BPA Fish and Wildlife FY 1997 Proposal

Section 1. Administrative
Section 2. Narrative
Section 3. Budget

see CBFWA and BPA funding recommendations

Section 1. Administrative

Title of project
Redfish Lake Sockeye Salmon Captive Broodstock Rearing and Research

BPA project number   9204000

Business name of agency, institution or organization requesting funding
NMFS

Sponsor type   WA-Federal Agency

Proposal contact person or principal investigator

BPA technical contact   Jeff Gislason, EWN 503/230-3594

Biological opinion ID   NMFS

NWPPC Program number   7.5A.1

Short description
Incubate and rear juvenile Redfish Lake sockeye salmon; compare freshwater and saltwater rearing for sockeye salmon.

Project start year   1992    End year   

Start of operation and/or maintenance   

Project development phase   Implementation

Section 2. Narrative

Related projects
BPA Project 91-72: Idaho Department of Fish and Game is also maintaining captive broodstocks for Snake River sockeye salmon to avoid catastrophic loss of the gene pool and for rebuilding efforts; BPA Project 91-71: The Shoshone-Bannock Tribe of Idaho are conducting habitat and limnological research for rebuilding efforts for Snake River sockeye salmon; BPA Project 90-093: The University of Idaho and Washington State University have been conducting genetic analyses of Snake River sockeye salmon.

Project history
The Coastal Zone and Estuarine Studies Division, National Marine Fisheries Service (NMFS), in collaboration with the Idaho Department of Fish and Game and the Shoshone-Bannock Tribes, has been conducting research to prevent extinction of Snake River sockeye salmon. NMFS listed the Snake River sockeye salmon as endangered under the U.S. Endangered Species Act (ESA) in December 1991. NMFS recovery efforts for this stock center on captive broodstocks for production of juveniles for supplementation. Implementation and refinement of captive broodstocks for recovery of Snake River sockeye salmon are identified as a priorities [4.1.a; 4.1.cl in the proposed Recovery Plan for Snake River salmon.
Snake River sockeye salmon are a prime example of a species on the threshold of extinction. The last known remnants of this stock return to Redfish Lake in the Sawtooth Basin of Idaho at the headwaters of the Salmon River. Only a few sockeye salmon adults (one to eight per year) have returned to Redfish Lake in each of the last 5 years. on the basis of these critically low population numbers, NMFS implemented captive broodstocks as an emergency measure for Redfish Lake sockeye salmon.
Redfish Lake sockeye salmon captive broodstocks are being maintained in captivity throughout their life and their offspring will be released to supplement the wild population. Each yearclass is maintained for only a single generation, or a limited number of generations, to help assure that adaptability to native habitats is preserved. Mating strategies for fish reared in captivity have been established to maintain and enhance genetic diversity.
Theoretically, the relatively high fecundity of anadromous Pacific salmon, coupled with potentially high survival in protective culture, should allow captive broodstocks to produce large numbers of juveniles in a single generation to help "jumpstart" the population. Nevertheless, although the basis for captive broodstock technology is known, its application to threatened and endangered stocks of Pacific salmon is in its infancy. Therefore, research to refine aspects of captive broodstocking has been conducted using surrogate sockeye salmon stocks (e.g., Lake Wenatchee).
Supplementation with juveniles from captive broodstocks will result in substantial returns of adults sockeye salmon to Redfish Lake and should lead to rebuilding of the natural run and delisting.

Biological results achieved
NMFS has almost 2,100 endangered Redfish Lake sockeye salmon from fish that returned to the lake in 1991-1995 in protective culture. The first group of captive-reared fish (1991 brood) spawned in fall 1994; producing almost 50,000 viable eggs. NMFS captive broodstocks are projected to produce over 500,000 eggs between 1995-1998. Eggs from these spawnings will be returned to Idaho to aid recovery efforts for Snake River sockeye salmon.
Research with Lake Wenatchee sockeye salmon has demonstrated feasibility of captive broodstock culture in seawater net-pens, and rearing vessels supplied with either filtered and UV sterilized or pathogen-free freshwater. Initial results suggest that captive broodstock culture in pathogen-free (fresh or sea) water has a higher likelihood of ensuring survival of sockeye salmon than culture in seawater net-pens. Initial research indicates that rearing fish full-term to maturity in freshwater does not compromise seawater adaptability of offspring.

Annual reports and technical papers
Flagg, T. A., C. V. W. Mahnken, and K. A. Johnson. 1995. Captive broodstocks for recovery of depleted populations of Pacific salmon. Amer. Fish. Soc. Symp. 15:81-90.

Flagg, T. A., K. A. Johnson, and J. C. Gislason. 1994. Redfish Lake sockeye salmon broodstock programs. In Proceedings of the 1993 Alaska Department of Fish and Game Sockeye Culture Workshop. Cooper Landing, Alaska. 10 p. (Available from Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA 98112.)

Flagg, T. A. 1993. Redfish Lake sockeye salmon captive broodstock rearing and research, 1991-1992. Report to Bonneville Power Administration, Contract DE-AI79-92BP41841. 16 p. (Available from Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA 98112.)

Flagg, T. A., and W. C. McAuley. 1994. Redfish Lake sockeye salmon captive broodstock rearing and research, 1991-1993. Report to Bonneville Power Administration, Contract DE-AI79-92BP41841. 99 p. (Available from Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA 98112.)

