Investigations into the [Early] Life History of Spring Chinook Salmon in the Grande Ronde River Basin : Fish Research Project, Oregon : Annual Report 1994 : Project Period 1 June 1993 to 31 May 1994.

This study was designed to describe aspects of the life history strategies of spring chinook salmon in the Grande Ronde basin. During the past year we focused on rearing and migration patterns of juveniles and surveys of spawning adults. The specific objectives for the early life history portion of the study were: Objective 1, document the annual in-basin migration patterns for spring chinook salmon juveniles in the upper Grande Ronde River, including the abundance of migrants, migration timing and duration; Objective 2, estimate and compare smolt survival indices to mainstem Columbia and Snake River dams for fall and spring migrating spring chinook salmon; Objective 3 initiate study of the winter habitat utilized by spring chinook salmon in the Grande Ronde River basin. The specific objectives for the spawning ground surveys were: Objective 4, conduct extensive and supplemental spring chinook salmon spawning ground surveys in spawning streams in the Grande Ronde and Imnaha basin, Objective 5; determine how adequately historic index area surveys index spawner abundance by comparing index counts to extensive and supplemental redd counts; Objective 6, determine what changes in index areas and timing of index surveys would improve the accuracy of index surveys; Objective 7, determine the relationship between number of redds observed and fish escapement for the Grande Ronde and Imnaha river basins