coho as part of a
larger Southwestern Washington (SWW)/LCR coho ESU, and NMFS designated
the SWW/LCR coho ESU as a candidate species (60 FR 38011; July 25,
1995). In 1996, NMFS' West Coast Coho Salmon BRT updated the 1995
status review, and concluded that the SWW/LCR ESU may warrant splitting
into separate SWW and LCR ESUs (NMFS, 1996e).
In 2001 the BRT reconvened to update information on the viability
of LCR coho and concluded that LCR coho is a separate ESU from SWW coho
(NMFS, 2001). This conclusion was supported by new tagging data and
analyses indicating that SWW and LCR coho populations have differing
marine distributions and are genetically distinct (Shaklee et al.,
1999; NMFS, 2001). This finding is consistent with the stock structure
exhibited by LCR chinook and O. mykiss populations (Myers et al.,
2003). The 2001 BRT also concluded that the historical ESU still exists
in the LCR. The primary evidence to support this conclusion is the
consistent genetic and life history differences between LCR coho salmon
and populations from other areas. The BRT concluded that, because of
presumably very low survival rates, stock transfers from Oregon coastal
populations 40 to 80 years ago probably had relatively little permanent
effect on the genetic makeup of LCR coho salmon. Nevertheless, the BRT
recognized that the ESU as it presently exists is much altered from
historical conditions, and evidence of appreciable natural production
is limited to two Oregon populations (in the Sandy and Clackamas
rivers) that represent the clearest link (through more or less
continuous natural production) to historical populations within the
ESU. Based on available information, most of the adult coho salmon
returning to natural or hatchery areas outside these two streams appear
to have themselves been reared as juveniles in hatcheries, or to have
had parents that were reared in hatcheries. The 2001 BRT concluded
that, collectively, these hatchery-produced fish contain a significant
portion of the historical diversity of LCR coho salmon, albeit in
somewhat altered form. In determining the upstream boundary of the LCR
coho ESU, the 2001 BRT concluded that Upper Columbia River coho (now
extinct) were likely not part of the LCR coho ESU, and that the Cascade
Crest represents the most likely eastern terminus of the LCR coho ESU.
The 2003 Pacific Salmonid BRT did not revisit the 2001 ESU boundaries
for the LCR coho ESU.
Based on the foregoing, NMFS concludes that the LCR coho ESU
includes all naturally spawned populations of coho salmon in the
Columbia River and its tributaries from the mouth of the Columbia up to
and including the Big White Salmon and Hood Rivers. Twenty-one
artificial propagation programs are considered to be part of the ESU
(Table 2): the Grays River, Sea Resources Hatchery, Peterson Coho
Project, Big Creek Hatchery, Astoria High School (STEP) Coho Program,
Warrenton High School (STEP) Coho Program, Elochoman Type-S Coho
Program, Elochoman Type-N Coho Program, Cathlamet High School FFA Type-
N Coho Program, Cowlitz Type-N Coho Program in the Upper and Lower
Cowlitz Rivers, Cowlitz Game and Anglers Coho Program, Friends of the
Cowlitz Coho Program, North Fork Toutle River Hatchery, Lewis River
Type-N Coho Program, Lewis River Type-S Coho Program, Fish First Wild
Coho Program, Fish First Type-N Coho Program, Syverson Project Type-N
Coho Program, Sandy Hatchery, and the Bonneville/Cascade/Oxbow complex
coho hatchery programs. NMFS has determined that these artificially
propagated stocks are genetically no more than moderately divergent
from the natural populations (NMFS, 2004b).
Columbia River Chum ESU
The Columbia River chum ESU includes all naturally spawned
populations of chum salmon in the Columbia River and its tributaries in
Washington and Oregon (64 FR 14508; March 25, 1999). Three artificial
propagation programs are considered to be part of the ESU (Table 2):
the Chinook River (Sea Resources Hatchery), Grays River, and Washougal
River/Duncan Creek chum hatchery programs. NMFS has determined that
these artificially propagated stocks are genetically no more than
moderately divergent from the natural populations (NMFS, 2004b).
Hood Canal Summer-run Chum ESU
The Hood Canal summer-run chum includes all naturally spawned
populations of summer-run chum salmon in Hood Canal and its tributaries
as well as populations in Olympic Peninsula rivers between Hood Canal
and Dungeness Bay, Washington (64 FR 14508; March 25, 1999). Eight
artificial propagation programs are considered to be part of the ESU
(Table 2): the Quilcene NFH, Hamma Hamma Fish Hatchery, Lilliwaup Creek
Fish Hatchery, Union River/Tahuya, Big Beef Creek Fish Hatchery, Salmon
Creek Fish Hatchery, Chimacum Creek Fish Hatchery, and the
Jimmycomelately Creek Fish Hatchery summer-run chum hatchery programs.
