[Federal Register Volume 61, Number 155 (Friday, August 9, 1996)]
[Proposed Rules]
[Pages 41541-41561]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-20030]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
50 CFR Parts 222 and 227
[Docket No. 960730210-6210-01; I.D. 050294D]
Endangered and Threatened Species: Proposed Endangered Status for
Five ESUs of Steelhead and Proposed Threatened Status for Five ESUs of
Steelhead in Washington, Oregon, Idaho, and California
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 a comprehensive status review of West Coast
steelhead (Oncorhynchus mykiss, or O. mykiss) populations in
Washington, Oregon, Idaho, and California, and has identified 15
Evolutionarily Significant Units (ESUs) within this range. NMFS is now
issuing a proposed rule to list five ESUs as endangered and five ESUs
as threatened under the Endangered Species Act (ESA). The endangered
steelhead ESUs are located in California (Central California Coast,
South/Central California Coast, Southern California, and Central Valley
ESUs) and Washington (Upper Columbia River ESU). The threatened
steelhead ESUs are dispersed throughout all four states and include the
Snake River Basin, Lower Columbia River, Oregon Coast, Klamath
Mountains Province, and Northern California ESUs. NMFS is also
designating the Middle Columbia River ESU as a candidate species.
NMFS is requesting public comments on the biological issues
pertaining to this proposed rule and suggestions on integrated local/
state/Federal conservation measures that might best achieve the
purposes of the ESA relative to recovering the health of steelhead
populations and the ecosystems upon which they depend. Should the
proposed listings be made final, protective regulations under the ESA
would be put into effect and a recovery program would be implemented.
DATES: Comments must be received by November 7, 1996. NMFS will
announce the dates and locations of public hearings in Washington,
Oregon, Idaho, and California in a separate Federal Register document.
Requests for additional public hearings must be received by September
23, 1996.
ADDRESSES: Comments on this proposed rule and requests for public
hearings or reference materials should be sent to the Protected Species
Branch, Environmental and Technical Services Division, NMFS, Northwest
Region, 525 NE Oregon Street, Suite 500, Portland, OR 97232-2737.
FOR FURTHER INFORMATION CONTACT: Garth Griffin, 503-231-2005, Craig
Wingert, 310-980-4021, or Marta Nammack, 301-713-1401.
SUPPLEMENTARY INFORMATION:
Background
On May 5, 1992, NMFS received a petition to list Illinois River
winter steelhead from the Oregon Natural Resources Council, the
Siskiyou Regional Education Project, Federation of Fly Fishers,
Kalmiopsis Audubon Society, Siskiyou Audubon Society, Klamath/Siskiyou
Coalition, Headwaters, The Wilderness Society, North Coast
Environmental Center, The Sierra Club--Oregon Chapter, and the National
Wildlife Federation. On July 31, 1992, NMFS published a notice stating
that the petition presented substantial information indicating that a
listing might be warranted (57 FR 33939) and concurrently solicited
information about the status of this population. NMFS completed a
status review (Busby et al. 1993) that was summarized in a May 20,
1993, determination (58 FR 29390). NMFS concluded that Illinois River
winter steelhead did not represent a ``species'' under the ESA and
therefore, a proposal to list this population was not warranted.
However, NMFS recognized that this population was part of a larger ESU
whose extent had not yet been determined, but whose status might
warrant listing because of declining trends in steelhead abundance
observed in several southern Oregon streams.
In its May 20, 1993, finding regarding Illinois River winter
steelhead, NMFS announced that it would conduct an expanded status
review to identify all coastal steelhead ESU(s) within California,
Oregon, and Washington, and to determine whether any identified ESU(s)
warrant listing under the ESA. Subsequently, on February 16, 1994, NMFS
received a petition from the Oregon Natural Resources Council and 15
co-petitioners to list all steelhead (or
[[Page 41542]]
specific ESUs, races, or stocks) within the states of California,
Oregon, Washington, and Idaho. In response to this petition, NMFS
announced the expansion of its status review of steelhead to include
inland steelhead populations occurring in eastern Washington and Oregon
and the State of Idaho (59 FR 27527, May 27, 1994).
On September 21, 1993, NMFS received a petition from Washington
Trout to list Deer Creek summer steelhead. On December 23, 1993, NMFS
concluded that the petition presented substantial information
indicating that listing may be warranted (58 FR 68108). NMFS completed
a status review which concluded that Deer Creek summer steelhead did
not represent a ``species'' under the ESA (59 FR 59981, November 21,
1994), and, therefore, a proposal to list this population under the ESA
was not warranted. However, NMFS further concluded that Deer Creek
summer steelhead were part of a larger ESU that may warrant listing
under the ESA and for which a status review was currently underway.
On March 16, 1995, NMFS published a proposed rule to list Klamath
Mountains Province steelhead as threatened (60 FR 14253). This proposal
included steelhead populations occurring in coastal streams between
Cape Blanco, OR, and the Klamath River Basin in Oregon and California,
inclusive. A brief summary of this ESU is included in the current
proposed rule. Public comments were received on this earlier proposal.
During the coastwide steelhead status review, NMFS assessed the
best available scientific and commercial data, including technical
information from Pacific Salmon Biological Technical Committees
(PSBTCs) and interested parties in Washington, Oregon, Idaho, and
California. The PSBTCs consisted primarily of scientists (from Federal,
state, and local resource agencies, Indian tribes, industries,
universities, professional societies, and public interest groups)
possessing technical expertise relevant to steelhead and their
habitats.
A NMFS Biological Review Team, composed of staff from NMFS'
Northwest Fisheries Science Center and Southwest Regional Office, as
well as a representative of the National Biological Service, has
completed a coastwide status review for steelhead [Memorandum to
William Stelle and Hilda Diaz-Soltero from M. Schiewe, July 17, 1995,
Review of the Status of Steelhead (O. mykiss) from Washington, Idaho,
Oregon, and California under the U.S. Endangered Species Act]. Copies
of the memorandum are available upon request (see ADDRESSES section).
The review, summarized below, identifies 15 ESUs of steelhead in the
four states. NMFS is proposing to list five ESUs as endangered and five
ESUs as threatened under the ESA. In addition, NMFS is proposing to add
the Middle Columbia River ESU to the candidate species list. The
complete results of NMFS' status review of steelhead populations will
be published in a forthcoming NOAA Technical Memorandum (Busby et al.,
in press).
Steelhead Life History
Steelhead exhibit one of the most complex suite of life history
traits of any salmonid species. Steelhead may exhibit anadromy (meaning
that they migrate as juveniles from fresh water to the ocean, and then
return to spawn in fresh water) or freshwater residency (meaning that
they reside their entire life in fresh water). Resident forms are
usually referred to as ``rainbow'' or ``redband'' trout, while
anadromous life forms are termed ``steelhead.'' Few detailed studies
have been conducted regarding the relationship between resident and
anadromous O. mykiss and as a result, the relationship between these
two life forms is poorly understood. Recently however, the scientific
name for the biological species that includes both steelhead and
rainbow trout was changed from Salmo gairdneri to O. mykiss. This
change reflects the premise that all trouts from western North America
share a common lineage with Pacific salmon.
Steelhead typically migrate to marine waters after spending 2 years
in fresh water. They then reside in marine waters for typically 2 or 3
years prior to returning to their natal stream to spawn as 4- or 5-
year-olds. Unlike Pacific salmon, steelhead are iteroparous, meaning
that they are capable of spawning more than once before they die.
However, it is rare for steelhead to spawn more than twice before
dying; most that do so are females. Steelhead adults typically spawn
between December and June (Bell, 1990). Depending on water temperature,
steelhead eggs may incubate in ``redds'' (nesting gravels) for 1.5 to 4
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 or ``fry'' and begin actively
feeding. Juveniles rear in fresh water from 1 to 4 years, then migrate
to the ocean as ``smolts.''
Biologically, steelhead can be divided into two reproductive
ecotypes, based on their state of sexual maturity at the time of river
entry and the duration of their spawning migration. These two ecotypes
are termed ``stream maturing'' and ``ocean maturing.'' Stream maturing
steelhead enter fresh water in a sexually immature condition and
require several months to mature and spawn. Ocean maturing steelhead
enter fresh water with well-developed gonads and spawn shortly after
river entry. These two reproductive ecotypes are more commonly referred
to by their season of freshwater entry (e.g., summer and winter
steelhead).
Two major genetic groups or ``subspecies'' of steelhead occur on
the west coast of the United States: a coastal group and an inland
group, separated in the Fraser and Columbia River Basins by the Cascade
crest approximately (Huzyk & Tsuyuki, 1974: Allendorf, 1975; Utter &
Allendorf, 1977; Okazaki, 1984; Parkinson, 1984; Schreck et al., 1986;
Reisenbichler et al., 1992). Behnke (1992) proposed to classify the
coastal subspecies as O. m. irideus and the inland subspecies as O. m.
gairdneri. These genetic groupings apply to both anadromous and
nonanadromous forms of O. mykiss. Both coastal and inland steelhead
occur in Washington and Oregon. California is thought to have only
coastal steelhead while Idaho has only inland steelhead.
Historically, steelhead were distributed throughout the North
Pacific Ocean from the Kamchatka Peninsula in Asia to the northern Baja
Peninsula. Presently, the species distribution extends from the
Kamchatka Peninsula, east and south along the Pacific coast of North
America, to at least Malibu Creek in southern California. There are
infrequent anecdotal reports of steelhead continuing to occur as far
south as the Santa Margarita River in San Diego County (McEwan &
Jackson, 1996). Historically, steelhead likely inhabited most coastal
streams in Washington, Oregon, and California as well as many inland
streams in these states and Idaho. However, during this century, over
23 indigenous, naturally-reproducing stocks of steelhead are believed
to have been extirpated, and many more are thought to be in decline in
numerous coastal and inland streams in Washington, Oregon, Idaho, and
California. Forty-three stocks have been identified by Nehlsen et al.
(1991) as being at moderate or high risk of extinction.
Consideration as a ``Species'' Under the ESA
To qualify for listing as a threatened or endangered species, the
identified populations of steelhead must be considered ``species''
under the ESA.
[[Page 41543]]
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.'' NMFS
published a policy (56 FR 58612, November 20, 1991) describing the
agencies application of the ESA definition of ``species'' to anadromous
Pacific salmonid species. NMFS's policy provides that a Pacific
salmonid population will be considered distinct and, hence, a species
under the ESA if it represents an ESU of the biological species. A
population must satisfy two criteria to be considered an ESU: (1) It
must be reproductively isolated from other conspecific population
units, and (2) 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
contributes substantially to the ecological/genetic diversity of the
species as a whole. Guidance on the application of this policy is
contained in a scientific paper ``Pacific Salmon (Oncorhynchus spp.)
and the Definition of `Species' under the Endangered Species Act'' and
a NOAA Technical Memorandum ``Definition of `Species' Under the
Endangered Species Act: Application to Pacific Salmon,'' which are
available upon request (see ADDRESSES). The following sections describe
the genetic, ecological, and life history characteristics, as well as
human-induced genetic changes that NMFS assessed to determine the
number and geographic extent of steelhead ESUs.
Reproductive Isolation
Genetic data provide useful indirect information on reproductive
isolation because they integrate information about migration and gene
flow over evolutionarily important time frames. During the status
review, NMFS worked in cooperation with the States of California,
Oregon, Idaho, and Washington to develop a genetic stock identification
data base for steelhead. Natural and hatchery steelhead were collected
by NMFS, California Department of Fish and Game (CDFG), Oregon
Department of Fish and Wildlife (ODFW), Idaho Department of Fish and
Game (IDFG), Washington Department of Fish and Wildlife (WDFW), and
U.S. Fish and Wildlife Service (USFWS) for protein electrophoretic
analysis by NMFS and WDFW. Existing NMFS data for Columbia and Snake
River Basin steelhead were also included in the data base.
In addition to the new studies, published results from numerous
studies of genetic characteristics of steelhead populations were
considered. These included studies based on protein electrophoresis
(Huzyk & Tsuyuki, 1974; Allendorf, 1975; Utter & Allendorf, 1977;
Okazaki, 1984; Parkinson, 1984; Campton & Johnson, 1985; Milner & Teel,
1985; Schreck et al., 1986; Hershberger & Dole, 1987; Berg & Gall,
1988; Reisenbichler & Phelps, 1989; Reisenbichler et al., 1992; Currens
& Schreck, 1993; Waples et al., 1993; Phelps et al., 1994; Leider et
al., 1995). Supplementing these protein electrophoretic studies were
two studies based on mitochondrial DNA (Buroker, unpublished; Nielsen,
1994) and chromosomal karyotyping studies conducted by Thorgard (1977,
1983) and Ostberg and Thorgard (1994).
Genetic information obtained from allozyme, DNA, and chromosomal
sampling indicate a strong differentiation between coastal and inland
subspecies of steelhead. Several studies have identified coastal and
inland forms of O. mykiss as distinct genetic life forms. Allendorf
(1975) first identified coastal and inland steelhead life forms in
Washington, Oregon, and Idaho based on large and consistent allele
frequency differences which applied to both anadromous and resident O.
mykiss. In the Columbia River, it was determined that the geographic
boundary of these life forms occurs at about the Cascade crest.
Subsequent studies have supported this finding (Utter & Allendorf,
1977; Okazaki, 1984; Schreck et al., 1986; Reisenbichler et al., 1992).
Recent genetic data from WDFW further supports the major
differentiation between coastal and inland steelhead forms.
Few detailed studies have explored the relationship between
resident and anadromous O. mykiss residing in the same location.
Genetic studies generally show that, in the same geographic area,
resident and anadromous life forms are more similar to each other than
either is to the same form from a different geographic area. Recently,
Leider et al. (1995) found that results from comparisons of rainbow
trout in the Elwha and Cedar Rivers and Washington steelhead indicate
that the two forms are not reproductively isolated. Further, Leider et
al. (1995) also concluded that, based on preliminary analyses of data
from the Yakima and Big White Salmon Rivers, resident trout would be
genetically indistinguishable from steelhead. Based on these studies,
it appears that resident and anadromous O. mykiss from the same
geographic area may share a common gene pool, at least over
evolutionary time periods.
Based on the available genetic information, it was the consensus of
NMFS scientists, as well as regional fishery biologists, that resident
fish should generally be considered part of the steelhead ESUs.
However, even though NMFS requested data regarding resident rainbow
trout abundance during its west coast steelhead status review, very
little was received, making status determinations with respect to
resident rainbow trout problematic. Because available information does
not clearly define the relationship between resident rainbow trout and
steelhead, NMFS is not proposing to list resident rainbow trout at this
time. However, through this proposed rule, NMFS is requesting public
comment regarding the inclusion of resident rainbow trout in proposed
steelhead ESUs. Prior to the final listing determination, NMFS will
work with the U.S. Fish and Wildlife Service (USFWS) and other
fisheries comanagers to examine the relationship between resident and
anadromous O. mykiss in the ESUs proposed for listing.
