[Federal Register Volume 59, Number 4 (Thursday, January 6, 1994)]
[Proposed Rules]
[Pages 869-871]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-92]
[[Page Unknown]]
[Federal Register: January 6, 1994]
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DEPARTMENT OF THE INTERIOR
50 CFR Part 17
Endangered and Threatened Wildlife and Plants; Notice of 1-Year
Finding on a Petition to List the Longfin Smelt
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Notice of petition finding.
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SUMMARY: The U.S. Fish and Wildlife Service (Service) announces a 1-
year finding on a petition to list the longfin smelt (Spirinchus
thaleichthys) under the Endangered Species Act of 1973, as amended
(Act). The Service determines that the petitioned action is not
warranted at this time. The longfin smelt occurs from the San Francisco
Bay-Sacramento-San Joaquin River Estuary in California to Prince
William Sound in Alaska. Although the southernmost populations are
declining, little or no population trend data are available for
estuaries in Oregon and Washington. The species may be surviving and
reproducing in Puget Sound, Skagit Bay, Grays Harbor, Willapa Bay, the
Columbia River, Yaquina Bay, and Coos Bay. Large numbers are found in
the Gulf of Alaska 5 to 6 miles off shore. The listing of a Sacramento-
San Joaquin River estuary vertebrate population segment is also not
warranted at this time because that population does not seem to be
biologically significant to the species as a whole, and may not be
sufficiently reproductively isolated.
DATES: Comments from all interested parties will be accepted until
further notice.
ADDRESSES: Comments and materials concerning this document should be
submitted to the Acting Field Supervisor, Sacramento Field Office, U.S.
Fish and Wildlife Service, 2800 Cottage Way, E-1803, Sacramento,
California 95825-1846.
FOR FURTHER INFORMATION CONTACT: H. Dale Hall, Assistant Regional
Director, Ecological Services, U.S. Fish and Wildlife Service, 911 NE.
11th Avenue, Portland, Oregon 97232-4181 (503/231-6150).
SUPPLEMENTARY INFORMATION: On November 5, 1992, the Service received a
petition from Mr. Gregory A. Thomas of the Natural Heritage Institute
to add the longfin smelt to the List of Endangered and Threatened
Wildlife and to designate critical habitat in the Sacramento and San
Joaquin Rivers and estuary. In his letter, Mr. Thomas identified the
following eight organizations as co-petitioners: American Fisheries
Society, Bay Institute of San Francisco, Natural Heritage Institute,
Planning and Conservation League, Save San Francisco Bay Association,
Friends of the River, San Francisco Baykeeper, and the Sierra Club. On
June 24, 1993, the Service issued a 90-day finding, a notice of which
was published in the Federal Register on July 6, 1993 (58 FR 36184),
that the petition presented substantial information indicating that the
requested action may be warranted. The Service initiated a status
review and analyzed available data on this species (Meng 1993).
Additional sources of information describing the human factors and
projects that may affect this species include expert testimonies
presented to the California State Water Resources Control Board's 1987
Water Quality/Water Rights Proceeding on the San Francisco Bay and
Sacramento-San Joaquin River Delta and 1992 Water Rights Phase of the
Bay-Delta Estuary Proceedings.
Section 4(b)(3)(B) of the Act requires that the Service issue a
finding within 1 year of the receipt of the petition on whether the
petitioned action is (a) not warranted, (b) warranted, or (c) warranted
but precluded from immediate proposal by other pending proposals of
higher priority.
In casual conversations, the petitioner indicated that he intended
the petition to be a request to list the Sacramento-San Joaquin River
estuary population. However, the Service did not receive this request
in writing and, in any case, was required to review the status of the
species on a rangewide basis prior to considering the appropriateness
of listing individual population segments. The Service determines that
listing of the Sacramento-San Joaquin estuary population segment of the
longfin smelt is not warranted.
Longfin smelt is an euryhaline species with a 2-year life cycle
(Moyle 1976, Moyle and Yoshiyama 1992). Spawning occurs in fresh water
over sandy-gravel substrates, rocks, or aquatic plants. Spawning may
take place as early as November and extend into June, although the peak
spawning period is from February to April (Wang 1986). After hatching,
larvae move up into surface waters and are transported downstream into
brackish-water nursery areas. Sacramento-San Joaquin River outflow into
Suisun and San Pablo Bays has been positively correlated with longfin
smelt recruitment (Stevens and Miller 1983) because higher outflow
increases larval dispersal and the area available for rearing (Wang
1986). The main food of longfin smelt is opossum shrimp, although
copepods and other crustaceans also are eaten (Moyle 1976). Longfin
smelt are preyed upon by fishes, birds, and marine mammals (Monaco et
al. 1991). Longfin smelt play a role in maintaining the structure and
function of estuarine ecosystems because they are important as food for
birds and piscivorous fishes.