Flagg, T. A., W. C. McAuley, M. R. Wastel, D. A. Frost, and C. V. W. Mahnken. In prep. Redfish Lake sockeye salmon captive broodstock rearing and research, 1991-1994. Report to Bonneville Power Administration, Contract DE-AI79-92BP41841. (Available from Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA 98112.)

Management implications
Because of the critically low population size of Redfish Lake sockeye salmon, captive broodstocks appear to offer the only hope to maintain the species while habitat improvements are underway. Maintaining geographically separate captive brood populations will help reduce the risk of catastrophic loss of the Redfish Lake sockeye salmon gene pool from mechanical failure, human error, or disease. In upcoming years, the Redfish Lake captive broodstock programs should provide hundreds of thousands of eggs for use in recovery efforts. It is virtually certain that without the boost provided by these captive broodstock projects, Redfish Lake sockeye salmon would soon be extinct.

Specific measureable objectives
Rear endangered groups of Redfish Lake sockeye salmon captive broodstocks to maturity and spawn fish. Incubate eggs and make eggs available to Idaho for use in recovery efforts for this endangered species.

Testable hypothesis
1. Endangered Redfish Lake sockeye salmon grown to maturity in freshwater have similar growth, survival, and reproductive success as fish grown in seawater.

2. Endangered Redfish Lake sockeye salmon captive broodstocks will produce gametes in sufficient numbers and of sufficient quality to aid recovery efforts.

Underlying assumptions or critical constraints
Habitat improvements in the nursery lake and in the migration corridor will occur to allow natural long-term increases in population replacement rate.

Methods
1. Replicated groups of endangered Redfish Lake sockeye salmon will be reared to maturity in 4.1-m circular fiberglass tanks supplied with either fresh well water or filtered and sterilized seawater. At maturity, fish will be spawned and individual families incubated in isolation..

2. Appropriate statistical analysis will be conducted to compare growth, survival, and reproductive success of fish grown in freshwater and seawater.

3. Between 400 - 1,000 fish of each brood year and brood type of Redfish Lake sockeye salmon are being reared in protective culture.

Brief schedule of activities
FY1997: Participate in recovery efforts for Snake River sockeye salmon. Rear 1993-, 1994- and 1995-broods of Redfish Lake sockeye salmon as captive broodstock, including:

1. Fall 1996 - spawn 1993-brood(s) of Redfish Lake sockeye salmon maturing as 3-year-old fish from both freshwater and seawater. Compare reproductive success.

2. Fall 1996-winter 1977 - incubate eggs spawned from captive broodstocks and make eggs available to Idaho for recovery efforts at Redfish Lake.

3. Begin captive broodstock sourced from sockeye salmon captured returning to Redfish Lake Idaho.

4. Begin second generation “safety-net” captive broodstock from 1996 spawning of captive broodstocks.

5. Write reports and scientific papers.

Similar project activities are expected in 1998-2001.

Biological need
Both first and “safety-net” second generation captive broodstocks are identified as priorities [4.1.a] to aid recovery in the Proposed Recovery Plan for Snake River Salmon. Because of the critically low population size of Redfish Lake sockeye salmon, captive broodstocks appear to offer the only hope to maintain the species while habitat improvements are underway. Maintaining geographically separate captive brood populations will help reduce the risk of catastrophic loss of the Redfish Lake sockeye salmon gene pool from mechanical failure, human error, or disease. In upcoming years, the Redfish Lake captive broodstock programs should provide hundreds of thousands of eggs for use in recovery efforts. It is virtually certain that without the boost provided by these captive broodstock projects, Redfish Lake sockeye salmon would soon be extinct.

Critical uncertainties
Whether endangered Redfish Lake sockeye salmon captive broodstocks will produce gametes in sufficient numbers and of sufficient quality to aid recovery efforts.

Summary of expected outcome
Maintaining geographically separate captive brood populations will help reduce the risk of catastrophic loss of the Redfish Lake sockeye salmon gene pool. In upcoming years, the Redfish Lake captive broodstock programs should provide hundreds of thousands of eggs for use in recovery efforts.

Dependencies/opportunities for cooperation
NMFS is cooperating with the Idaho Department of Fish and Game in using captive broodstocks to aid rebuilding of Snake River sockeye salmon. Cooperative efforts for restoration of Snake River sockeye salmon are being coordinated through the Stanley Basin Technical Oversight Committee.

Risks
No known critical risks are associated with captive broodstock rearing for Redfish Lake sockeye salmon. In fact, as described above, it is virtually certain that without the boost provided by these captive broodstock projects, Redfish Lake sockeye salmon would soon be extinct.

Monitoring activity
Reproductive success of captive broodstocks will be monitored for each brood year. Cooperative studies directed through the Stanley Basin Technical Oversight Committee will juvenile outmigration and adult returns from progeny of captive broodstock released in Redfish Lake.

Section 3. Budget

* For most projects, Authorized is the amount recommended by CBFWA and the Council. Planned is amount currently allocated. Contracted is the amount obligated to date of printout.

Funding recommendations

CBFWA funding review group   Snake River

Recommendation    Tier 1 - fund

Recommended funding level   $500,000

BPA 1997 authorized budget (approved start-of-year budget)   $500,000