Genetic Changes Due to Human Activities
The effects of artificial propagation and other human activities
can be relevant to ESA listing determinations in two ways. First, such
activities can genetically change natural populations so much that they
no longer represent an evolutionarily significant component of the
biological species (Waples, 1991). For example, in 1991, NMFS concluded
that, as a result of massive and prolonged effects of artificial
propagation, harvest, and habitat degradation, the agency could not
identify natural populations of coho salmon (O. kisutch) in the lower
Columbia River that qualified for ESA listing consideration (56 FR
29553, June 27, 1991). Second, risks to the viability and genetic
integrity of native salmon populations posed by human activities may
contribute to their threatened or endangered status (Goodman, 1990;
Hard et al., 1992). The severity of these effects on natural
populations depends both on the nature of the effects (e.g., harvest
rate, gear size, or type of hatchery practice) and their magnitude
(e.g., duration of a hatchery program and number and life-history stage
of hatchery fish involved).
In the case of west coast steelhead, artificial propagation is a
common practice to supplement stocks for recreational fisheries.
However, in many
[[Page 41544]]
areas, a significant portion of the naturally spawning population
consists of hatchery-produced steelhead. In several of the steelhead
ESUs, over 50 percent of the naturally spawning fish are from
hatcheries. Many of these hatchery-produced fish are derived from a few
stocks which may or may not have originated from the geographic area
where they are released. Artificial propagation of steelhead has been,
and continues to be, a common occurrence throughout the range of west
coast steelhead. However, in several of the ESUs analyzed, insufficient
or uncertain information exists regarding the interactions between
hatchery and natural fish, and the relative abundance of hatchery and
natural stocks. The impacts of hatchery activities in specific ESUs is
discussed below under Status of Steelhead ESUs.
Ecological/Genetic Diversity
Several types of physical and biological evidence were considered
in evaluating the contribution of steelhead from Washington, Oregon,
Idaho, and California to the ecological/genetic diversity of the
biological species throughout its range. Factors examined included: (1)
The physical environment--geology, soil type, air temperature,
precipitation, river flow patterns, water temperature, and vegetation;
(2) biogeography--marine, estuarine, and freshwater fish distributions;
and (3) life history traits--age at smolting, age at spawning, river
entry timing, and spawning timing. An analysis of the physical
environment and life history traits provides important insight into the
ecological/genetic diversity of the species and can reflect unusual or
distinctive adaptations that promote evolutionary processes. Following
is a brief summary of the relevance of these factors for each ESU.
ESU Determinations
The ESU determinations described here represent a synthesis of a
large amount of diverse information. In general, the proposed
geographic boundaries for each ESU (i.e., the watersheds within which
the members of the ESU are typically found) are supported by several
lines of evidence that show similar patterns. However, the diverse data
sets are not always entirely congruent (nor would they be expected to
be), and the proposed boundaries are not necessarily the only ones
possible. For example, in some cases (e.g., in the Middle Columbia
River near the Cascade Crest), environmental changes occur over a
transition zone rather than abruptly.
Based on the best available scientific and commercial information,
including the biological effects of human activities, NMFS has
identified 15 ESUs that include steelhead populations from Washington,
Oregon, Idaho, and California. The 15 ESUs are briefly described and
characterized below. Genetic data (from studies of protein
electrophoresis and DNA) were the primary evidence considered for the
reproductive isolation criterion, supplemented by inferences about
barriers to migration created by natural geographic features and human-
induced changes resulting from artificial propagation and harvest.
Factors considered to be most informative in evaluating ecological/
genetic diversity include data pertaining to the physical environment,
ocean conditions/upwelling, vegetation, estuarine and freshwater fish
distributions, river entry, and spawning timing.
(1) Puget Sound
The geographic boundaries of this coastal steelhead ESU extend from
the United States/Canada border and include steelhead in river basins
of the Strait of Juan de Fuca, Puget Sound, and Hood Canal, WA.
Included are river basins east of and including the Elwha River and
north to include the Nooksack River. This region is in the rain shadow
of the Olympic Mountains, is therefore drier than the rainforest area
of the western Olympic Peninsula, and is dominated by western hemlock
forests. Streams are characterized by cold water, high average flows,
and a relatively long duration of peak flows that occur twice each
year.
Recent genetic data provided by WDFW show that steelhead in the
Puget Sound area generally form a coherent group distinct from
populations elsewhere in Washington. Chromosomal studies show that
steelhead from the Puget Sound area have a distinctive karyotype not
found in other regions. No recent genetic comparisons have been made
between Puget Sound and British Columbia steelhead; however, Nooksack
River steelhead tend to differ genetically from other Puget Sound
stocks, indicating a genetic transition zone in northern Puget Sound.
In life history traits, there appears to be a sharp transition
between steelhead populations from Washington, which smolt primarily at
age 2, and those in British Columbia, which most commonly smolt at age
3. This pattern holds for comparisons across the Strait of Juan de Fuca
as well as for comparisons of Puget Sound and Strait of Georgia
populations. At the present time, therefore, evidence suggests that the
northern boundary for this ESU coincides approximately with the United
States/Canada border. This ESU is primarily composed of winter
steelhead but includes several stocks of summer steelhead, usually in
subbasins of large river systems and above seasonal hydrologic
barriers.
(2) Olympic Peninsula
This coastal steelhead ESU occupies river basins of the Olympic
Peninsula, WA, west of the Elwha River and south to, but not including,
the rivers that flow into Grays Harbor, WA. Streams in the Olympic
Peninsula are similar to those in Puget Sound and are characterized by
high levels of precipitation and cold water, high average flows, and a
relatively long duration of peak flows that occur twice a year. In
contrast to the more inland areas of Puget Sound where western hemlock
is the dominant forest cover at sea level, lowland vegetation in this
region is dominated by Sitka spruce.
Genetic data collected by WDFW indicate that steelhead in this
region are substantially isolated from other regions in western
Washington. Only limited life history information is available for
Olympic Peninsula steelhead, and the information that does exist is
primarily from winter-run fish. As with the Puget Sound ESU, known life
history attributes of Olympic Peninsula steelhead are similar to those
for other west coast steelhead, the notable exception being the
difference between United States and Canadian populations in age at
smolting. This ESU is primarily composed of winter steelhead but
includes several stocks of summer steelhead in the larger rivers.
(3) Southwest Washington
This coastal steelhead ESU occupies the river basins of, and
tributaries to, Grays Harbor, Willapa Bay, and the Columbia River below
the Cowlitz River in Washington and below the Willamette River in
Oregon. Willapa Bay and Grays Harbor in southwest Washington have
extensive intertidal mud and sand flats and differ substantially from
estuaries to the north and south. This similarity between the Willapa
Bay and Grays Harbor estuaries results from the shared geology of the
area and the transportation of Columbia River sediments northward along
the Washington coast. Rivers draining into the Columbia River have
their headwaters in increasingly drier areas, moving from west to east.
Columbia River tributaries that drain the Cascade Mountains have
proportionally higher flows in late summer and early fall than rivers
on the Oregon coast.
[[Page 41545]]
Recent genetic data (Leider et al., 1995) show consistent
differences between steelhead populations from the southwest Washington
coast and coastal areas to the north, as well as Columbia River
drainages east of the Cowlitz River. Genetic data do not clearly define
the relationship between southwest Washington steelhead and lower
Columbia River steelhead. This ESU is primarily composed of winter
steelhead but includes summer steelhead in the Humptulips and Chehalis
River Basins.
(4) Lower Columbia River
This coastal steelhead ESU occupies tributaries to the Columbia
River between the Cowlitz and Wind Rivers in Washington and the
Willamette and Hood Rivers in Oregon. Excluded are steelhead in the
upper Willamette River Basin above Willamette Falls, and steelhead from
the Little and Big White Salmon Rivers in Washington. Similar to
Willapa Bay and Grays Harbor in southwest Washington, the lower
Columbia River has extensive intertidal mud and sand flats and differs
substantially from estuaries to the north and south. This similarity
results from the shared geology of the area and the transportation of
Columbia River sediments northward along the Washington coast. Rivers
draining into the Columbia River have their headwaters in increasingly
drier areas, moving from west to east. Columbia River tributaries that
drain the Cascade Mountains have proportionally higher flows in late
summer and early fall than rivers on the Oregon coast.
Steelhead populations in this ESU are of the coastal genetic group
(Schreck et al., 1986; Reisenbichler et al., 1992; Chapman et al.,
1994), and a number of genetic studies have shown that they are part of
a different ancestral lineage than inland steelhead from the Columbia
River Basin. Genetic data also show steelhead from this ESU to be
distinct from steelhead from the upper Willamette River and coastal
streams in Oregon and Washington. WDFW data showed genetic affinity
between the Kalama, Wind, and Washougal River steelhead. The data show
differentiation between the Lower Columbia River ESU and the Southwest
Washington and Middle Columbia River Basin ESUs. This ESU is composed
of winter steelhead and summer steelhead.
(5) Upper Willamette River
This coastal steelhead ESU occupies the Willamette River and its
tributaries, upstream from Willamette Falls. The Willamette River Basin
is zoogeographically complex. In addition to its connection to the
Columbia River, the Willamette has had connections with coastal basins
through stream capture and headwater transfer events (Minckley et al.,
1986).
Steelhead from the upper Willamette River are genetically distinct
from those in the lower river. Reproductive isolation from lower river
populations may have been facilitated by Willamette Falls, which is
known to be a migration barrier to some anadromous salmonids. For
example, winter steelhead and spring chinook salmon (O. tshawytscha)
occurred historically above the falls, but summer steelhead, fall
chinook salmon, and coho salmon did not (PGE, 1994).
The native steelhead of this basin are late-migrating winter
steelhead, entering fresh water primarily in March and April (Howell et
al., 1985), whereas most other populations of west coast winter
steelhead enter fresh water beginning in November or December. As early
as 1885, fish ladders were constructed at Willamette Falls to aid the
passage of anadromous fish. The ladders have been modified and rebuilt,
most recently in 1971, as technology has improved (Bennett, 1987; PGE,
1994). These fishways facilitated successful introduction of Skamania
stock summer steelhead and early-migrating Big Creek stock winter
steelhead to the upper basin. Another effort to expand the steelhead
production in the upper Willamette River was the stocking of native
steelhead in tributaries not historically used by that species. Native
steelhead primarily used tributaries on the east side of the basin,
with cutthroat trout predominating in streams draining the west side of
the basin.
Nonanadromous O. mykiss are known to occupy the Upper Willamette
River Basin; however, most of these nonanadromous populations occur
above natural and manmade barriers (Kostow, 1995). Historically,
spawning by Upper Willamette River steelhead was concentrated in the
North and Middle Santiam River Basins (Fulton, 1970). These areas are
now largely blocked to fish passage by dams, and steelhead spawning is
now distributed throughout more of the Upper Willamette River Basin
than in the past (Fulton, 1970). Due to introductions of nonnative
steelhead stocks and transplantation of native stocks within the basin,
it is difficult to formulate a clear picture of the present
distribution of native Upper Willamette River Basin steelhead, and
their relationship to nonanadromous and possibly residualized O. mykiss
within the basin.
(6) Oregon Coast
This coastal steelhead ESU occupies river basins on the Oregon
coast north of Cape Blanco, excluding rivers and streams that are
tributaries of the Columbia River. Most rivers in this area drain the
Coast Range Mountains, have a single peak in flow in December or
January, and have relatively low flow during summer and early fall. The
coastal region receives fairly high precipitation levels, and the
vegetation is dominated by Sitka spruce and western hemlock. Upwelling
off the Oregon coast is much more variable and generally weaker than
areas south of Cape Blanco. While marine conditions off the Oregon and
Washington coasts are similar, the Columbia River has greater influence
north of its mouth, and the continental shelf becomes broader off the
Washington coast.
Recent genetic data from steelhead in this ESU are limited, but
they show a level of differentiation from populations from Washington,
the Columbia River Basin, and coastal areas south of Cape Blanco. Ocean
migration patterns also suggest a distinction between steelhead
populations north and south of Cape Blanco. Steelhead (as well as
chinook and coho salmon) from streams south of Cape Blanco tend to be
south-migrating rather than north-migrating (Everest, 1973; Nicholas &
Hankin, 1988; Pearcy et al., 1990; Pearcy, 1992).
The Oregon Coast ESU primarily contains winter steelhead; there are
only two native stocks of summer steelhead. Summer steelhead occur only
in the Siletz River, above a waterfall, and in the North Umpqua River,
where migration distance may prevent full utilization of available
habitat by winter steelhead. Alsea River winter steelhead have been
widely used for steelhead broodstock in coastal rivers. Populations of
nonanadromous O. mykiss are relatively uncommon on the Oregon coast, as
compared with other areas, occurring primarily above migration barriers
and in the Umpqua River Basin (Kostow, 1995).
Little information is available regarding migration and spawn
timing of natural steelhead populations within this ESU. Age structure
appears to be similar to other west coast steelhead, dominated by 4-
year-old spawners. Iteroparity is more common among Oregon coast
steelhead than populations to the north.
(7) Klamath Mountains Province
This coastal steelhead ESU occupies river basins from the Elk River
in Oregon to the Klamath and Trinity Rivers in California, inclusive. A
detailed discussion of this ESU is presented in a previous NMFS status
review (Busby et al., 1994). Geologically, this region includes the
[[Page 41546]]
Klamath Mountains Province, which is not as erosive as the Franciscan
formation terrains south of the Klamath River Basin. Dominant
vegetation along the coast is redwood forest, while some interior
basins are much drier than surrounding areas and are characterized by
many endemic species. Elevated stream temperatures are a factor
affecting steelhead and other species in some of the larger river
basins. With the exception of major river basins such as the Rogue and
Klamath, most rivers in this region have a short duration of peak
flows. Strong and consistent coastal upwelling begins at about Cape
Blanco and continues south into central California, resulting in a
relatively productive nearshore marine environment.
Protein electrophoretic analyses of coastal steelhead have
indicated genetic discontinuities between the steelhead of this region
and those to the north and south (Hatch, 1990; Busby et al., 1993,
1994). Chromosomal studies have also identified a distinctive karyotype
that has been reported only from populations within this ESU. Steelhead
within this ESU include both winter and summer steelhead as well as the
unusual ``half-pounder'' life history (characterized by immature
steelhead that return to fresh water after only 2 to 4 months in salt
water, overwinter in rivers without spawning, then return to salt water
the following spring).
Among the remaining questions regarding this ESU is the
relationship between O. mykiss below and above Klamath Falls, OR.
Behnke (1992) has proposed that the two groups are in different
subspecies, and that the upper group, a redband trout (O. m.
newberrii), exhibited anadromy until blocked by the Copco dams in the
early 1900's. However, Moyle (1976) stated that Klamath Falls was the
upstream barrier to anadromous fish prior to construction of the dams.
(8) Northern California
This coastal steelhead ESU occupies river basins from Redwood Creek
in Humboldt County, CA to the Gualala River, inclusive. Dominant
vegetation along the coast is redwood forest, while some interior
basins are much drier than surrounding areas and are characterized by
many endemic species. This area includes the extreme southern end of
the contiguous portion of the Coast Range Ecoregion (Omernick, 1987).
Elevated stream temperatures are a factor in some of the larger river
basins (greater than 20 deg.C), but not to the extent that they are in
river basins farther south. Precipitation is generally higher in this
geographic area than in regions to the south, averaging 100-200 cm of
rainfall annually (Donley et al., 1979). With the exception of major
river basins such as the Eel, most rivers in this region have peak
flows of short duration. Strong and consistent coastal upwelling begins
at about Cape Blanco and continues south into central California,
resulting in a relatively productive nearshore marine environment.