As presently described, longfin smelt range from the San Joaquin-
Sacramento River estuary and South San Francisco Bay, California, to
Prince William Sound, Alaska (Miller and Lea 1972). The present-day
distribution of longfin smelt is probably due to lower sea levels in
the Pleistocene, which would have enlarged estuaries up and down the
Pacific coast and shortened the distances between estuaries, as well as
provide more habitat (Peter Moyle, University of California, Davis,
pers. comm., 1993). Unverified reports of off-shore collection of
longfin smelt exist, approximately 5 to 6 miles off shore in Alaska
(Bruce Wing, National Marine Fisheries Service, Auke Bay, Alaska, pers.
comm., 1993) and 3 to 4 miles off shore in northern California (Larry
Quirollo, California Department of Fish and Game, pers. comm., 1993).
Based on inferred abundance, longfin smelt may be common in Willapa
Bay, Skagit Bay, and Puget Sound in Washington and Coos Bay and Yaquina
Bay in Oregon (Monaco et al. 1990). Largely using sampling data, Monaco
et al. (1990) also reported that longfin smelt were common to highly
abundant in the Columbia River and Grays Harbor, Washington. Few data
exist on the recent status of the Oregon and Washington longfin smelt;
however, indications are that this species may be reproducing and
surviving in the Oregon and Washington estuaries (Bob Emmett, National
Marine Fisheries Service, Hammond, Oregon, pers. comm., 1993). A land-
locked population exists in Harrison Lake in British Columbia. British
Columbia longfin smelt have also been recorded at the Fraser River
estuary and near Prince Rupert and Vancouver (Hart 1973). Alaska
longfin smelt are found at the Dixon Entrance, Yakutat Bay, Prince
William Sound, and Cook Inlet (Wing, pers. comm., 1993). In California,
the longfin smelt occurs (or did occur) in the Klamath River mouth,
Humboldt Bay, Eel River mouth, Van Duzen River mouth, and the San
Francisco Bay-Sacramento-San Joaquin Estuary (Moyle 1976; Moyle and
Yoshiyama 1992; Ron Fritzsche, Humboldt State University, pers. comm.,
1993). The Estuary supports the largest and most southerly longfin
smelt population in California (Lee et al. 1980).
The strongest information on the decline of longfin smelt comes
from the Sacramento-San Joaquin River Estuary of California. Longfin
smelt were once one of the most abundant fish caught by trawl surveys
in the Sacramento-San Joaquin (Herbold et al. 1992) and Humboldt Bay
estuaries (Barnhart, pers. comm., 1993). Longfin smelt numbers in the
Estuary fluctuated widely in the past, but since 1983 abundance has
dropped dramatically and remained at record lows. In Humboldt Bay,
longfin smelt were the fourth most abundant fish captured in trawls in
the late 1960s and early 1970s (Roger Barnhart, National Biological
Survey, pers. comm., 1993). However, since 1988, no longfin smelt have
been captured in Humboldt Bay using similar sampling methods (Tim
Mulligan, Humboldt State University, pers. comm., 1993). Historical
records of longfin smelt from the mouth of the Van Duzen River exist;
however, in recent years, no evidence of the fish exists for this
location (Fritzsche, pers. comm., 1993). The Eel River, which is about
3.2 kilometers (2 miles) from Humboldt Bay, is relatively small and
probably contains little habitat appropriate for longfin smelt. Longfin
smelt likely occurred in the Eel River only when high river outflows
introduced fish from Humboldt Bay. Longfin smelt numbers probably
declined in the Eel River at the same time declines occurred in
Humboldt Bay. Recent surveys have not found the longfin in the Eel
estuary (Moyle, pers. comm., 1993). In Oregon and Washington, no
population trend data exist for any of the estuaries, although the
indications are that the species is surviving and reproducing in
several estuaries (Emmett, pers. comm., 1993). In Alaska, large numbers
of longfin smelt are found in the Gulf of Alaska (Bruce Wing, National
Marine Fisheries Service, pers. comm., 1993).
In the Sacramento-San Joaquin River Estuary the decline in longfin
smelt abundance is associated with fresh water diversions from the
Delta to support California's agricultural industry in the Central
Valley and the vast urban areas of southern California. Strong
relationships between outflow and longfin smelt abundance indicate that
outflows less than 3,400 cubic feet per second (cfs) result in
reproductive failure for longfin smelt (Moyle and Yoshiyama 1992).
