Comparative Survival Study (CSS) of Hatchery PIT-tagged Spring/Summer Chinook; Migration Years 1997-2000 Mark/Recapture Activities, 2001 Annual Report.

Technical Report · Fri Feb 01 00:00:00 EST 2002

DOI:https://doi.org/10.2172/818851· OSTI ID:818851

Bouwes, Nick ^[1]; Petrosky, Charlie ^[2]; Schaller, Howard ^[3]

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1. EcoLogical Research, Providence, UT
2. Idaho Department of Fish and Game, Boise ID
3. US Fish and Wildlife Service, Columbia River Fisheries Program Office, Vancouver, WA

The Comparative Survival Study (CSS) was initiated in 1996 as a multi-year program of the fishery agencies and tribes to estimate survival rates over different life stages for spring and summer chinook (hereafter, chinook) produced in major hatcheries in the Snake River basin and from selected hatcheries in the lower Columbia River. Much of the information evaluated in the CSS is derived from fish tagged with Passive Integrated Transponder (PIT) tags. A comparison of survival rates of chinook marked in two different regions (which differ in the number of dams chinook have to migrate through) provides insight into the effects of the Snake/Columbia hydroelectric system (hydrosystem). The CSS also compares the smolt-to-adult survival rates (SARs) for Snake River chinook that were transported versus those that migrated in-river to below Bonneville Dam. Additional comparisons can be made within in-river experiences as well comparison between the different collector projects from which smolts are transported. CSS also compares these survival rates for wild Snake River spring and summer chinook. These comparisons generate information regarding the relative effects of the current management actions used to recover this listed species.Scientists and managers have recently emphasized the importance of delayed hydrosystem mortality to long-term management decisions. Delayed hydrosystem mortality may be related to the smolts. experience in the Federal Columbia River Power System, and could occur for both smolts that migrate in-river and smolts that are transported. The CSS PIT tag information on in-river survival rates and smolt-to-adult survival rates (SARs) of transported and in-river fish are relevant to estimation of ''D'', which partially describes delayed hydrosystem mortality. ''D'', or differential delayed mortality, is the differential survival rate of transported fish relative to fish that migrate in-river, as measured from below Bonneville Dam to adults returning to Lower Granite Dam. A ''D'' equal to one indicates that there is no difference in survival rate after hydrosystem passage, while a ''D'' less than one indicates that transported smolts die at a greater rate after release, than smolts that have migrated through the hydrosystem. While the relative survival rates of transported and in-river migrants are important, the SARs must be also be sufficient to allow the salmon to persist and recover (Mundy et al. 1994). Decreased SARs could result from delayed hydrosystem mortality for either transported or in-river migrants, or both. Major objectives of CSS include: (1) development of a long-term index of transport SAR to in-river SAR for Snake River hatchery spring and summer chinook smolts measured at Lower Granite Dam; (2) develop a long-term index of survival rates from release of smolts at Snake River hatcheries to return of adults to the hatcheries; (3) compute and compare the overall SARs for selected upriver and downriver spring and summer chinook hatcheries; (4) begin a time series of SARs for use in hypothesis testing and in the regional long-term monitoring and evaluation program; (5) evaluate growth patterns of transported and in-river migrating smolts, and of upriver and downriver stocks. Primary CSS focus in this report for the 1997-1999 migration years included hatchery chinook tasks for objectives 1, 4 and 5.

• Research Organization: Bonneville Power Administration, Portland, OR (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: 00006203
• OSTI ID: 818851
• Report Number(s): DOE/BP-00006203-2; R&D Project: 199602000; TRN: US200322%%229
• Resource Relation: Other Information: PBD: 1 Feb 2002
• Country of Publication: United States
• Language: English

Related Subjects

13 HYDRO ENERGY
24 POWER TRANSMISSION AND DISTRIBUTION
54 ENVIRONMENTAL SCIENCES
ADULTS
COLUMBIA RIVER
DAMS
EVALUATION
GRANITES
HYPOTHESIS
MANAGEMENT
MONITORING
MORTALITY
POWER SYSTEMS
RIVERS
SALMON
TESTING
TRANSPORT
CHINOOK SALMON - SNAKE RIVER WATERSHED (WYO.-WASH.) - MORTALITY
HATCHERY FISHES - MORTALITY
FISH TAGGING - SNAKE RIVER (WYO.-WASH.)