There are life history similarities between steelhead of the
Northern California ESU and the Klamath Mountains Province ESU. This
ESU includes both winter and summer steelhead, including what is
presently considered to be the southernmost population of summer
steelhead, in the Middle Fork Eel River. Half-pounder juveniles also
occur in this geographic area, specifically in the Mad and Eel Rivers.
Snyder (1925) first described the half-pounder from the Eel River;
however, Cramer et al. (1995) suggested that adults with the half-
pounder juvenile life history may not spawn south of the Klamath River
Basin. As with the Rogue and Klamath Rivers, some of the larger rivers
in this area have migrating steelhead year-round, and seasonal runs
have been named. River entry ranges from August through June and
spawning from December through April, with peak spawning in January in
the larger basins and late February and March in the smaller coastal
basins.
(9) Central California Coast
This coastal steelhead ESU occupies river basins from the Russian
River to Soquel Creek, Santa Cruz County (inclusive), and the drainages
of San Francisco and San Pablo Bays; excluded is the Sacramento-San
Joaquin River Basin of the Central Valley of California. This area is
characterized by very erosive soils in the coast range mountains;
redwood forest is the dominant coastal vegetation for these drainages.
Precipitation is lower here than in areas to the north, and elevated
stream temperatures (greater than 20 deg.C) are common in the summer.
Coastal upwelling in this region is strong and consistent, resulting in
a relatively productive nearshore marine environment.
Analysis of mitochondrial DNA (mtDNA) data suggests that genetic
transitions occur north of the Russian River and north of Monterey,
California. Allozyme data show large genetic differences between
steelhead populations from the Eel and Mad Rivers and those to the
south. Only winter steelhead are found in this ESU and those to the
south. River entry ranges from October in the larger basins, late
November in the smaller coastal basins, and continues through June.
Steelhead spawning begins in November in the larger basins, December in
the smaller coastal basins, and can continue through April with peak
spawning generally in February and March. Little other life history
information exists for steelhead in this ESU.
(10) South/Central California Coast
This coastal steelhead ESU occupies rivers from the Pajaro River,
located in Santa Cruz County, CA, to (but not including) the Santa
Maria River. Most rivers in this ESU drain the Santa Lucia Range, the
southernmost unit of the California Coast Ranges. The climate is drier
and warmer than in the north, which is reflected in the vegetational
change from coniferous forest to chaparral and coastal scrub. Another
biological transition at the north of this area is the southern limit
of the distribution of coho salmon (O. kisutch). The mouths of many of
the rivers and streams in this area are seasonally closed by sand berms
that form during periods of low flow in the summer. The southern
boundary of this ESU is near Point Conception, a well-known transition
area for the distribution and abundance of marine flora and fauna.
Mitochondrial DNA data provide evidence for a genetic transition in
the vicinity of Monterey Bay. Both mtDNA and allozyme data show large
genetic differences between populations in this area, but do not
provide a clear picture of population structure. Only winter steelhead
are found in this ESU. River entry ranges from late November through
March, with spawning from January through April. Little other life
history information exists for steelhead in this ESU. The relationship
between anadromous and nonanadromous O. mykiss, including possibly
residualized fish upstream from dams, is unclear, but likely to be
important.
(11) Southern California
This coastal steelhead ESU occupies rivers from (and including) the
Santa Maria River to the southern extent of the species range which is
presently considered to be Malibu Creek, in Los Angeles County (McEwan
& Jackson, 1996). Migration and life history patterns of southern
California steelhead depend more strongly on rainfall and streamflow
than is the case for steelhead populations farther north (Moore, 1980;
Titus et al., in press). River entry ranges from early November through
June, with peaks in January and February. Spawning primarily begins in
January and continues through early June, with
[[Page 41547]]
peak spawning in February and March. Average rainfall is substantially
lower and more variable in this ESU than regions to the north,
resulting in increased duration of sand berms across the mouths of
streams and rivers and, in some cases, complete dewatering of the
marginal habitats. Environmental conditions in marginal habitats may be
extreme (e.g., elevated water temperatures, droughts, floods, and
fires) and presumably impose selective pressures on steelhead
populations. The use of southern California streams and rivers with
elevated temperatures by steelhead suggests that populations within
this ESU are able to withstand higher temperatures than those to the
north. The relatively warm and productive waters of the Ventura River
resulted in more rapid growth of juvenile steelhead than occurred in
northerly populations. However, relatively little life history
information exists for steelhead from this ESU.
Genetic data show large differences between steelhead populations
within this ESU as well as between these and populations to the north.
Steelhead populations between the Santa Ynez River and Malibu Creek
show a predominance of a mtDNA type that is rare in populations to the
north. Allozyme data indicate that two samples from Santa Barbara
County are genetically among the most distinctive of any natural
populations of coastal steelhead yet examined.
Among the remaining questions regarding this ESU are the
distribution and abundance of steelhead south of Malibu Creek. For
example, in years of substantial rainfall there have been reports of
steelhead in some coastal streams as far south as the Santa Margarita
River, San Diego County (Hubbs, 1946; Barnhart, 1986; Higgins, 1991;
McEwan & Jackson, 1996; Titus et al., in press).
(12) Central Valley
This coastal steelhead ESU occupies the Sacramento and San Joaquin
Rivers and their tributaries. In the San Joaquin Basin, however, the
best available information suggests that the current range of steelhead
has been limited to the Stanislaus, Tuolumne, and Merced Rivers
(tributaries), and the mainstem San Joaquin River to its confluence
with the Merced River by human alteration of formerly available
habitat. The Sacramento and San Joaquin Rivers offer the only migration
route to the drainages of the Sierra Nevada and southern Cascade
mountain ranges for anadromous fish. The distance from the Pacific
Ocean to spawning streams can exceed 300 km, providing unique potential
for reproductive isolation among steelhead. The Central Valley is much
drier than the coastal regions to the west, receiving on average only
10-50 cm of rainfall annually. The valley is characterized by alluvial
soils, and native vegetation was dominated by oak forests and prairie
grasses prior to agricultural development. Steelhead within this ESU
have the longest freshwater migration of any population of winter
steelhead. There is essentially one continuous run of steelhead in the
upper Sacramento River. River entry ranges from July through May, with
peaks in September and February. Spawning begins in late December and
can extend into April (McEwan & Jackson, 1996).
Steelhead ranged throughout the tributaries and headwaters of the
Sacramento and San Joaquin Rivers prior to dam construction, water
development, and watershed perturbations of the 19th and 20th
centuries. Present steelhead distribution in the central valley
drainages has been greatly reduced (McEwan & Jackson, 1996),
particularly in the San Joaquin basin. While there is little historical
documentation regarding steelhead distribution in the San Joaquin River
system, it can be assumed (based on known chinook salmon distributions
in this drainage) that steelhead were present in the San Joaquin River
and its tributaries from at least the San Joaquin River headwaters
northward. With regards to the present distribution of steelhead, there
is also only limited information. McEwan and Jackson (1996) reported
that a small, remnant run of steelhead persists in the Stanislaus
River, that steelhead were observed in the Tuolumne River in 1983, and
that a few large rainbow trout that appear to be steelhead enter the
Merced River Hatchery annually.
Recent allozyme data show that samples of steelhead from Deer and
Mill Creeks and Coleman NFH on the Sacramento River are well
differentiated from all other samples of steelhead from California.
There are two recognized taxonomic forms of native O. mykiss within the
Sacramento River Basin: Coastal steelhead/rainbow trout (O. m. irideus,
Behnke, 1992) and Sacramento redband trout (O. m. stonei, Behnke,
1992). It is not clear how the coastal and Sacramento redband forms of
O. mykiss interacted in the Sacramento River prior to construction of
Shasta Dam in the 1940s. However, it appears the two forms historically
co-occurred at spawning time, but may have maintained reproductive
isolation.
Among the remaining questions regarding this ESU are the current
presence, distribution, and abundance of steelhead in the San Joaquin
River and its main tributaries (stanislaus, tuolumne, and Merced
Rivers), and whether these steelhead stocks historically represented a
separate ESU from those in the Sacramento River Basin. Also, the
relationship between anadromous and nonanadromous O. mykiss, including
possibly residualized fish upstream from dams, is unclear.
(13) Middle Columbia River Basin
This inland steelhead ESU occupies the Columbia River Basin from
Mosier Creek, OR, upstream to the Yakima River, WA, inclusive.
Steelhead of the Snake River Basin are excluded. Franklin and Dyrness
(1973) placed the Yakima River Basin in the Columbia Basin
Physiographic Province, along with the Deschutes, John Day, Walla
Walla, and lower Snake River Basins. Geology within this province is
dominated by the Columbia River Basalt formation, stemming from lava
deposition in the miocene epoch, overlain by plio-Pleistocene deposits
of glaciolacustrine origin (Franklin & Dyrness, 1973). This
intermontane region includes some of the driest areas of the Pacific
Northwest, generally receiving less than 40 cm of rainfall annually
(Jackson, 1993). Vegetation is of the shrub-steppe province, reflecting
the dry climate and harsh temperature extremes.
Genetic differences between inland and coastal steelhead are well
established, although some uncertainty remains about the exact
geographic boundaries of the two forms in the Columbia River (see
discussion above for the Lower Columbia River ESU). Electrophoretic and
meristic data show consistent differences between steelhead from the
middle Columbia and Snake Rivers. No recent genetic data exist for
natural steelhead populations in the upper Columbia River, but recent
WDFW data show that the Wells Hatchery stock from the upper Columbia
River does not have a close genetic affinity to sampled populations
from the middle Columbia River.
All steelhead in the Columbia River Basin upstream from The Dalles
Dam are summer-run, inland steelhead (Schreck et al., 1986;
Reisenbichler et al., 1992; Chapman et al., 1994). Steelhead in
Fifteenmile Creek, OR, are genetically allied with inland O. mykiss,
but are winter-run. Winter steelhead are also found in the Klickitat
and White Salmon Rivers, WA.
Life history information for steelhead of this ESU indicates that
most middle Columbia River steelhead smolt at 2 years and spend 1 to 2
years in salt
[[Page 41548]]
water (i.e., 1-ocean and 2-ocean fish, respectively) prior to re-
entering fresh water, where they may remain up to a year prior to
spawning (Howell et al., 1985; BPA, 1992). Within this ESU, the
Klickitat River is unusual in that it produces both summer and winter
steelhead, and the summer steelhead are dominated by 2-ocean steelhead,
whereas most other rivers in this region produce about equal numbers of
both 1- and 2-ocean steelhead.
(14) Upper Columbia River Basin
This inland steelhead ESU occupies the Columbia River Basin
upstream from the Yakima River, WA, to the United States/Canada Border.
The geographic area occupied by this ESU forms part of the larger
Columbia Basin Ecoregion (Omernik, 1987). The Wenatchee and Entiat
Rivers are in the Northern Cascades Physiographic Province, and the
Okanogan and Methow Rivers are in the Okanogan Highlands Physiographic
Province. The geology of these provinces is somewhat similar and very
complex, developed from marine invasions, volcanic deposits, and
glaciation (Franklin & Dyrness, 1973). The river valleys in this region
are deeply dissected and maintain low gradients except in extreme
headwaters. The climate in this area includes extremes in temperatures
and precipitation, with most precipitation falling in the mountains as
snow. Streamflow in this area is provided by melting snowpack,
groundwater, and runoff from alpine glaciers. Mullan et al. (1992)
described this area as a harsh environment for fish and stated that
``it should not be confused with more studied, benign, coastal streams
of the Pacific Northwest.''
Life history characteristics for Upper Columbia River Basin
steelhead are similar to those of other inland steelhead ESUs; however,
some of the oldest smolt ages for steelhead, up to 7 years, are
reported from this ESU. This may be associated with the cold stream
temperatures (Mullan et al., 1992). Based on limited data available
from adult fish, smolt age in this ESU is dominated by 2-year-olds.
Steelhead from the Wenatchee and Entiat Rivers return to fresh water
after 1 year in salt water, whereas Methow River steelhead are
primarily 2-ocean resident (Howell et al., 1985).
In 1939, the construction of Grand Coulee Dam on the Columbia River
(RKm 956) blocked over 1,800 km of river from access by anadromous fish
(Mullan et al., 1992). In an effort to preserve fish runs affected by
Grand Coulee Dam, all anadromous fish migrating upstream were trapped
at Rock Island Dam (RKm 729) from 1939 through 1943 and either released
to spawn in tributaries between Rock Island and Grand Coulee Dams or
spawned in hatcheries and the offspring released in that area (Peven,
1990; Mullan et al., 1992; Chapman et al., 1994). Through this process,
stocks of all anadromous salmonids, including steelhead, which
historically were native to several separate subbasins above Rock
Island Dam, were randomly redistributed among tributaries in the Rock
Island-Grand Coulee reach. Exactly how this has affected stock
composition of steelhead is unknown.
(15) Snake River Basin
This inland steelhead ESU occupies the Snake River Basin of
southeast Washington, northeast Oregon and Idaho. The Snake River flows
through terrain that is warmer and drier on an annual basis than the
upper Columbia Basin or other drainages to the north. Geologically, the
land forms are older and much more eroded than most other steelhead
habitat. The eastern portion of the basin flows out of the granitic
geological unit known as the Idaho Batholith. The western Snake River
Basin drains sedimentary and volcanic soils of the Blue Mountains
complex. Collectively, the environmental factors of the Snake River
Basin result in a river that is warmer and more turbid, with higher pH
and alkalinity, than is found elsewhere in the range of inland
steelhead.
Snake River Basin steelhead are summer steelhead, as are most
inland steelhead, and comprise 2 groups, A-run and B-run, based on
migration timing, ocean-age, and adult size. Snake River Basin
steelhead enter fresh water from June to October and spawn in the
following spring from March to May. A-run steelhead are thought to be
predominately l-ocean, while B-run steelhead are thought to be 2-ocean
(IDFG, 1994). Snake River Basin steelhead usually smolt at age-2 or -3
years (Whitt, 1954; BPA, 1992; Hassemer, 1992).
The steelhead population from Dworshak National Fish Hatchery (NFH)
is the most divergent single population of inland steelhead based on
genetic traits determined by protein electrophoresis. Additionally,
steelhead returning to Dworshak NFH are considered to have a
distinctive appearance and are the one steelhead population that is
consistently referred to as B-run. NMFS considered the possibility that
Dworshak NFH steelhead should be in their own ESU. However, little
specific information was available regarding the characteristics of
this population's native habitat in the North Fork Clearwater River,
which is currently unavailable to anadromous fish due blockage by
Dworshak Dam.
Status of Steelhead ESUs
The ESA defines the term ``endangered species'' as ``any species
which is in danger of extinction throughout all or a significant
portion of its range.'' The term ``threatened species'' is defined as
``any species which is likely to become an endangered species within
the foreseeable future throughout all or a significant portion of its
range.'' Thompson (1991) suggested that conventional rules of thumb,
analytical approaches, and simulations may all be useful in making this
determination. In previous status reviews (e.g., Weitkamp et al.,
1995), NMFS has identified a number of factors that should be
considered in evaluating the level of risk faced by an ESU, including:
(1) Absolute numbers of fish and their spatial and temporal
distribution; (2) current abundance in relation to historical abundance
and current carrying capacity of the habitat; (3) trends in abundance;
(4) natural and human-influenced factors that cause variability in
survival and abundance; (5) possible threats to genetic integrity
(e.g., from strays or outplants from hatchery programs); and (6) recent
events (e.g., a drought or changes in harvest management) that have
predictable short-term consequences for abundance of the ESU.
