Project GOAL

The marine captive broodstock project's primary goal is to provide a safety net population that can be used to sustain ESA-listed stocks of spring/summer chinook salmon (Oncorhynchus tshawytscha) in years when no fish return from the sea.  In addition, the program has the goal of generating fish that can be used to aid the rebuilding of ESA-listed populations in the Snake River Basin.

BACKGROUND

In spring 1995, the Idaho Department of Fish and Game (IDFG) and the Oregon Department of Fish and Wildlife (ODFW) initiated captive broodstocks as part of conservation efforts for ESA-listed stocks of Snake River spring/summer chinook salmon.  Oregon's Snake River spring/summer chinook salmon captive broodstock program currently focuses on three stocks captured as juveniles from the Grande Ronde River Basin.  Idaho's Snake River program includes two stocks captured as eyed eggs from the Salmon River Basin.  IDFG and ODFW requested that a portion of each group be reared by NMFS in protective culture in seawater.  In August 1996, NMFS began a Bonneville Power Administration (BPA) funded project (Project 199606700) to rear Snake River spring/summer chinook salmon captive broodstocks in seawater at the NMFS Manchester Research Station.  State and Federal involvement in these programs is coordinated through the BPA chaired Chinook Salmon Captive Propagation Technical Oversight Committee (CSCPTOC).

The use of captive broodstock fish to restore anadromous runs of Snake River chinook salmon is an action required to reach objectives of the NWPPC Mountain Snake and Blue Mountain province planning documents, the artificial propagation summary for the Mainstem/Systemwide Province, and the 2000 NWPPC Columbia Basin Fish and Wildlife Program.  In addition, safety net captive broodstocks are among the Reasonable and Prudent Alternative (RPA 175, 176, 177) actions called for in the 2000 NMFS Biological Opinion, and are an ESA mandated item in the NMFS Recovery Plan for Snake River Salmon (Schmitten et al. 1995, 4.1a and 4.1b).  The Oregon (Project 199604400) and Idaho (Project 199700100) components of these cooperative captive broodstock projects were recently reauthorized through the Blue Mountain and the Mountain Snake Provincial review processes.  The NMFS component (Project 199606700) was reauthorized by the NWPPC in July 2003 under the Mainstem/Systemwide Provincial review process.  Continuation of the marine rearing component at Manchester is vital to the overall success of these cooperative projects.

The captive broodstock concept differs from conventional hatchery programs in that fish of wild origin are maintained in captivity throughout their life.  Offspring from captive broodstocks are released to supplement wild populations.  The high fecundity of Pacific salmon, coupled with potentially high survival in protective culture, affords an opportunity for captive broodstocks to produce large numbers of juveniles in a single generation for supplementation (Flagg et al. 1995a,b).  The relatively stable egg supply from captive broodstock programs should help ensure the success of supplementation efforts for depleted stocks.

Idaho programs use an approach, termed captive rearing, that involves rearing broodstock in captivity to adulthood and releasing them back into their natal streams to spawn naturally.  This approach is still under investigation and it is unclear whether hatchery-reared adults will retain the characteristics necessary for successful spawning in the wild.  Because the success of achieving wild-fish attributes is uncertain, it is possible that in some years gametes may also be returned to Idaho to help maintain these gene pools.  The Oregon program use a conventional captive breeding approach where maturing fish are returned to Oregon, spawned, and the resultant eggs used to help maintain and restore these gene pools.

Between 1996 and 2004, NMFS has captively-reared groups of Snake River spring/summer chinook salmon from Idaho and Oregon (Flagg et al. 1997, 1998; McAuley et al. 2000, Maynard et al. 2003 a, b).  Maturity of these fish in captivity between fall 1996 and 2003 resulted in more than 3,583 prespawning adults provided to IDFG and ODFW.  Planning for the current workplan cycle includes continued rearing of the groups of 2000-2002 brood currently on-station at Manchester (see Task 1, below) and transfer and rearing of groups of 2003-brood smolts in spring 2005 (see Task 2, below).  Total project requirements for these activities include 1) seven-day-a-week protective culture for groups of spring/summer chinook salmon from Oregon's Grande Ronde River Basin and Idaho's Salmon River Basin; 2) fish health diagnostics, including necropsies of all mortalities and bacterial and viral testing; 3) participation on Chinook Salmon Captive Propagation Technical Oversight Committees 4) complete work on replacement of seawater pipeline.  NMFS feels that continuation of cooperative captive broodstock programs is imperative to aid recovery of Snake River spring/summer chinook salmon.

EXPECTED RESULTS

Because of the critically low population size, captive broodstocks appear to offer the only hope to maintain critical stocks of Snake River spring/summer chinook salmon while habitat improvements are underway.  Maintaining geographically separate captive brood populations will help reduce the risk of catastrophic loss of these gene pools from mechanical failure, human error, or disease.  In upcoming years, the Snake River spring/summer chinook salmon captive broodstock programs should provide hundreds of adults and hundreds of thousands of eggs for use in recovery efforts.

REFERENCES

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

Flagg, T. A., F. W. Waknitz, and C. V. W. Mahnken.  1995b.  The captive broodstock concept: application to Pacific salmon.  In T. A. Flagg and C. V. W. Mahnken (editors), An assessment of the status of captive broodstock technology for pacific salmon, pages 1-1 to 1-60.  Report to Bonneville Power Administration, Contract DE-AI79-93BP55064.

Flagg, T. A., M. R. Wastel, and W. C. McAuley.  1997.  Manchester spring chinook broodstock project, progress report for 1996.  Report to Bonneville Power Administration, Contract 96-BI-96441, 8 p.

Flagg, T. A., M. R. Wastel, and W. C. McAuley.  1998.  Manchester spring chinook broodstock project, progress report for 1997.  Report to Bonneville Power Administration, Contract 96-BI-96441, 7 p.

Maynard, D. J., W. C. McAuley, and T. A. Flagg. 2003a.  Snake River spring/summer chinook captive broodstock rearing and research, 2001. Report to Bonneville Power Administration, Contract 96-BI-96441.21 p.

Maynard, D. J., W. C. McAuley, and T. A. Flagg.  2003b  Manchester spring/summer Chinook captive broodstock rearing and research, 2002.  Annual Report to the Bonneville Power Administration, Contract 96-AI 96441, project 1696-06700, 25 p.

McAuley, W. C., M. R. Wastel, and T. A Flagg.  2000.  Manchester spring chinook broodstock project, progress report for 1998.  Report to Bonneville Power Administration, Contract 96-BI-96441, 8 p.

Schmitten, R., W. Stelle, Jr., and R. P. Jones.  1995.  Proposed Recovery Plan for Snake River Salmon, 347p., plus appendices.