Because of its 2-year life span, such flows for more than 2 or 3
consecutive years could push this species toward extinction. From 1986
to 1991, outflows hovered close to that number, partly due to high
proportions of inflow diverted. Movement of the entrapment zone (mixing
zone at the freshwater-saltwater interface) up-river due to low
outflows has constricted the range of the longfin smelt and made it
increasingly vulnerable to diversion into man-made structures. Low
outflows have failed to disperse larvae downstream to the productive
nursery areas in Suisun Bay away from the pumps. The water exports from
the Delta by far exceed those from any other estuary on the west coast
of North America.
Sediment production as a result of human activities and
developments in the Humboldt, Eel, Van Duzen, and Klamath watersheds
may be a cause of the decline of longfin smelt in those estuaries. Soil
washed into the streams can deposit in estuaries downstream.
Sedimentation in the spawning habitat could have reduced the spawning
success of this species due to physical scouring or suffocation of eggs
(Barnhart, pers. comm., 1993). Although human activities upstream of
estuaries in Oregon, Washington, Canada, and Alaska would likely result
in similar impacts, the Service does not have population trend data for
these portions of the species' range.
Longfin smelt disappeared from the Humboldt Bay estuary in the
1980s (Barnhart, pers. comm., 1993), perhaps as a result of a dramatic
loss of intertidal marsh habitat, which may have reduced productivity
levels to a point at which they could no longer support the species. In
addition, the loss of freshwater flows from the Mad River, as a result
of water diversions and land reclamation, may have contributed to the
loss of this species from the Humboldt Bay.
Longfin smelt may be particularly sensitive to adverse habitat
alterations or to stochastic events because their 2-year life cycle
increases the likelihood of extinction after consecutive periods of
reproductive failure due to drought or other factors. Relatively brief
periods of reproductive failure could lead to extirpations.
The Service has carefully assessed the best scientific and
commercial information available regarding the past, present, and
future threats faced by this species in this determination. This
species does not appear to be threatened throughout all or a
significant portion of its range or likely to become so in the
foreseeable future. However, given the declines in the southern portion
of the species' range and the general lack of population trend data for
the remainder of its range, the Service will include the longfin smelt
in category 2 of the next notice of review for animals.
Though the petition was not limited to a portion of the species'
range, the petitioner focused on the resident longfin smelt in the
Sacramento-San Joaquin River estuary population. In telephone
conversations, the petitioner indicated that he was most interested in
a population listing. Longfin smelt numbers in this estuary have
declined by 90 percent since 1984 and by 50 percent annually since
1987.
The Service has listed vertebrate population segments where the
entity being listed represented the entire coterminous United States
population (e.g., marbled murrelet, grizzly bear). Some reproductively
isolated (or nearly so) vertebrate population segments that are clearly
important to the conservation of an entire species have also been
listed under the Act (e.g., Mojave population of the desert tortoise,
coastal population of the western snowy plover).
Although the longfin smelt reportedly is unable to swim between
estuaries (Moyle, pers. comm., 1993), unverified reports of offshore
collections exist (Quirollo, pers. comm., 1993; Wing, pers. comm.,
1993). Furthermore, the current distribution is thought to be the
result of movements between estuaries that took place during the
Pleistocene when lower sea levels reportedly would have enlarged
estuaries along the Pacific coast and shortened the inter-estuarian
distances (Moyle, pers. comm., 1993). Though geographically removed
from the closest known extirpated or declining population (300 miles
from the Eel River in California), this isolation does not necessarily
indicate that the Sacramento-San Joaquin River estuary population is
significant to a species that has a range of more than 1,900 miles. In
addition, electrophoretic analysis revealed that the accumulated number
of codon substitutions per locus (i.e., Nei's genetic distance) since
the time of separation of the Sacramento-San Joaquin River estuary
population and the longfin population in Lake Washington, Washington,
connected to Puget Sound via a system of locks, has been small (0.005
according to Stanley et al., submitted to Copeia). Thus, these
populations, separated by approximately 1,000 miles, have genetically
diverged only slightly since their separation.
The Sacramento-San Joaquin River estuary is clearly an important
and significant wetland ecosystem. The longfin smelt formerly was the
fourth most abundant fish in the Sacramento-San Joaquin River estuary;
however, the role of this declining species in the estuary today is
unknown.
Based on this evaluation the Service has determined that the
listing of the longfin smelt under the Act is not warranted at this
time. The listing of the Sacramento-San Joaquin River estuary
population of the longfin smelt is also not warranted at this time.
References
A complete list of references used in the preparation of this
finding is available from the Associate Manager--Endangered Species,
U.S. Fish and Wildlife Service, Portland, Oregon (see ADDRESSES
section).
Authority
The authority for this action is the Endangered Species Act (16
U.S.C. 1531 et seq.).
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, and Transportation.
Dated: December 22, 1993.
Richard N. Smith,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 94-92 Filed 1-5-94; 8:45 am]
BILLING CODE 4310-55-P