During the coastwide status review for steelhead, NMFS evaluated
both quantitative and qualitative information to determine whether any
proposed ESU is threatened or endangered according to the ESA. The
types of information used in these assessments are described below,
followed by a summary of results for each ESU.
Quantitative Assessments: A significant component of NMFS' status
determination was analyses of abundance trend data. Principal data
sources for these analyses were historical and recent runsize estimates
derived from dam and weir counts, stream surveys, and angler catch
estimates. Of the 160 steelhead stocks for which sufficient data
existed, 118 (74 percent) exhibited declining trends in abundance,
while the remaining 42 (26 percent) exhibited increasing trends in
abundance. Sixty-five of the stock abundance trends analyzed were
statistically significant. Of these, 57 (88 percent) indicated
declining trends in abundance and the remaining 8 (12 percent)
indicated increasing trends in
[[Page 41549]]
abundance. It should be noted that NMFS' analysis assumes that catch
trends reflect trends in overall population abundance. NMFS recognizes
that there are many problems with this assumption, with the result that
the index may not precisely represent trends in the total population in
a river basin. However, angler catch is the only information available
for many steelhead populations, and changes in catch still provide a
useful indication of trends in total population abundance.
Analyses of steelhead abundance indicate that across the species'
range, the majority of naturally-reproducing steelhead stocks have
exhibited declining long-term trends in abundance. The severity of
declines in abundance tends to vary by geographic region. Based on
historical and recent abundance estimates, stocks in the southern
extent of the coastal steelhead range (i.e., California's Central
Valley, South/Central and Southern California ESUs) appear to have
declined significantly, with widespread stock extirpations. Northern
areas of the coastal steelhead range tend to be relatively more stable
with larger overall population sizes. However, stocks in these areas
continue to exhibit downward abundance trends as well. In several
areas, a lack of accurate runsize and trend data make estimating
abundance difficult.
Qualitative Assessments: Numerous studies have attempted to
classify the status of steelhead populations on the west coast of the
United States. However, problems exist in applying results of these
studies to NMFS' ESA evaluations. A significant problem is that the
definition of ``stock'' or ``population'' varies considerably in scale
among studies, and sometimes among regions within a study. In several
studies, identified units range in size from large river basins, to
minor coastal streams and tributaries. Only two studies (Nehlsen et
al., 1991; Higgins et al., 1992) used categories which relate to the
ESA ``threatened'' or ``endangered'' status. However, these studies
applied their own interpretations of these terms to individual stocks,
not to broader geographic units such as those discussed here. Another
significant problem in applying previously published studies to this
evaluation is the manner in which stocks or populations were selected
to be included in the review. Several studies did not evaluate stocks
which were not perceived to be at risk; therefore, it is difficult to
determine the proportion of stocks they considered to be at risk in any
given area.
Nehlsen et al. (1991) considered salmon and steelhead stocks
throughout Washington, Idaho, Oregon, and California and enumerated all
stocks that they found to be extinct or at risk of extinction. They
considered 23 steelhead stocks to be extinct, one possibly extinct, 27
at high risk of extinction, 18 at moderate risk of extinction, and 30
of special concern. Steelhead stocks that do not appear in their
summary were either not at risk of extinction or there was insufficient
information to classify them. Higgins et al. (1992) used the same
classification scheme as Nehlsen et al. (1991), but provided a more
detailed review of northern California salmon stocks. Of the eleven
steelhead stocks Higgins et al. identified as being at some risk of
extinction, eight were classified as at high risk, two were classified
as at moderate risk, and one was classified as of concern. Nickelson et
al. (1992) rated coastal Oregon (excluding Columbia River Basin) salmon
and steelhead stocks on the basis of their status over the past 20
years, classifying stocks as ``depressed'' (spawning habitat
underseeded, declining trends, or recent escapements below long-term
average), ``healthy'' (spawning habitat fully seeded and stable or
increasing trends), or ``of special concern'' (300 or fewer spawners or
a problem with hatchery interbreeding). Of 27 coastal populations
identified, 5 were classified as healthy, 1 as of special concern, and
21 as depressed. Washington Department of Fisheries et al. (1993)
categorized all salmon and steelhead stocks in Washington on the basis
of stock origin (``native,'' ``non-native,'' ``mixed,'' or
``unknown''), production type (``wild,'' ``composite,'' or ``unknown'')
and status (``healthy,'' ``depressed,'' ``critical,'' or ``unknown'').
Of the 141 steelhead stocks identified in Washington, 36 were
classified as healthy, 44 as critical, 1 as depressed, and 60 as
unknown.
The following summaries draw on these quantitative and qualitative
assessments to describe NMFS' conclusions regarding the status of each
steelhead ESU.
(1) Puget Sound
No estimates of historical (pre-1960s) abundance specific to the
Puget Sound ESU are available. Total run size for Puget Sound for the
early 1980s can be calculated from estimates in Light (1987) as about
100,000 winter steelhead and 20,000 summer steelhead. Light (1987)
provided no estimate of hatchery proportion specific to Puget Sound
streams. For Puget Sound and coastal Washington combined, Light (1987)
estimated that 70 percent of steelhead in ocean runs were of hatchery
origin; the percentage in escapement to spawning grounds would be
substantially lower due to differential harvest and hatchery rack
returns. Recent 5-year average natural escapements for streams with
adequate data range from less than 100 to 7,200, with corresponding
total run sizes of 550 to 19,800. Total recent run size for major
stocks in this ESU was greater than 45,000, with total natural
escapement of about 22,000.
Of the 21 independent stocks for which adequate escapement
information exists, 17 stocks have been declining and 4 increasing over
the available data series, with a range from 18 percent annual decline
(Lake Washington winter steelhead) to 7 percent annual increase
(Skykomish River winter steelhead). Eleven of these trends (nine
negative, two positive) were significantly different from zero. The two
basins producing the largest numbers of steelhead (Skagit and Snohomish
Rivers) both have overall upward trends.
Hatchery fish in this ESU are widespread, spawn naturally
throughout the region, and are largely derived from a single stock
(Chambers Creek). The proportion of spawning escapement comprised of
hatchery fish ranged from less than 1 percent (Nisqually River) to 51
percent (Morse Creek). In general, hatchery proportions are higher in
Hood Canal and the Strait of Juan de Fuca than in Puget Sound proper.
Most of the hatchery fish in this region originated from stocks
indigenous to the ESU, but are generally not native to local river
basins. The WDFW has provided information supporting substantial
temporal separation between hatchery and natural winter steelhead in
this ESU. Given the lack of strong trends in abundance for the major
stocks and the apparently limited contribution of hatchery fish to
production of the late-run winter stocks, most winter steelhead stocks
in the Puget Sound ESU appear to be naturally sustaining at this time.
However, there are clearly isolated problems with sustainability of
some steelhead runs in this ESU, notably Deer Creek summer steelhead
(although juvenile abundance for this stock increased in 1994) and Lake
Washington winter steelhead. Summer steelhead stocks within this ESU
are all small, occupy limited habitat, and most are subject to
introgression by hatchery fish.
NMFS concludes that the Puget Sound steelhead ESU is not presently
in danger of extinction, nor is it likely to become endangered in the
foreseeable
[[Page 41550]]
future. Despite this conclusion, NMFS has several concerns about the
overall health of this ESU and about the status of certain stocks
within the ESU. Recent trends in stock abundance are predominantly
downward, although this may be largely due to recent climate
conditions. Trends in the two largest stocks (Skagit and Snohomish
Rivers) have been upward. The majority of steelhead produced within the
Puget Sound region appear to be of hatchery origin, but most hatchery
fish are harvested and do not contribute to natural spawning
escapement. NMFS is particularly concerned that the majority of
hatchery production originates from a single stock (Chambers Creek).
The status of certain stocks within the ESU is also of concern,
especially the depressed status of most stocks in the Hood Canal area
and the steep declines of Lake Washington winter steelhead and Deer
Creek summer steelhead.
(2) Olympic Peninsula
No estimates of historical (pre-1960s) abundance specific to the
Olympic Peninsula ESU are available. Total run size for the major
stocks in the Olympic Peninsula ESU for the early 1980's can be
calculated from estimates in Light (1987) as about 60,000 winter
steelhead. Light (1987) provided no estimate of hatchery proportion for
these streams. For Puget Sound and coastal Washington together, Light
(1987) estimated that 70 percent of steelhead were of hatchery origin.
Recent 5-year average natural escapements for streams with adequate
data range from 250 to 6,900, with corresponding total run sizes of 450
to 19,700. Total recent (1989-1993 average) run size for major streams
in this ESU was about 54,000, with a natural escapement of 20,000 fish.
Of the 12 independent stocks for which adequate information existed
to compute trends, 7 were declining and 5 increasing over the available
data series, with a range from 8 percent annual decline to 14 percent
annual increase. Three of the downward trends were significantly
different from zero. Three of the four river basins producing the
largest numbers of natural fish had upward trends in basinwide total
numbers.
Hatchery fish are widespread and escaping to spawn naturally
throughout the region, with hatchery production largely derived from a
few parent stocks. Estimated proportions of hatchery fish in natural
spawning areas range from 16 percent (Quillayute River) to 44 percent
(Quinault River), with the two largest producers of natural fish
(Quillayute and Queets Rivers) having the lowest proportions. The WDFW
has provided information supporting substantial temporal separation
between hatchery and natural winter steelhead in this ESU. Given the
lack of strong trends in abundance and the apparently limited
contribution of hatchery fish to production of the late-run winter
stocks, most winter steelhead stocks in the Olympic Peninsula ESU
appear to be naturally sustaining at this time. However, there are
clearly isolated problems with sustainability of some winter steelhead
runs in this ESU, notably the Pysht/Independents stock, which has a
small population with a strongly declining trend over the available
data series, and the Quinault River stock, which has a declining trend
and substantial hatchery contribution to natural spawning.
NMFS concludes that the Olympic Peninsula steelhead ESU is not
presently in danger of extinction, nor is it likely to become
endangered in the foreseeable future. Despite this conclusion, NMFS has
several concerns about the overall health of this ESU and about the
status of certain stocks within the ESU. The majority of recent trends
are upward (including three of the four largest stocks), although
trends in several stocks are downward. These downward trends may be
largely due to recent climate conditions. There is widespread
production of hatchery steelhead within this ESU, largely derived from
a few parent stocks, which could increase genetic homogenization of the
resource despite management efforts to minimize introgression of the
hatchery gene pool into natural populations.
(3) Southwest Washington
No estimates of historical (pre-1960's) abundance specific to this
ESU are available. Recent 5-year average natural escapements for
individual tributaries with adequate data range from 150 to 2,300, with
the Chehalis River and its tributaries representing the bulk of
production. Total recent (5-year average) natural escapement for major
streams in this ESU was about 13,000.
All but 1 (Wynoochee River) of the 12 independent stocks have been
declining over the available data series, with a range from 7 percent
annual decline to 0.4 percent annual increase. Six of the downward
trends were significantly different from zero. For Washington streams,
these trends are for the late run ``wild'' component of winter
steelhead populations; Oregon data included all stock components. Most
of the Oregon trends are based on angler catch, and so may not reflect
trends in underlying population abundance. In general, stock condition
appears to be healthier in southwest Washington than in the lower
Columbia River Basin.
Hatchery fish are widespread and escaping to spawn naturally
throughout the region, largely from parent stocks from outside the ESU.
This could substantially change the genetic composition of the resource
despite management efforts to minimize introgression of the hatchery
gene pool into natural populations. Estimates of the proportion of
hatchery fish on natural spawning grounds range from 9 percent
(Chehalis, the largest producer of steelhead in the ESU) to 82 percent
(Clatskanie). Available information suggests substantial temporal
separation between hatchery and natural winter steelhead in this ESU;
however, some Washington stocks (notably lower Columbia River
tributaries) appear to have received substantial hatchery contributions
to natural spawning.
NMFS concludes that the Southwest Washington steelhead ESU is not
presently in danger of extinction, nor is it likely to become
endangered in the foreseeable future. Almost all stocks within this ESU
for which data exist have been declining in the recent past, although
this may be partly due to recent climate conditions. NMFS is very
concerned about the pervasive opportunity for genetic introgression
from hatchery stocks within the ESU and about the status of summer
steelhead in this ESU. There is widespread production of hatchery
steelhead within this ESU, largely from parent stocks from outside the
ESU. This could substantially change the genetic composition of the
resource despite management efforts to minimize introgression of the
hatchery gene pool into natural populations.
(4) Lower Columbia River
No estimates of historical (pre-1960's) abundance specific to this
ESU are available. Total run size for the major stocks in the lower
Columbia River (below Bonneville Dam, including the upper Willamette
ESU) for the early 1980's can be calculated from estimates in Light
(1987) as approximately 150,000 winter steelhead and 80,000 summer
steelhead. Light (1987) estimated that 75 percent of the total run
(summer and winter steelhead combined) was of hatchery origin. Recent
5-year average natural escapements for streams with adequate data range
from less than 100 to 1,100. Total recent run size for major streams in
this ESU was greater than 16,000, but this total includes only the few
basins for which estimates are available.
[[Page 41551]]
Of the 18 stocks for which adequate adult escapement trend data
exists, 11 have been declining and 7 increasing, with a range from 24
percent annual decline to 48 percent annual increase. Eight of these
trends (5 negative, 3 positive) were significantly different from zero.
Most of the data series for this ESU are short, beginning only in the
late 1970's to the mid-1980's. Thus, they may be heavily influenced by
short-term climate effects. Some of the Washington trends (notably
those for the Cowlitz and Kalama River Basins) have been influenced
(positively or negatively) by the 1980 eruption of Mount Saint Helens.
For Washington streams, these trends are for the late run ``wild''
component of winter steelhead populations; Oregon data included all
stock components. Most of the Oregon trends are based on angler catch,
and so may not reflect trends in underlying population abundance.
Hatchery fish are widespread, and many stray to spawn naturally
throughout the region. Most of the hatchery stocks used originated
primarily from stocks within the ESU, but many are not native to local
river basins. The WDFW has provided information supporting substantial
temporal separation between hatchery and natural winter steelhead in
this ESU; however, some Washington stocks (notably Kalama River winter
and summer steelhead) appear to have substantial hatchery contribution
to natural spawning. ODFW estimates of hatchery composition indicate a
range from about 30 percent (Sandy River and Tanner Creek winter
steelhead) to 80 percent (Hood River summer steelhead) hatchery fish in
spawning escapements. Estimates for Hood River winter steelhead range
from 0 percent (ODFW, 1995b) to greater than 40 percent (ODFW, 1995a).