NMFS has determined that these artificially propagated stocks are
genetically no more than moderately divergent from the natural
populations (NMFS, 2004b).
Southern California O. mykiss ESU
The Southern California O. mykiss ESU includes all naturally
spawned populations of steelhead in streams from the Santa Maria River,
San Luis Obispo County, California (inclusive) to the U.S.-Mexico
Border (62 FR 43937,
[[Page 33118]]
August 18, 1997; 67 FR 21586, May 1, 2002). Resident populations of O.
mykiss below impassible barriers (natural and manmade) that co-occur
with anadromous populations are included in the Southern California O.
mykiss ESU. According to the framework discussed above (see the
Consideration of Resident O. mykiss Populations in Listing
Determinations section), the ESU membership of native resident
populations above recent (usually man-made) impassable barriers, but
below natural barriers, was not resolved. These resident populations
are provisionally not considered to be part of the Southern California
O. mykiss ESU, until such time that significant scientific information
becomes available affording a case-by-case evaluation of their ESU
relationships.
This ESU does not include any artificially propagated O. mykiss
stocks that reside within the historical geographic range of the ESU.
South-Central California Coast O. mykiss ESU
The South-Central California Coast O. mykiss ESU includes all
naturally spawned populations of steelhead in streams from the Pajaro
River (inclusive) to, but not including the Santa Maria River,
California (62 FR 43937; August 18, 1997). Resident populations of O.
mykiss below impassible barriers (natural and manmade) that co-occur
with anadromous populations are included in the South-Central
California Coast O. mykiss ESU. According to the framework discussed
above (See the Consideration of Resident O. mykiss Populations in
Listing Determinations section), the ESU membership of native resident
populations above recent (usually man-made) impassable barriers, but
below natural barriers, was not resolved. These resident populations
are provisionally not considered to be part of the South-Central
California Coast O. mykiss ESU, until such time that significant
scientific information becomes available affording a case-by-case
evaluation of their ESU relationships.
This ESU does not include any artificially propagated O. mykiss
stocks that reside within the historical geographic range of the ESU.
Central California Coast O. mykiss ESU
The Central California Coast O. mykiss ESU includes all naturally
spawned populations of steelhead in California streams from the Russian
River to Aptos Creek, and the drainages of San Francisco and San Pablo
Bays eastward to the Napa River (inclusive), excluding the Sacramento-
San Joaquin River Basin (62 FR 43937; August 18, 1997). Resident
populations of O. mykiss below impassible barriers (natural and
manmade) that co-occur with anadromous populations are included in the
Central California Coast O. mykiss ESU. According to the framework
discussed above (see the Consideration of Resident O. mykiss
Populations in Listing Determinations section), the ESU membership of
native resident populations above recent (usually man-made) impassable
barriers, but below natural barriers, was not resolved. These resident
populations are provisionally not considered to be part of the Central
California Coast O. mykiss ESU, until such time that significant
scientific information becomes available affording a case-by-case
evaluation of their ESU relationships. Recent genetic data regarding
three subpopulations of native fish above Rubber Dam 1 on Alameda Creek
strongly suggest that they are part of the ESU. Nielson (2003) found
that these subpopulations were most similar to each other and other
populations within the ESU than they were to populations outside the
ESU. NMFS, therefore, considers native resident O. mykiss populations
above Dam 1 on Alameda Creek to be part of the Central California Coast
O. mykiss ESU.
Two artificial propagation programs are considered to be part of
the ESU (Table 2): the Don Clausen Fish Hatchery, and Kingfisher Flat
Hatchery/Scott Creek (Monterey Bay Salmon and Trout Project) steelhead
hatchery programs. NMFS has determined that these artificially
propagated stocks are genetically no more than moderately divergent
from the natural populations (NMFS, 2004b).
California Central Valley O. mykiss ESU
The California Central Valley O. mykiss ESU includes all naturally
spawned populations of steelhead in the Sacramento and San Joaquin
Rivers and their tributaries, excluding steelhead from San Francisco
and San Pablo Bays and their tributaries (63 FR13347; March 19, 1998).
Resident populations of O. mykiss below impassible barriers (natural
and manmade) that co-occur with anadromous populations are included in
the California Central Valley O. mykiss ESU. According to the framework
discussed above (see the Consideration of Resident O. mykiss
Populations in Listing Determinations section), the ESU membership of
native resident populations above recent (usually man-made) impassable
barriers, but below natural barriers, was not resolved. These resident
populations are provisionally not considered to be part of the
California Central Valley O. mykiss ESU, until such time that
significant scientific information becomes available affording a case-
by-case evaluation of their ESU relationships.
