Beach and Purse Seine Sampling of Juvenile Salmonids in the Columbia River Estuary and Ocean Plume, 1977-1983. Volume 2. Data on Marked Fish Recoveries

摘要

The National Marine Fisheries Service, partially funded by the Pacific Northwest Regional Commission and Bonneville Power Administration, has conducted extensive beach and purse seine sampling of juvenile salmon, Oncorhynchus spp., and steelhead, Salmo gairdneri, at the upstream entrance of the Columbia River estuary, from 1977 through 1983. The objectives of the sampling were to: (1) define the migrational characteristics of juvenile salmonids to and through the estuary, (2) make various biological observations of migrants, (3) monitor the relative survival of marked fish migrating through the Columbia River, and (4) correlate juvenile catch data with adult recovery information to assist in evaluation of hatchery production techniques and procedures.