NMFS concludes that the Lower Columbia River steelhead ESU is not
presently in danger of extinction, but is likely to become endangered
in the foreseeable future. The majority of stocks within this ESU for
which data exist have been declining in the recent past, but some have
been increasing strongly. However, the strongest upward trends are
either non-native stocks (Lower Willamette River and Clackamas River
summer steelhead) or stocks that are recovering from major habitat
disruption and are still at low abundance (mainstem and North Fork
Toutle River). NMFS is very concerned about the pervasive opportunity
for genetic introgression from hatchery stocks within the ESU and about
the status of summer steelhead in this ESU. Concerns about hatchery
influence are especially strong for summer steelhead and Oregon winter
steelhead stocks, where there appears to be substantial overlap in
spawning between hatchery and natural fish.
(5) Upper Willamette River
No estimates of historical (pre-1960's) abundance specific to this
ESU are available. Total recent 5-year average run size for this ESU
can be estimated from counts at Willamette Falls for the years 1989-
1993. Dam counts indicate that the late-run (``native'') winter
steelhead average run size was approximately 4,200, while early-run
winter and summer steelhead averaged 1,900 and 9,700 respectively.
Adequate angler catch data are available to derive approximate average
winter steelhead escapement for three tributaries: Mollala River, 2,300
(predominantly non-native); North Fork Santiam River, 2,000; South Fork
Santiam River, 550.
Total basin run-size or escapement estimates for both total winter
and late winter steelhead exhibit declines, while summer steelhead
estimates exhibit an increase. All of these basin-wide estimates have
exhibited large fluctuations. Of the three tributary winter steelhead
stocks for which adequate adult escapement information exists to
compute trends, two have been declining and one increasing, with a
range from 4.9 percent annual decline to 2.4 percent annual increase.
None of these trends were significantly different from zero.
Hatchery fish are widespread and escaping to spawn naturally
throughout the region. Both summer steelhead and early-run winter
steelhead have been introduced into the basin and escape to spawn
naturally in substantial numbers. Indigenous late-run winter steelhead
are also produced in the Santiam River Basin. Estimates of hatchery
contribution to winter steelhead escapements are available only for the
North Fork Santiam River and the Mollala River and are variable,
ranging from 14 percent (ODFW, 1995b) to 54 percent (ODFW, 1995a) on
the North Fork Santiam River. There is probably some temporal and
spatial separation in spawning between the early and late winter
stocks. While little information exists on the actual contribution of
hatchery fish to natural production, given the generally low numbers of
fish escaping to tributaries and the general declines in winter
steelhead abundance in the basin, NMFS has substantial concern that the
majority of natural winter steelhead populations in this ESU may not be
self-sustaining. All summer steelhead within the range of this ESU are
introduced from outside the area (i.e., they are non-native), so are
not considered as part of the ESU. Natural reproduction by these
introduced summer steelhead may be quite limited.
NMFS concludes that the Upper Willamette steelhead ESU is not
presently in danger of extinction, nor is it likely to become
endangered in the foreseeable future. While historical information
regarding this ESU is lacking, geographic range and historical
abundance are believed to have been relatively small compared to other
ESUs, and current production probably represents a larger proportion of
historical production than is the case in other Columbia River Basin
ESUs. NMFS is concerned about the pervasive opportunity for genetic
introgression from hatchery stocks within the ESU, as well as the
potential ecological interactions between introduced stocks and native
stocks.
(6) Oregon Coast
No estimates of historical abundance specific to this ESU are
available, except for counts at Winchester Dam on the North Umpqua
River and angler catch records beginning in 1953. Estimated total run
size for the major stocks on the Oregon Coast (including areas south of
Cape Blanco) for the early 1980s are given by Light (1987) as
approximately 255,000 winter steelhead and 75,000 summer steelhead. Of
these, 69 percent of winter and 61 percent of summer steelhead were of
hatchery origin, resulting in estimated naturally-produced run sizes of
79,000 winter and 29,000 summer steelhead. Recent 5-year average total
(natural and hatchery) run sizes for streams with adequate data range
from 250 to 15,000, corresponding to escapements from 200 to 12,000.
Total recent (5-year average) run size for major streams in this ESU
was approximately 129,000 (111,000 winter, 18,000 summer), with a total
escapement of 96,000 (82,000 winter, 14,000 summer). These totals do
not include all streams in the ESU, so they may underestimate total ESU
run size and escapements.
Adequate adult escapement information was available to compute
trends for 42 independent stocks within this ESU. Of these, 36 data
series exhibit declines and six exhibit increases over the available
data series, with a range from 12 percent annual decline (Drift Creek
on the Siletz River) to 16 percent annual increase (North Fork Coquille
River). Twenty (18 decreasing, 2 increasing) of these trends were
significantly different from zero. Upward trends were only found in the
southernmost portion of the ESU, from
[[Page 41552]]
Siuslaw Bay south. In contrast, longer-term trends in angler catch
using data from the early 1950's to the present generally were
increasing. This may reflect long-term stability of populations or may
be an artifact of long-term increases in statewide fishing effort
coupled with the differences in bias correction of catch summaries
before and after 1970.
Hatchery fish are widespread and escaping to spawn naturally
throughout the region. Most of the hatchery stocks used in this region
originated from stocks indigenous to the ESU, but many are not native
to local river basins. The ODFW estimates of hatchery composition for
winter steelhead escapements are high in many streams, ranging from 10
percent (North Umpqua River) to greater than 80 percent (Drift Creek on
the Alsea River and Tenmile Creek south of Umpqua Bay). For summer
steelhead, hatchery composition (where reported) ranged from 38 percent
(South Umpqua River) to 90 percent (Siletz River). Several summer
steelhead stocks have been introduced to rivers with no native summer
runs. Overall, about half of the stocks in this ESU for which NMFS has
information have hatchery composition in excess of 50 percent. Few
stocks in the ESU are documented to have escapements above 1,000 fish
and no significant decline; most of these are in the southern portion
of the ESU and have high hatchery influence. While little information
exists on the actual contribution of hatchery fish to natural
production, given the substantial presence of hatchery fish in the few
stocks that are relatively abundant and stable or increasing, NMFS is
concerned that the majority of natural steelhead populations in this
ESU may not be self-sustaining.
NMFS concludes that the Oregon Coast steelhead ESU is not presently
in danger of extinction, but is likely to become endangered in the
foreseeable future. Most steelhead populations within this ESU have
been declining in the recent past (although this may be partly due to
recent climate conditions), with increasing trends restricted to the
southernmost portion (south of Siuslaw Bay). NMFS is very concerned
about the pervasive opportunity for genetic introgression from hatchery
stocks within the ESU, as well as the potential ecological interactions
between introduced stocks and native stocks.
(7) Klamath Mountains Province
NMFS has previously published a proposal to list this ESU as
threatened under the ESA (60 FR 14253, March 16, 1995). Although
historical trends in overall abundance within the ESU are not clearly
known, NMFS believes there has been a substantial replacement of
natural fish with hatchery-produced fish. While absolute abundance
remains fairly high, since about 1970, trends in abundance have been
downward in most steelhead populations for which NMFS has data within
the ESU, and a number of populations are considered by various agencies
and groups to be at some risk of extinction. Declines in summer
steelhead populations are of particular concern. Most natural
populations of steelhead within the area experience a substantial
infusion of naturally spawning hatchery fish each year.
Risk analyses for this and other ESUs are unusually difficult due
to the paucity of abundance data and, where data are available, the
possible biases associated with particular data sets (e.g., angler
catch records). Also, the Klamath Mountains Province status review was
the first NMFS assessment in which the issue of naturally spawning
hatchery fish and the questions they raise about the sustainability of
natural populations was an important consideration. NMFS will continue
to seek additional information and pursue assessments with Federal,
state, and tribal fisheries managers that should help clarify the risk
faced by Klamath Mountains Province Steelhead. Hence, NMFS will make a
final determination on the status of this ESU concurrently with final
listing determinations on all west coast steelhead ESUs.
(8) Northern California
Historical (pre-1960's) abundance information specific to this ESU
is available from dam counts in the upper Eel River (Cape Horn Dam--
annual average of 4,400 adult steelhead in the 1930's; McEwan &
Jackson, 1996), the South Fork Eel River (Benbow Dam--annual average of
19,000 adult steelhead in the 1940's; McEwan & Jackson, 1996), and the
Mad River (Sweasey Dam--annual average of 3,800 adult steelhead in the
1940's; Murphy & Shapovalov, 1951; CDFG, 1994).
In the mid-1960's, CDFG (1965) estimated that steelhead spawning
populations for many rivers in this ESU totaled 198,000 fish. Estimated
statewide total run size for the major stocks in California in the
early 1980's was given by Light (1987) as approximately 275,000 fish.
Of this total, 22 percent were estimated to be of hatchery origin,
resulting in a naturally-produced run size of 215,000 steelhead
statewide. Roughly half of this production was thought to be in the
Klamath River Basin (including the Trinity River), so the total natural
production for all ESUs south of the Klamath River was probably on the
order of 100,000 adults.
The only current run-size estimates for this area are dam counts on
the Eel River (Cape Horn Dam) and summer steelhead snorkel surveys in a
few tributaries that provide no total abundance estimate. Statewide
adult summer steelhead abundance is estimated at about 2,000 adults
(McEwan & Jackson, 1996). While no overall recent abundance estimate
for this ESU exists, the substantial declines in run size from historic
levels at major dams in the region indicate a probable similar overall
decline in abundance from historical levels.
Adequate adult escapement information was available to compute
trends for seven stocks (Redwood Creek, Mad River [winter and summer
runs], the mainstem, Middle Fork, and South Fork of the Eel River, and
the South Fork of the Van Duzen River). Of these, five data series
exhibit declines and two exhibit increases over the available data
series, ranging from a 5.8-percent annual decline (mainstem Eel River)
to a 3.5-percent annual increase (south Fork of the Van Duzen River).
Three (all decreasing) of these trends were significantly different
from zero. For one long-term data set (Eel River, Cape Horn Dam
counts), a separate trend for the last 21 years (1971-1991) was
calculated for comparison. The full-series trend showed a significant
decline, but the recent data showed a lesser, non-significant decline,
suggesting that the major stock decline occurred prior to 1970.
State hatchery planting records indicate that large numbers of out-
of-basin hatchery fish are planted throughout this ESU and are allowed
to spawn naturally throughout the region. According to McEwan and
Jackson (1996), ``despite the large number of hatchery smolts released,
steelhead runs in north coast drainages are comprised mostly of
naturally produced fish.'' There is little information on the actual
contribution of hatchery fish to natural spawning, and little
information on present total run sizes for this ESU. However, given the
preponderance of significant negative trends in the available data
series, there is concern that steelhead populations in this ESU may not
be self-sustaining.
NMFS concludes that the Northern California steelhead ESU is not
presently in danger of extinction, but is likely to become endangered
in the foreseeable future. Population abundances are very low relative
to historical estimates (1930's dam counts),
[[Page 41553]]
and recent trends are downward in stocks for which data exist, except
for two small summer steelhead stocks. Summer steelhead abundance is
very low. The abundance of introduced Sacramento squawfish
(Ptychocheilus grandis), a known predator of salmonids, in the Eel
River is also a concern. For certain rivers (particularly the Mad
River), NMFS is concerned about the influence of hatchery stocks, both
in terms of genetic introgression and potential ecological interactions
between introduced stocks and native stocks.
(9) Central California Coast
Only two estimates of historical (pre-1960's) abundance specific to
this ESU are available: an average of about 500 adults in Waddell Creek
in the 1930's and early 1940's (Shapovalov & Taft, 1954), and an
estimate of 20,000 steelhead in the San Lorenzo River before 1965
(Johnson, 1964). In the mid-1960's, CDFG (1965) estimated 94,000
steelhead spawning in many rivers of this ESU, including 50,000 and
19,000 fish in the Russian and San Lorenzo Rivers, respectively. NMFS
has comparable recent estimates for only the Russian (approximately
7,000 fish) and San Lorenzo (approximately 500 fish) Rivers. These
estimates indicate that recent total abundance of steelhead in these
two rivers is less than 15 percent of their abundance 30 years ago.
Additional recent estimates for several other streams (Lagunitas Creek,
Waddell Creek, Scott Creek, San Vincente Creek, Soquel Creek, and Aptos
Creek) indicate individual run sizes are 500 fish or less; however, no
recent estimates of total run size exist for this ESU. McEwan and
Jackson (1996) noted that steelhead in most streams tributary to San
Francisco and San Pablo Bays have been extirpated. Small ``fair to
good'' runs of steelhead apparently occur in coastal Marin County
tributaries.
Adequate adult escapement information was not available to compute
trends for any stocks within this ESU. However, general trends can be
inferred from the comparison of 1960's and 1990's abundance estimates
provided above, which indicate substantial rates of decline in the two
main steelhead stocks (Russian and San Lorenzo Rivers) within this ESU.
The principal hatchery production in this ESU is from Warm Springs
Hatchery on the Russian River and the Monterey Bay Salmon and Trout
Project (Big Creek Hatchery off Scott Creek and other facilities).
There are other small private and cooperative programs producing
steelhead within this ESU. Most of the hatchery stocks used in this
region originated from stocks indigenous to the ESU, but many are not
native to local river basins. Little information is available regarding
the actual contribution of hatchery fish to natural spawning, and
little information on present run sizes or trends for this ESU exists.
However, given the substantial rates of declines for those stocks where
data do exist, it is likely that the majority of natural production in
this ESU is not self-sustaining.
NMFS concludes that the Central California Coast steelhead ESU is
presently in danger of extinction. The southernmost portion of the ESU
(south of Scott and Waddell Creeks, including one of two major rivers
within the ESU) and the portion within San Francisco and San Pablo Bays
appear to be at highest risk. In the northern coastal portion of the
ESU, steelhead abundance in the Russian River has been reduced roughly
sevenfold since the mid-1960's, but abundance in smaller streams
appears to be stable at low levels. There is particular concern for
sedimentation and channel restructuring due to floods, apparently
resulting in part from poor land management practices.
(10) South/Central California Coast
Historical estimates of steelhead abundance are available for a few
streams in this region. In the mid-1960's, CDFG (1965) estimated a
total of 27,750 steelhead spawning in many rivers of this ESU. Recent
estimates for those rivers where comparative abundance information is
available show a substantial decline during the past 30 years. In
contrast to the CDFG (1965) estimates, McEwan and Jackson (1996)
reported runs ranging from 1,000 to 2,000 in the Pajaro River in the
early 1960's, and Snider (1983) estimated escapement of about 3,200
steelhead for the Carmel River for the 1964-1975 period. No recent
estimates for total run size exist for this ESU; however, recent run-
size estimates are available for five streams (Pajaro River, Salinas
River, Carmel River, Little Sur River, and Big Sur River). The total of
these estimates is less than 500 fish, compared with a total of 4,750
for the same streams in 1965, which suggests a substantial decline for
the entire ESU from 1965 levels.
Adequate adult escapement information was available to compute a
trend for only one stock within this ESU (Carmel River above San
Clemente Dam). This data series shows a significant decline of 22
percent per year from 1963 to 1993, with a recent 5-year average count
of only 16 adult steelhead at the dam. General trends can be inferred
from the comparison of 1960's and 1990's abundance estimates provided
above.
Presently, there is little hatchery production within this ESU.
There are small private and cooperative programs producing steelhead
within this ESU, as well as one captive broodstock program intended to
conserve the Carmel River steelhead strain (McEwan & Jackson, 1996).
Most of the hatchery stocks used in this region originated from stocks
indigenous to the ESU, but many are not native to local river basins.
