Evaluation of Juvenile Salmonid Outmigration and Survival in the Lower Umatilla River Basin, Annual Report 2000-2001.

White, Tara C. ; Jewett, Shannon M. ; Hanson, Josh T.

Oregon. Department of Fish and Wildlife.

关键词: Ponds;    Abundance;    Diseases;    Monitoring;    Dams - Environmental Aspects - Oregon - Umatilla River Watershed;   

DOI  :  10.2172/825342
RP-ID  :  DOE/BP-00004340-3
RP-ID  :  00004340
RP-ID  :  825342

美国|英语

来源: UNT Digital Library

【 摘 要 】

This is the seventh year of a multi-year project, monitoring the outmigration and survival of juvenile salmonids in the lower Umatilla River. This project both supplements and complements ongoing and completed work within the Umatilla River basin. Knowledge gained on juvenile outmigration and survival assists researchers and managers in adapting hatchery practices, flow enhancement strategies, canal and fish ladder operations, and supplementation and enhancement efforts of natural and restored fish populations. Findings from this study also measure the success of upriver habitat improvement projects and provide an overall evaluation of the Umatilla River fisheries restoration program. The general objectives for 2001 were to: (1) Estimate migrant abundance and survival and determine migration parameters of PIT-tagged hatchery and natural juvenile salmonids; (2) Monitor natural production and estimate overall abundance of pacific lamprey, chinook and coho salmon and summer steelhead; (3) Assess the condition and health of migrants and determine length-frequency distributions through time; (4) Investigate the effects of canal and fishway operations and environmental conditions on fish migration and survival; (5) Investigate and implement improved tag monitoring capabilities; and (6) Participate in planning and coordination activities within the basin and disseminate results. More specifically, 2001 objectives included the ongoing evaluation of migrant abundance and survival of tagged hatchery fish groups from various species-specific hatchery, rearing, acclimation and release strategies; fourth year reach survival results; continuation of transport evaluation studies; outmigrant monitoring and estimation of natural abundance, and further investigation of the effects of canal operations, environmental factors, fish condition and health on migration, abundance and survival. Some of the key findings for 2001 are: (1) A significant decline in outmigrant abundance of natural salmonids compared with the upward trend of previous years; (2) An undetermined number of hatchery summer steelhead are overwintering in the Umatilla River and migrating out as 2-year old smolts; (3) Transported fish may have a survival advantage over non-transported fish; (4) Migrant survival of fish from the Little White, Carson and Herman Creek hatcheries may have been influenced by disease in 2001; (5) Acclimation may benefit migrant survival of subyearling fall chinook; (6) Overwintering of spring chinook in acclimation ponds may not provide a survival advantage over standard-acclimated fish; and (7) Fish sampled in 2001 tended to be descaled and injured at a higher rate compared with previous years.