Nez Perce Tribe

Department of Fisheries Resources Management


Fall Chinook Fidelity & Fallback Project

The objective of this project is to determine and compare adult distribution of hatchery origin fall Chinook in the Snake River Basin above and below Lower Granite Dam (LGD).  To accomplish this objective, we plan to:  1) determine fidelity to release location of adults returning from acclimated and direct released subyearling smolts, and 2) quantify fallback at LGD of adults returning from releases of yearling and subyearling smolts from Lyons Ferry Hatchery.

A radio telemetry study will be implemented to accomplish the research objective. Adults will be radio tagged at LGD. Utilizing the Separation by Code (SbyC) from detections of adults at downriver dams, known destination fish can be diverted to the LGD sample room and inserted with radio tags. This will allow for an evaluation of multiple groups of fall Chinook released throughout the Snake River Basin (e.g. Clearwater River and Grand Ronde Rivers). Marking of these groups with PIT tags has been accomplished prior to release (in sufficient numbers to return as adults).  This will allow for an evaluation of each separate group, to be tagged and tracked from LGD to their final destination.

The project will help us better understand the behavior and spatial distribution of returning adults from subyearling and yearling smolt releases. Distribution of hatchery-origin spawners is important for understanding the potential interactions of the supplementation program on natural production. Data on fall back is important when constructing escapement and productivity estimates.  This project works collaboratively with Washington Department of Fish and Wildlife and other co-managers in the Snake River Basin.

Project Staff

peterc@nezperce.orgPeter ClearyProject Leader06(208) 476-4920x3572
brentb@nezperce.orgBrent BroncheauBiologist I12(208) 476-4920x3583
leanderg@nezperce.orgLeander GoodteacherFIsheries Technician II15(208) 621-3567

Project Photos


To view documents associated with this project please visit our Publications Library
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