Little information exists regarding the actual contribution of hatchery
fish to natural spawning, and little information on present total run
sizes or trends are available for this ESU. However, given the
substantial reductions from historical abundance or recent negative
trends in the stocks for which data does exist, it is likely that the
majority of natural production in this ESU is not self-sustaining.
NMFS concludes that the South-Central California Coast steelhead
ESU is presently in danger of extinction. Total abundance is extremely
low, and most stocks for which NMFS has data in the ESU show recent
downward trends. There is also concern about the genetic effects of
widespread stocking of rainbow trout.
(11) Southern California
Historically, steelhead occurred naturally south into Baja
California. Estimates of historical (pre-1960's) abundance for several
rivers in this ESU are available: Santa Ynez River, before 1950, 20,000
to 30,000 (Shapovalov & Taft, 1954; CDFG, 1982; Reavis, 1991; Titus et
al., in press); Ventura River, pre-1960, 4,000 to 6,000 (Clanton &
Jarvis, 1946; CDFG, 1982; AFS, 1991; Hunt et al., 1992; Henke, 1994;
Titus et al., in press); Santa Clara River, pre-1960, 7,000 to 9,000
(Moore, 1980; Comstock, 1992; Henke, 1994); Malibu Creek, pre-1960,
1,000 (Nehlsen et al., 1991; Reavis, 1991). ln the mid-1960's, CDFG
(1965) estimated steelhead spawning populations for smaller tributaries
in San Luis Obispo County as 20,000 fish; however, no estimates for
streams further south were provided.
The present estimated total run size for six streams (Santa Ynez
River, Gaviota Creek, Ventura River, Matilija Creek, Santa Clara River,
Malibu Creek) in this ESU are summarized in Titus et al. (in press),
and all are less than 200 adults. Titus et al. (in press) concluded
that populations have been extirpated from all streams south of Ventura
County, with the exception of Malibu Creek in Los Angeles County. While
there are no comprehensive stream
[[Page 41554]]
surveys conducted for steelhead trout occurring in streams south of
Malibu Creek, there continues to be anecdotal observations of steelhead
in rivers as far south as the Santa Margarita River, San Diego County,
in years of substantial rainfall (Barnhart, 1986; Higgins, 1991; McEwan
and Jackson, 1996). Titus et al. (in press) cited extensive loss of
steelhead habitat due to water development, including impassable dams
and dewatering.
No time series of data are available within this ESU to estimate
population trends. Titus et al. (in press) summarized information for
steelhead populations based on historical and recent survey
information. Of the populations south of San Francisco Bay (including
part of the Central California Coast ESU) for which past and recent
information was available, 20 percent had no discernable change, 45
percent had declined, and 35 percent were extinct. Percentages for the
counties comprising this ESU show a very high percentage of declining
and extinct populations.
The influence of hatchery practices on this ESU is not well
documented. In some populations, there may be genetic introgression
from past steelhead plants and from planting of rainbow trout (Nielsen
1991). Habitat fragmentation and population declines resulting in
small, isolated populations also pose genetic risk from inbreeding,
loss of rare alleles, and genetic drift.
NMFS concludes that the Southern California steelhead ESU is
presently in danger of extinction. Steelhead have already been
extirpated from much of their historical range in this ESU. There is
also concern about the genetic effects of widespread stocking of
rainbow trout.
(12) Central Valley
Historical abundance estimates are available for some stocks within
this ESU, but no overall estimates are available prior to 1961, when
Hallock et al. (1961) estimated a total run size of 40,000 steelhead in
the Sacramento River, including San Francisco Bay. In the mid-1960's,
CDFG (1965) estimated steelhead spawning populations for the rivers in
this ESU, totaling almost 27,000 fish. Limited data exist on recent
abundance for this ESU. The present total run size for this ESU based
on dam counts, hatchery returns, and past spawning surveys is probably
less than 10,000 fish. Both natural and hatchery runs have declined
since the 1960's. Counts at Red Bluff Diversion Dam averaged 1,400 fish
over the last 5 years, compared with runs in excess of 10,000 fish in
the late 1960's. Recent run-size estimates for the hatchery produced
American River stock average less than 1,000 fish, compared to 12,000
to 19,000 in the early 1970's (McEwan & Jackson, 1996).
Adequate adult escapement information was available to compute a
trend for only one stock within this ESU (Sacramento River above Red
Bluff Diversion Dam). Fish passing over this dam are primarily (70 to
90 percent) of hatchery origin (CDFG, 1995; McEwan & Jackson, 1996).
This data series shows a significant decline of 9 percent per year from
1966 to 1992. McEwan and Jackson (1996) cite substantial declines in
hatchery returns within the basin as well. The majority of native,
natural steelhead production in this ESU occurs in upper Sacramento
River tributaries (Antelope, Deer, Mill, and other Creeks) below Red
Bluff Diversion Dam, but these populations are nearly extirpated. The
American, Feather, and Yuba (and possibly the upper Sacramento and
Mokelumne) Rivers also have naturally-spawning populations (CDFG,
1995), but these populations have had substantial hatchery influence
and their ancestry is not clearly known. The Yuba River had an
estimated run size of 2,000 in 1984. Recent run size estimates for the
Yuba River are unknown, but the population appears to be stable and
supports a sport fishery (McEwan & Jackson, 1996). However, the status
of native, natural fish in this stock is unknown. This stock has been
influenced by Feather River Hatchery fish, and biologists familiar with
the stock report that the Yuba River supports almost no natural
production of steelhead (Hallock, 1989). However, CDFG (1995) asserted
that ``a substantial portion of the returning adults are progeny of
naturally spawning adults from the Yuba River.'' This stock currently
receives no hatchery steelhead plants and is managed as a naturally
sustained population (CDFG, 1995; McEwan & Jackson, 1996).
In the San Joaquin River Basin, there is little available historic
or recent information on steelhead distribution or abundance. According
to McEwan and Jackson (1996), there are reports of a small remnant
steelhead run in the Stanislaus River. Also, steelhead were observed in
the Tuolumne River in 1983, and large rainbow trout (possibly
steelhead) have been observed at Merced River Hatchery recently.
NMFS concludes that the Central Valley steelhead ESU is presently
in danger of extinction. Steelhead have already been extirpated from
most of their historical range in this ESU. Habitat concerns in this
ESU focus on the widespread degradation, destruction, and blockage of
freshwater habitats within the region, and the potential results of
continuing habitat destruction and water allocation problems. NMFS is
also very concerned about the pervasive opportunity for genetic
introgression from hatchery stocks within the ESU because of the
widespread production of hatchery steelhead, and the potential
ecological interactions between introduced stocks and native stocks.
(13) Middle Columbia River Basin
Estimates of historical (pre-1960's) abundance indicate that the
total historical run size for this ESU might have been in excess of
300,000. Total run sizes for the major stocks in the upper Columbia
River (above Bonneville Dam, including the Upper Columbia River, Snake
River Basin, and parts of the Southwest Washington and Lower Columbia
River ESUs) for the early 1980's were estimated by Light (1987) as
approximately 4,000 winter steelhead and 210,000 summer steelhead.
Based on dam counts for this period, the Middle Columbia River ESU
represented the majority of this total run estimate, so the run
returning to this ESU was probably somewhat below 200,000 at that time.
Light (1987) estimated that 80 percent of the total Columbia River
Basin run (summer and winter steelhead combined) above Bonneville Dam
was of hatchery origin. The most recent 5-year average run size was
142,000, with a naturally-produced component of 39,000. These data
indicate approximately 74 percent hatchery fish in the total run to
this ESU. Recent escapement or run size estimates exist for only five
basins in this ESU. For the main Deschutes River (counted at Sherars
Falls), total recent (5-year average) run size was approximately
11,000, with a natural escapement of 3,000. Hatchery escapement to
spawning grounds (calculated by subtracting Pelton Ladder and other
hatchery returns from the counts at Sherars Falls) has averaged about
4,000 adults over the last five brood years (BPA 1992). For the Warm
Springs River (steelhead passing above Warm Springs NFH), escapement
has averaged 150 adults over the last 5 years. In the Umatilla River
(counts at Three Mile Dam) escapement has averaged 1,700 adults over
the last 5 years. In the Yakima River, total escapement has averaged
1,300 adults, with a natural escapement of 1,200 adults, over the last
5 years. In addition to these estimates, ODFW (1995a) suggested that 5
sub-basins of the John Day River each have runs in excess of 1,000, so
the total run size for the John
[[Page 41555]]
Day River is probably in excess of 5,000 fish.
Stock trend data are available for various basins from dam counts,
spawner surveys, and angler catch. Of the 14 independent stock indices
for which trends could be computed, 10 have been declining and 4
increasing over the available data series, with a range from 20 percent
annual decline to 14 percent annual increase. Eight of these trends
(seven negative, one positive) were significantly different from zero.
Of the major basins, the Yakima, Umatilla, and Deschutes Rivers show
upward overall trends, although all tributary counts in the Deschutes
River are downward and the Yakima River is recovering from extremely
low abundance in the early 1980's. The John Day River probably
represents the largest native, natural spawning stock in the ESU, and
combined spawner surveys for the John Day River have been declining at
a rate of about 15 percent per year since 1985. However, estimates of
total run size for the ESU based on differences in counts at dams show
an overall increase in steelhead abundance, with a relatively stable
naturally-produced component.
Hatchery fish are widespread and straying to spawn naturally
throughout the region. Hatchery production in this ESU is derived
primarily from within-basin stocks. Recent estimates of the proportion
of natural spawners with hatchery origin range from low (Yakima River,
Walla Walla River, John Day River) to moderate (Umatilla River,
Deschutes River). Little information is available on the actual
contribution of hatchery production to natural spawning.
NMFS concludes that the Middle Columbia steelhead ESU is not
presently in danger of extinction, but has reached no conclusion
regarding its likelihood of becoming endangered in the foreseeable
future. NMFS remains concerned about the status of this ESU and will
carefully evaluate conservation measures affecting this ESU and
continue monitoring its status during the period between this proposed
rule and publication of a final rule. There is particular concern about
Yakima River stocks and winter steelhead stocks. Winter steelhead are
reported within this ESU only in the Klickitat River and Fifteenmile
Creek. No abundance information exists for winter steelhead in the
Klickitat River, but they have been declining in abundance in
Fifteenmile Creek. Total steelhead abundance in the ESU appears to have
been increasing recently, but the majority of natural stocks for which
NMFS has data within this ESU have been declining, including those in
the John Day River, which is the largest producer of native, natural
steelhead. NMFS is very concerned about the pervasive opportunity for
genetic introgression from hatchery stocks within the ESU. There is
widespread production of hatchery steelhead within this ESU, but
largely based on within basin stocks. Estimated proportion of hatchery
fish on spawning grounds ranges from low (Yakima River, Walla Walla
River, John Day River) to moderate (Umatilla River, Deschutes River).
(14) Upper Columbia River Basin
Estimates of historical (pre-1960s) abundance specific to this ESU
are available from fish counts at dams. Counts at Rock Island Dam from
1933 to 1959 averaged 2,600 to 3,700, suggesting a pre-fishery run size
in excess of 5,000 adults for tributaries above Rock Island Dam
(Chapman et. al., 1994). However, runs may already have been depressed
by lower Columbia River fisheries at this time. Recent 5-year (1989-93)
average natural escapements are available for two stock units:
Wenatchee River, 800 steelhead, and Methow and Okanogan Rivers, 450
steelhead. Recent average total escapement for these stocks were 2,500
and 2,400, respectively. Average total run size at Priest Rapids Dam
for the same period was approximately 9,600 adult steelhead.
Trends in total (natural and hatchery) adult escapement are
available for the Wenatchee River (2.6 percent annual increase, 1962-
1993) and the Methow and Okanogan Rivers combined (12 percent annual
decline, 1982-93). These two stocks represent most of the escapement to
natural spawning habitat within the range of the ESU; the Entiat River
also has a small spawning run (WDF et al., 1993).
Hatchery fish are widespread and escaping to spawn naturally
throughout the region. The hatchery stock used in this region
originated from stocks indigenous to the ESU during the Grand Coulee
Fish Maintenance Project, but represents a blend of fish from all
basins within the ESU (and from areas above Grand Coulee Dam). Spawning
escapement is strongly dominated by hatchery production, with recent
contributions averaging 65 percent (Wenatchee River) to 81 percent
(Methow and Okanogan Rivers). The WDFW estimated adult replacement
ratios of only 0.3:1.0 in the Wenatchee River and 0.25:1.0 in the
Entiat River, and concluded that both these stocks and the Methow/
Okanogan stock are not self-sustaining without substantial hatchery
production.
NMFS concludes that the Upper Columbia steelhead ESU is presently
in danger of extinction. While total abundance of populations within
this ESU has been relatively stable or increasing, this appears to be
true only because of major hatchery production programs. Estimates of
the proportion of hatchery fish in spawning escapement are 65 percent
(Wenatchee River) and 81 percent (Methow and Okanogan Rivers). The
major concern for this ESU is the clear failure of natural stocks to
replace themselves. NMFS is very concerned about problems of genetic
homogenization due to hatchery supplementation within the ESU.
Significant concern also exists regarding the apparent high harvest
rates on steelhead smolts in rainbow trout fisheries and the
degradation of freshwater habitats within the region.
(15) Snake River Basin
No estimates of historical (pre-1960's) abundance specific to this
ESU are available. Light (1987) estimated that 80 percent of the total
Columbia River Basin run (summer and winter steelhead combined) above
Bonneville Dam was of hatchery origin. All steelhead in the Snake River
Basin are summer steelhead, which for management purposes are divided
into ``A-run'' and ``B-run'' steelhead. Each has several life history
differences including spawning size, run timing, and habitat type.
Although there is little information for most stocks within this ESU,
there are recent run-size and/or escapement estimates for several
stocks. Total recent-year average (1990-1994) escapement above Lower
Granite Dam was approximately 71,000, with a natural component of 9,400
(7,000 A-run and 2,400 B-run). Run-size estimates are available for
only a few tributaries within the ESU, all with small populations.
The aggregate trend in abundance for this ESU (indexed at Lower
Granite Dam) has been upward since 1975, although natural escapement
has been declining during the same period. However, the aggregate trend
has been downward (with wide fluctuations) over the past 10 years,
recently reaching levels below those observed at Ice Harbor Dam in the
early 1960's. Naturally-produced escapement has declined sharply in the
last ten years. Adult abundance trend information is available for
several individual stocks from a variety of sources, including spawner
surveys, dam counts, and angler catch. Of the thirteen stock indices
(excluding the Lower Granite
[[Page 41556]]
Dam counts discussed above) for which sufficient adequate information
exists to compute trends, nine have been declining and four increasing
over the available data series, with a range from 30 percent annual
decline to a 4 percent annual increase. Four of these trends (all
negative) were significantly different from zero. In addition to these
adult abundance data, the focus of IDFG's steelhead monitoring program
is juvenile (parr) surveys in areas designated as ``wild'' (i.e., sites
with limited hatchery influence) as well as in natural production
areas. Summaries in Leitzinger and Petrosky (in press) show declines in
average parr density over the past 7 or 8 years for both A- and B-run
steelhead in both wild and natural production areas. From 1985 to 1993,
estimates of mean percent of rated parr carrying capacity for these
surveys ranged from as low as 11.2 percent (wild-production B-run) to
62.1 percent (wild-production A-run). The U.S. v. Oregon Technical
Advisory Committee found that A-run steelhead densities were closer to
rated capacities than were B-run steelhead; it noted that ``percent
carrying capacity indicates that all surveyed areas are underseeded''
(TAC, 1991).