Two artificial propagation programs are considered to be part of
the ESU (Table 2): the Coleman NFH, and Feather River Hatchery
steelhead hatchery programs. NMFS has determined that these
artificially propagated stocks are genetically no more than moderately
divergent from the natural populations (NMFS, 2004b).
Two other artificial propagation programs, the Nimbus and Mokelumne
River stocks, are derived from out-of-ESU broodstock, are genetically
more than moderately divergent from the ESU populations, and are not
considered part of this ESU.
Northern California O. mykiss ESU
The Northern California O. mykiss ESU includes steelhead in
California coastal river basins from Redwood Creek south to the Gualala
River (inclusive) (65 FR 36074; June 7, 2000). Resident populations of
O. mykiss below impassible barriers (natural and manmade) that co-occur
with anadromous populations are included in the Northern California O.
mykiss ESU. According to the framework discussed above (see the
Consideration of Resident O. mykiss Populations in Listing
Determinations section), the ESU membership of native resident
populations above recent (usually man-made) impassable barriers, but
below natural barriers, was not resolved. These resident populations
are provisionally not considered to be part of the Northern California
O. mykiss ESU, until such time that significant scientific information
becomes available affording a case-by-case evaluation of their ESU
relationships.
Two artificial propagation programs are considered part of the ESU
(Table 2): the Yager Creek Hatchery, and North Fork Gualala River
Hatchery (Gualala River Steelhead Project) steelhead hatchery programs.
NMFS has determined that these artificially propagated stocks are
genetically no more than moderately divergent from the natural
populations (NMFS, 2004b).
Upper Willamette River O. mykiss ESU
The Upper Willamette River O. mykiss ESU includes all naturally
spawned populations of winter-run steelhead in the Willamette River,
Oregon, and its tributaries upstream from Willamette Falls to the
Calapooia River (inclusive) (64 FR 14517; March 25, 1999). Resident
populations of O.
[[Page 33119]]
mykiss below impassible barriers (natural and manmade) that co-occur
with anadromous populations are included in the Upper Willamette River
O. mykiss ESU. Although there are no obvious physical barriers
separating populations upstream of the Calapooia from those lower in
the basin, resident O. mykiss in these upper basins are quite
distinctive both phenotypically and genetically and are not considered
part of the ESU. According to the framework discussed above (see the
Consideration of Resident O. mykiss Populations in Listing
Determinations section), the ESU membership of native resident
populations above recent (usually man-made) impassable barriers, but
below natural barriers, was not resolved. These resident populations
are provisionally not considered to be part of the Upper Willamette
River O. mykiss ESU, until such time that significant scientific
information becomes available affording a case-by-case evaluation of
their ESU relationships.
This ESU does not include any artificially propagated O. mykiss
stocks that reside within the historical geographic range of the ESU.
Hatchery summer steelhead occur in the Willamette Basin but are an out-
of-basin stock that is not included as part of the ESU.
Lower Columbia River O. mykiss ESU
The Lower Columbia River O. mykiss ESU includes all naturally
spawned populations of steelhead in streams and tributaries to the
Columbia River between the Cowlitz and Wind Rivers, Washington
(inclusive), and the Willamette and Hood Rivers, Oregon (inclusive).
Excluded are steelhead in the upper Willamette River Basin above
Willamette Falls and steelhead from the Little and Big White Salmon
Rivers in Washington (62 FR43937; August 18, 1997). Resident
populations of O. mykiss below impassible barriers (natural and
manmade) that co-occur with anadromous populations are included in the
Lower Columbia River O. mykiss ESU. According to the framework
discussed above (see the Consideration of Resident O. mykiss
Populations in Listing Determinations section), the ESU membership of
native resident populations above recent (usually man-made) impassable
barriers, but below natural barriers, was not resolved. These resident
populations are provisionally not considered to be part of the Lower
Columbia River O. mykiss ESU, until such time that significant
scientific information becomes available affording a case-by-case
evaluation of their ESU relationships.
Ten artificial propagation programs are considered to be part of
the ESU (Table 2): the Cowlitz Trout Hatchery (in the Cispus, Upper
Cowlitz, Lower Cowlitz, and Tilton Rivers), Kalama River Wild (winter-
and summer-run), Clackamas Hatchery, Sandy Hatchery, and Hood River
(winter- and summer-run) steelhead hatchery programs. NMFS has
determined that these artificially propagated stocks are genetically no
more than moderately divergent from the natural populations (NMFS,
2004b).
Middle Columbia River O. mykiss ESU
The Middle Columbia River O. mykiss ESU includes all naturally
spawned populations of steelhead in streams from above the Wind River,
Washington, and the Hood River, Oregon (exclusive), upstream to, and
including, the Yakima