Hatchery fish are widespread and escaping to spawn naturally
throughout the region. During the past five years, an average of 86
percent of steelhead passing above Lower Granite Dam were of hatchery
origin. Only two hatchery composition estimates are available for
individual stocks: 0 percent for Joseph Creek (Grande Ronde River), and
57 percent for the Tucannon River. In general, there are wild
production areas with limited hatchery influence remaining in the
Selway River, lower Clearwater River, Middle and South Forks of the
Salmon River, and the lower Salmon River (Leitzinger & Petrosky, in
press). In other areas, such as the upper Salmon River, there appears
to be little or no natural production of locally-native steelhead
(IDFG, 1995). Given the relatively low natural run sizes to individual
streams for which estimates are available, the declines in natural
returns at Lower Granite Dam and in parr density estimates, and the
widespread presence of hatchery fish, NMFS concludes that the majority
of natural steelhead populations in this ESU are probably not self-
sustaining at this time.
NMFS concludes that the Snake River Basin steelhead ESU is not
presently in danger of extinction, but is likely to become endangered
in the foreseeable future. While total run size (hatchery and natural)
has increased since the mid-1970's, there has been a severe recent
decline in natural run size. The majority of natural stocks for which
adequate data exists within this ESU have been declining. Parr
densities in natural production areas have been substantially below
estimated capacity in recent years. Downward trends and low parr
densities indicate a particularly severe problem for B-run steelhead,
the loss of which would substantially reduce life-history diversity
within this ESU. NMFS is very concerned about the pervasive opportunity
for genetic introgression from hatchery stocks within the ESU. There is
widespread production of hatchery steelhead within this ESU. The total
Snake River steelhead run at Lower Granite Dam is estimated to average
86 percent hatchery fish in recent years. Estimates of proportion of
hatchery fish in spawning escapement for tributaries range from 0
percent (Joseph Creek) to above 80 percent (upper Salmon River, IDFG,
1995).
Existing Protective Efforts
Under Sec. 4(b)(1)(A) of the ESA, the Secretary of Commerce is
required to make listing determinations solely on the basis of the best
scientific and commercial data available and after taking into account
efforts being made to protect a species. During the status review for
west coast steelhead, NMFS reviewed an array of protective efforts for
steelhead and other salmonids, ranging in scope from regional
strategies to local watershed initiatives. NMFS has summarized some of
the major efforts in a document entitled ``Steelhead Conservation
Efforts: A Supplement to the Notice of Determination for West Coast
Steelhead under the Endangered Species Act.'' This document is
available upon request (see ADDRESSES section).
Despite numerous efforts to halt and reverse declining trends in
west coast steelhead, it is clear that the status of many native,
naturally-reproducing populations has continued to deteriorate. NMFS
therefore believes it highly likely that past efforts and programs to
address the conservation needs of these stocks have proven inadequate,
including efforts to reduce mortalities and improve the survival of
these stocks through all stages of their life cycle. Important factors
include the continued decline in the productivity of freshwater habitat
for a wide variety of reasons, significant potential negative impacts
from interactions with hatchery stocks, overfishing, and natural
environmental variability.
While NMFS recognizes that many of the ongoing protective efforts
are likely to promote the conservation of steelhead and other
salmonids, in the aggregate, they do not achieve steelhead conservation
at a scale that is adequate to protect and conserve ESUs. NMFS believes
that most existing efforts lack some of the critical elements needed to
provide a high degree of certainty that the efforts will be successful.
These elements include: (1) Identification of specific factors for
decline; (2) immediate measures required to protect the best remaining
populations and habitats and priorities for restoration activities; (3)
explicit and quantifiable objectives and timelines; and (4) monitoring
programs to determine the effectiveness of actions, including methods
to measure whether recovery objectives are being met.
The best available scientific information on the biological status
of the species supports a proposed listing of 10 steelhead ESUs under
the ESA (see Proposed Determination). NMFS concludes that existing
protective efforts are inadequate to alter the proposed determination
of threatened or endangered for these 10 steelhead ESUs. However,
during the period between publication of this proposed rule and
publication of a final rule, NMFS will continue to solicit information
regarding protective efforts (see Public Comments Solicited) and will
work with Federal, state and tribal fisheries managers to evaluate the
efficacy of the various salmonid conservation efforts. If, during this
process, NMFS determines that existing protective efforts are likely to
avert extinction and provide for the recovery of a steelhead ESU(s),
NMFS will modify this listing proposal.
Summary of Factors Affecting the Species
Section 2(a) of the ESA states that various species of fish,
wildlife, and plants in the United States have been rendered extinct as
a consequence of economic growth and development untempered by adequate
concern for ecosystem conservation. Section 4(a)(1) of the ESA and the
listing regulations (50 CFR part 424) set forth procedures for listing
species. NMFS must determine, through the regulatory process, if a
species is endangered or threatened based upon any one or a combination
of the following factors: (1) The present or threatened destruction,
modification, or curtailment of its habitat or range; (2)
overutilization for commercial, recreational, scientific, or education
purposes; (3) disease or predation; (4) inadequacy of existing
regulatory mechanisms; or (5) other natural or human-made factors
affecting its continued existence.
[[Page 41557]]
NMFS has prepared a supporting document which addresses the factors
that have led to the decline of this species entitled ``Factors for
Decline: A supplement to the notice of determination for West Coast
steelhead.'' This report, available upon request (see ADDRESSES
section), concludes that all of the factors identified in section
4(a)(1) of the ESA have played a role in the decline of the species.
The report identifies destruction and modification of habitat,
overutilization for recreational purposes, and natural and human-made
factors as being the primary reasons for the decline of west coast
steelhead. The following discussion summarizes findings regarding
factors for decline across the range of west coast steelhead. While
these factors have been treated here in general terms, it is important
to underscore that impacts from certain factors are more acute for
specific ESUs. For example, impacts from hydropower development are
more pervasive for ESUs in the upper Columbia River Basin than for some
coastal ESUs.
Steelhead on the west coast of the United States have experienced
declines in abundance in the past several decades as a result of
natural and human factors. Forestry, agriculture, mining, and
urbanization have degraded, simplified, and fragmented habitat. Water
diversions for agriculture, flood control, domestic, and hydropower
purposes (especially in the Columbia River and Sacramento-San Joaquin
Basins) have greatly reduced or eliminated historically accessible
habitat. Studies indicate that in most western states, about 80 to 90
percent of the historic riparian habitat has been eliminated. Further,
it has been estimated that during the last 200 years, the lower 48
states have lost approximately 53 percent of all wetlands and the
majority of the rest are severely degraded. Washington and Oregon's
wetlands are estimated to have diminished by one-third, while
California has experienced a 91-percent loss of its wetland habitat.
Loss of habitat complexity has also contributed to the decline of
steelhead. For example, in national forests in Washington, there has
been a 58-percent reduction in large, deep pools due to sedimentation
and loss of pool-forming structures such as boulders and large wood.
Similarly, in Oregon, the abundance of large, deep pools on private
coastal lands has decreased by as much as 80 percent. Sedimentation
from land use activities is recognized as a primary cause of habitat
degradation in the range of west coast steelhead.
Steelhead support an important recreational fishery throughout
their range. During periods of decreased habitat availability (e.g.,
drought conditions or summer low flow when fish are concentrated), the
impacts of recreational fishing on native anadromous stocks may be
heightened. Steelhead are not generally targeted in commercial
fisheries. However, high seas driftnet fisheries in the past may have
contributed slightly to a decline of this species in local areas, but
this could not be solely responsible for the large declines in
abundance observed along most of the Pacific coast over the past
several decades.
Introductions of non-native species and habitat modifications have
resulted in increased predator populations in numerous river systems,
thereby increasing the level of predation experienced by salmonids.
Predation by marine mammals is also of concern in areas experiencing
dwindling steelhead runsizes. However, salmon and marine mammals have
coexisted for thousands of years and most investigators consider
predation an insignificant contributing factor to the large declines
observed in west coast steelhead populations.
Natural climatic conditions have served to exacerbate the problems
associated with degraded and altered riverine and estuarine habitats.
Persistent drought conditions have reduced already limited spawning,
rearing and migration habitat. Further, climatic conditions appear to
have resulted in decreased ocean productivity which, during more
productive periods, may help (to a small degree) offset degraded
freshwater habitat conditions.
In an attempt to mitigate the loss of habitat, extensive hatchery
programs have been implemented throughout the range of steelhead on the
West Coast. While some of these programs have been successful in
providing fishing opportunities, the impacts of these programs on
native, naturally-reproducing stocks are not well understood.
Competition, genetic introgression, and disease transmission resulting
from hatchery introductions may significantly reduce the production and
survival of native, naturally-reproducing steelhead. Furthermore,
collection of native steelhead for hatchery broodstock purposes may
result in additional negative impacts to small or dwindling natural
populations. It is important to note, however, that artificial
propagation could play an important role in steelhead recovery and that
some hatchery populations of steelhead may be deemed essential for the
recovery of threatened or endangered steelhead ESUs (see Proposed
Determination). In addition, alternative uses of supplementation, such
as for the creation of terminal fisheries, must be fully explored to
try to limit negative impacts to remaining natural populations. This
use must be tempered with the understanding that protecting native,
naturally-reproducing steelhead and their habitats is critical to
maintaining healthy, fully-functioning ecosystems.
Proposed Determination
The ESA defines an endangered species as any species in danger of
extinction throughout all or a significant portion of its range, and a
threatened species as any species likely to become an endangered
species within the foreseeable future throughout all or a significant
portion of its range. Section 4(b)(1) of the ESA requires that the
listing determination be 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 those efforts, if any, being
made to protect such species.
Based on results from its coastwide assessment, NMFS has determined
that on the west coast of the United States, there are fifteen ESUs of
steelhead which constitute ``species'' under the ESA. NMFS has
determined that five ESUs are currently endangered (Central California
Coast, South Central California Coast, Southern California, Central
Valley, and Upper Columbia ESUs) and another five ESUs are currently
threatened (Snake River Basin, lower Columbia River, Oregon Coast,
Klamath Mountains Province, and northern California ESUs) and NMFS
proposes to list them as such at this time. The geographic boundaries
(i.e., the watersheds within which the members of the ESU spend their
freshwater residence) for these ESUs are described under ``ESU
Determinations.''
The Klamath Mountains Province ESU was proposed for listing under a
previous determination (60 FR 14253, March 16, 1995). However, due to
unresolved issues and practical considerations, NMFS believes it more
prudent to make a final determination on Klamath Mountains Province
steelhead in the context of final determinations for West Coast
steelhead ESUs. NMFS has received comments on the previous proposal to
list this ESU and will seek additional information that should help
clarify the degree of risk faced by Klamath Mountains Province
steelhead. The agency will make a final determination on this ESU
concurrently with final listing
[[Page 41558]]
determinations on all west coast steelhead ESUs.
NMFS has determined that steelhead in the Middle Columbia River ESU
(the Columbia River Basin from Mosier Creek, OR, upstream to the Yakima
River, WA) do not warrant listing. However, because there is sufficient
concern regarding the health of steelhead in this region, NMFS is
adding this ESU to its candidate species list. NMFS will conduct a
thorough reevaluation of the status of this ESU before the final
listing determination.
In all 10 ESUs identified as threatened or endangered, only native,
naturally-reproducing steelhead are being proposed for listing. Prior
to the final listing determination, NMFS will examine the relationship
between hatchery and natural populations of steelhead in these ESUs,
and assess whether any hatchery populations are essential for their
recovery. This may result in the inclusion of specific hatchery
populations as part of a listed ESU in NMFS' final determination.
In addition, NMFS is proposing to list only anadromous life forms
of O. mykiss at this time due to uncertainties regarding the
relationship between resident rainbow trout and steelhead. Prior to the
final listing determination, NMFS will seek additional information on
this issue and work with the U.S. Fish and Wildlife Service and
fisheries comanagers to better define the relationship between resident
and anadromous O. mykiss in the ESUs proposed for listing.
Conservation Measures
Conservation measures provided to species listed as endangered or
threatened under the ESA include recognition, recovery actions, Federal
agency consultation requirements, and prohibitions on taking.
Recognition through listing promotes public awareness and conservation
actions by Federal, state, and local agencies, private organizations,
and individuals.
Several conservation efforts are underway that may reverse the
decline of west coast steelhead and other salmonids. These include the
Northwest Forest Plan (on Federal lands within the range of the
northern spotted owl), Pacfish (on all additional Federal lands with
anadromous salmonid populations), Oregon's Coastal Salmon Restoration
Initiative, Washington's Wild Stock Restoration Initiative,
California's Coastal Salmon Initiative and Steelhead Management Plan,
NMFS' Proposed Recovery Plan for Snake River Salmon, and a Draft
Recovery Plan for Sacramento Winter-run Chinook Salmon. NMFS is very
encouraged by a number of these efforts and believes that they have or
may constitute significant strides in the efforts in the region to
develop a scientifically well grounded conservation plan for these
stocks. NMFS intends to support and work closely with these efforts--
staff and resources permitting--in the belief that they could have a
substantial impact on a final decision on the need to list these stocks
or on the type of final listing. The degree to which these conservation
efforts are able to provide reliable, scientifically well grounded
commitments through a variety of measures to provide for the
conservation of these stocks will have a direct and substantial effect
on any final listing determination of NMFS.
Section 7(a)(4) of the ESA requires that Federal agencies confer
with NMFS on any actions likely to jeopardize the continued existence
of a species proposed for listing and on actions likely to result in
the destruction or adverse modification of proposed critical habitat.
For listed species, section 7(a)(2) requires Federal agencies to ensure
that activities they authorize, fund, or conduct are not likely to
jeopardize the continued existence of a listed species or to destroy or
adversely modify its critical habitat. If a Federal action may affect a
listed species or its critical habitat, the responsible Federal agency
must enter into consultation with NMFS.
Examples of Federal actions likely to affect steelhead include
authorized land management activities of the U.S. Forest Service and
U.S. Bureau of Land Management, as well as operation of hydroelectric
and storage projects of the Bureau of Reclamation and U.S. Army Corps
of Engineers (COE). Such activities include timber sales and harvest,
hydroelectric power generation, and flood control. Federal actions,
including the COE section 404 permitting activities under the Clean
Water Act, COE permitting activities under the River and Harbors Act,
Federal Energy Regulatory Commission licenses for non-Federal
development and operation of hydropower, and Federal salmon hatcheries,
may also require consultation.
Based on information presented in this proposed rule, general
conservation measures that could be implemented to help conserve the
species are listed below. This list does not constitute NMFS'
interpretation of a recovery plan under section 4(f) of the ESA.
1. Measures could be taken to promote land management practices
that protect and restore steelhead habitat. Land management practices
affecting steelhead habitat include timber harvest, road building,
agriculture, livestock grazing, and urban development.
2. Evaluation of existing harvest regulations could identify any
changes necessary to protect steelhead populations.
3. Artificial propagation programs could be required to incorporate
practices that minimize impacts upon native populations of steelhead.
4. Efforts could be made to ensure that existing and proposed dam
facilities are designed and operated in a manner that will not
adversely affect steelhead populations. For example, NMFS could require
that fish passage facilities at dams effectively pass migrating
juvenile and adult steelhead.
5. Water diversions could have adequate headgate and staff gauge
structures installed to control and monitor water usage accurately.
Water rights could be enforced to prevent irrigators from exceeding the
amount of water to which they are legally entitled.
6. Irrigation diversions affecting downstream migrating steelhead
trout could be screened. A thorough review of the impact of irrigation
diversions on steelhead could be conducted.
NMFS recognizes that, to be successful, protective regulations and
recovery programs for steelhead will need to be developed in the
context of conserving aquatic ecosystem health. NMFS intends that
Federal lands and Federal activities play a primary role in preserving
listed populations and the ecosystems upon which they depend. However,
throughout the range of all ten ESUs proposed for listing, steelhead
habitat occurs and can be affected by activities on state, tribal or
private land. Agricultural, timber, and urban management activities on
nonfederal land could and should be conducted in a manner that avoids
adverse effects to steelhead habitat.
NMFS encourages nonfederal landowners to assess the impacts of
their actions on potentially threatened or endangered salmonids. In
particular, NMFS encourages the formulation of watershed partnerships
to promote conservation in accordance with ecosystem principles. These
partnerships will be successful only if state, tribal, and local
governments, landowner representatives, and Federal and nonfederal
biologists all participate and share the goal of restoring steelhead to
the watersheds.
Section 9 of the ESA prohibits certain activities that directly or
indirectly affect endangered species. These prohibitions apply to all
individuals, organizations, and agencies subject to
[[Page 41559]]
U.S. jurisdiction. Section 4(d) of the ESA allows the promulgation of
protective regulations that modify or apply any or all of the
prohibitions of section 9 to threatened species. Section 9 prohibits
violations of protective regulations for threatened species promulgated
under section 4(d).
At this time, NMFS proposes to adopt protective measures to
prohibit ``taking,'' interstate commerce, and the other ESA
prohibitions applicable to endangered species, with the exceptions
provided under section 10 of the ESA, for the five ESUs of steelhead
proposed as threatened herein. Under the ESA, the term ``take'' means
to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or
collect, or to attempt to engage in any such conduct. NMFS is proposing
to extend the provisions of section 9 and section 10 to these ESUs to
provide immediate protections to them upon final listing. However,
prior to the final listing determination, NMFS will consider adopting
specific regulations under section 4(d) that will apply to one or more
ESUs of steelhead identified as threatened (see Public Comments
Solicited). These regulations, promulgated pursuant to the
Administrative Procedures Act, 5 U.S.C. 551 et seq., may be in lieu of
the Section 9 taking prohibition and Section 10 permit exception.
Sections 10(a)(1)(A) and 10(a)(1)(B) of the ESA provide NMFS with
authority to grant exceptions to the ESA's ``taking'' prohibitions.
Section 10(a)(1)(A) scientific research and enhancement permits may be
issued to entities (Federal and non-Federal) conducting research that
involves a directed take of listed species. A directed take refers to
the intentional take of listed species. NMFS has issued section
10(a)(1)(A) research/enhancement permits for other listed species
(e.g., Snake River chinook salmon and Sacramento River winter-run
chinook salmon) for a number of activities, including trapping and
tagging, electroshocking to determine population presence and
abundance, removal of fish from irrigation ditches, and collection of
adult fish for artificial propagation programs.
Section 10(a)(1)(B) incidental take permits may be issued to non-
Federal entities performing activities which may incidentally take
listed species. The types of activities potentially requiring a section
10(a)(1)(B) incidental take permit include the operation and release of
artificially propagated fish by state or privately operated and funded
hatcheries, state or University research not receiving Federal
authorization or funding, and the implementation of state fishing
regulations. NMFS Policies on Endangered and Threatened Fish and
Wildlife
On July 1, 1994, NMFS, jointly with the U.S. Fish and Wildlife
Service, published a series of policies regarding listings under the
ESA, including a policy for peer review of scientific data (59 FR
34270) and a policy to identify, to the maximum extent possible, those
activities that would or would not constitute a violation of section 9
of the ESA (59 FR 34272).
Role of peer review: The intent of the peer review policy is to
ensure that listings are based on the best scientific and commercial
data available. Prior to a final listing, NMFS will solicit the expert
opinions of three qualified specialists, concurrent with the public
comment period. Independent peer reviewers will be selected from the
academic and scientific community, Tribal and other native American
groups, Federal and state agencies, and the private sector.
Identification of those activities that would constitute a
violation of Section 9 of the ESA: The intent of this policy is to
increase public awareness of the effect of this listing on proposed and
ongoing activities within the species' range. NMFS will identify, to
the extent known at the time of the final rule, specific activities
that will not be considered likely to result in violation of section 9,
as well as activities that will be considered likely to result in
violation. NMFS believes that, based on the best available information,
the following actions will not result in a violation of section 9:
(1) Possession of steelhead acquired lawfully by permit issued by
NMFS pursuant to section 10 of the ESA, or by the terms of an
incidental take statement pursuant to section 7 of the ESA.
(2) Federally approved projects that involve activities such as
silviculture, grazing, mining, road construction, dam construction and
operation, discharge of fill material, stream channelization or
diversion for which consultation has been completed, and when such
activity is conducted in accordance with any terms and conditions given
by NMFS in an incidental take statement accompanied by a biological
opinion.
Activities that NMFS believes could potentially harm the steelhead
and result in ``take'', include, but are not limited to:
(1) Unauthorized collecting or handling of the species. Permits to
conduct these activities are available for purposes of scientific
research or to enhance the propagation or survival of the species.
(2) Unauthorized destruction/alteration of the species' habitat
such as removal of large woody debris or riparian shade canopy,
dredging, discharge of fill material, draining, ditching, diverting,
blocking, or altering stream channels or surface or ground water flow.
(3) Discharges or dumping of toxic chemicals or other pollutants
(i.e., sewage, oil and gasoline) into waters or riparian areas
supporting the species.
(4) Violation of discharge permits.
(5) Pesticide applications in violation of label restrictions.
(6) Interstate and foreign commerce (commerce across State lines
and international boundaries) and import/export without prior
obtainment of an endangered species permit.
This list is not exhaustive. It is provided to give the reader some
examples of the types of activities that may be considered by the NMFS
as constituting a ``take'' of steelhead under the ESA and regulations.
Questions regarding whether specific activities will constitute a
violation of section 9, and general inquiries regarding prohibitions
and permits, should be directed to NMFS (see ADDRESSES).
Critical Habitat
Section 4(a)(3)(A) of the ESA requires that, to the extent prudent
and determinable, critical habitat be designated concurrently with the
listing of a species. While NMFS has completed its initial analysis of
the biological status of steelhead populations from Washington, Oregon,
Idaho, and California, it has not performed the analysis (including
economic analysis) necessary for designating critical habitat. Further,
NMFS is placing a higher priority on listings than on critical habitat
designations due to staffing and workload constraints resulting from
the lifting of the recent listing moratorium. In most cases, the
substantive protections of critical habitat designations are
duplicative of those of listings, however, in cases in which critical
habitat designation is deemed essential to the conservation of the
species, such a designation could warrant a higher priority. It is
NMFS' intention to develop and publish a critical habitat designation
for West Coast steelhead as time and workload permit.
Public Comments Solicited
To ensure that the final action resulting from this proposal will
be as accurate and effective as possible, NMFS is soliciting comments
and suggestions from the public, other
[[Page 41560]]
governmental agencies, the scientific community, industry, and any
other interested parties. Public hearings will be held in several
locations in the range of the proposed ESUs; details regarding
locations, dates, and times will be published in a forthcoming Federal
Register notice. NMFS recognizes that there are serious limits to the
quality of information available, and, therefore, NMFS has executed its
best professional judgment in developing this proposal. NMFS will
appreciate any additional information regarding, in particular: (1) The
relationship between rainbow trout and steelhead, specifically whether
rainbow trout and steelhead populations in the same geographic area
should be considered a single ESU; (2) biological or other relevant
data concerning any threat to steelhead or rainbow trout; (3) the
range, distribution, and population size of steelhead and rainbow trout
in all identified ESUs; (4) current or planned activities in the
subject areas and their possible impact on this species; (5) steelhead
escapement, particularly escapement data partitioned into natural and
hatchery components; (6) the proportion of naturally-reproducing fish
that were reared as juveniles in a hatchery; (7) homing and straying of
natural and hatchery fish; (8) the reproductive success of naturally-
reproducing hatchery fish (i.e., hatchery-produced fish that spawn in
natural habitat) and their relationship to the identified ESUs; (9)
efforts being made to protect native, naturally-reproducing populations
of steelhead and rainbow trout in Washington, Oregon, Idaho and
California; and (10) suggestions for specific regulations under section
4(d) of the ESA that should apply to threatened steelhead ESUs.
Suggested regulations may address activities, plans, or guidelines
that, despite their potential to result in the incidental take of
listed fish, will ultimately promote the conservation and recovery of
threatened steelhead.
NMFS is also requesting quantitative evaluations describing the
quality and extent of freshwater and marine habitats for juvenile and
adult steelhead as well as information on areas that may qualify as
critical habitat in Washington, Oregon, Idaho, and California for the
proposed ESUs. Areas that include the physical and biological features
essential to the recovery of the species should be identified. NMFS
recognizes that there are areas within the proposed boundaries of some
ESUs that historically constituted steelhead habitat, but may not be
currently occupied by steelhead. NMFS is requesting information about
steelhead in these currently unoccupied areas (in particular, for the
Southern California and Central Valley ESUs) and whether these habitats
should be considered essential to the recovery of the species or
excluded from designation. Essential features include, but are not
limited to: (1) Habitat for individual and population growth, and for
normal behavior; (2) food, water, air, light, minerals, or other
nutritional or physiological requirements; (3) cover or shelter; (4)
sites for reproduction and rearing of offspring; and (5) habitats that
are protected from disturbance or are representative of the historic
geographical and ecological distributions of the species.
For areas potentially qualifying as critical habitat, NMFS is
requesting information describing: (1) The activities that affect the
area or could be affected by the designation, and (2) the economic
costs and benefits of additional requirements of management measures
likely to result from the designation.
The economic cost to be considered in the critical habitat
designation under the ESA is the probable economic impact ``of the
[critical habitat] designation upon proposed or ongoing activities''
(50 CFR 424.19). NMFS must consider the incremental costs specifically
resulting from a critical habitat designation that are above the
economic effects attributable to listing the species. Economic effects
attributable to listing include actions resulting from section 7
consultations under the ESA to avoid jeopardy to the species and from
the taking prohibitions under section 9 of the ESA. Comments concerning
economic impacts should distinguish the costs of listing from the
incremental costs that can be directly attributed to the designation of
specific areas as critical habitat.
NMFS will review all public comments and any additional information
regarding the status of the steelhead ESUs described herein and, as
required under the ESA, will complete a final rule within 1 year of
this proposed rule. The availability of new information may cause NMFS
to reassess the status of steelhead ESUs. In particular, NMFS will
conduct a thorough reevaluation of the status of the Middle Columbia
River ESU before the final listing determination. Although NMFS has
concluded that information available at the present time is not
sufficient to demonstrate that a listing is warranted for this ESU,
there is concern over the health of natural populations in this ESU.
NMFS is aware and strongly supportive of the current efforts by the
states of Oregon, Washington, and California to develop effective and
scientifically based conservation measures to address at-risk salmon
and steelhead stocks. NMFS believes that these efforts, if successful,
could serve as the central components of a broad conservation program
that would provide a steady, predictable, and well grounded road to
recovery and rebuilding of these stocks. NMFS intends to work closely
with these efforts and those of local or regional watershed groups, as
well as other involved Federal agencies, and hopes that this proposal
will add greater impetus to those efforts.
References
A complete list of all references cited herein is available upon
request (see ADDRESSES section).
Classification
The 1982 amendments to the ESA, in section 4(b)(1)(A), restrict the
information that may be considered when assessing species for listing.
Based on this limitation of criteria for a listing decision and the
opinion in Pacific Legal Foundation v. Andrus, 675 F. 2d 825 (6th Cir.
1981), NMFS has categorically excluded all ESA listing actions from
environmental assessment requirements of the National Environmental
Policy Act under NOAA Administrative Order 216-6.
This proposed rule is exempt from review under E.O. 12866.
Dated: July 31, 1996.
C. Karnella,
Acting Program Management Officer, National Marine Fisheries Service.
List of Subjects
50 CFR Part 222
Administrative practice and procedure, Endangered and threatened
wildlife, Exports, Imports, Reporting and recordkeeping requirements,
Transportation.
50 CFR Part 227
Endangered and threatened species, Exports, Imports, Marine
mammals, Transportation.
For the reasons set out in the preamble, 50 CFR parts 222 and 227
are proposed to be amended as follows:
PART 222--ENDANGERED FISH OR WILDLIFE
1. The authority citation of Part 222 continues to read as follows:
Authority: 16 U.S.C. 1531 et seq.
[[Page 41561]]
Sec. 222.23 [Amended]
2. In Sec. 222.23, paragraph (a) is amended by adding the phrases
``Central California Coast steelhead (Oncorhynchus mykiss); South-
Central California Coast steelhead (Oncorhynchus mykiss); Southern
California steelhead (Oncorhynchus mykiss); Central Valley steelhead
(Oncorhynchus mykiss); and Upper Columbia River steelhead (Oncorhynchus
mykiss);'' immediately after the phrase ``Umpqua River cutthroat trout
(Oncorhynchus clarki clarki)''.
PART 227--THREATENED FISH AND WILDLIFE
1. The authority citation for part 227 continues to read as
follows:
Authority: 16 U.S.C. 1531 et seq.
2. In Sec. 227.4, paragraphs (n), (o), (p), and (q) are added to
read as follows:
Sec. 227.4 Enumeration of threatened species.
* * * * *
(n) Lower Columbia River steelhead (Oncorhynchus mykiss)
(o) Oregon Coast steelhead (Oncorhynchus mykiss)
(p) Northern California steelhead (Oncorhynchus mykiss)
(q) Snake River Basin steelhead (Oncorhynchus mykiss).
3. Section 227.21 is revised to read as follows:
Sec. 227.21 Threatened salmon.
(a) Prohibitions. The prohibitions of section 9 of the Act (16
U.S.C. 1538) relating to endangered species apply to threatened species
of salmon listed in Sec. 227.4 (f), (g), (j), (k), (l), (m), (n), (o),
(p), and (q) except as provided in paragraph (b) of this section.
(b) Exceptions. The exceptions of section 10 of the Act (16 U.S.C.
1539) and other exceptions under the Act relating to endangered
species, including regulations implementing such exceptions, also apply
to the threatened species of salmon listed in Sec. 227.4 (f), (g), (j),
(k), (l), (m), (n), (o), (p), and (q). This section supersedes other
restrictions on the applicability of parts 217 and 222 of this chapter,
including, but not limited to, the restrictions specified in
Secs. 217.2 and 222.22(a) of this chapter with respect to the species
identified in Sec. 227.21(a).
[FR Doc. 96-20030 Filed 8-8-96; 8:45 am]
BILLING CODE 3510-22-P