This Statement of Work covers the continuation of the research project entitled "Evaluating relative reproductive success of natural- and hatchery-origin Snake River fall Chinook spawners upstream of Lower Granite Dam".  The goal for this project is to determine whether genetic variation between wild- and hatchery-origin Snake River fall Chinook spawner populations is large enough to allow accurate estimates of their relative contributions to annual natural production, and if so, to estimate wild and hatchery contributions to annual samples of natural origin fall Chinook.  Results since 2005 showed that in most brood years wild-produced fall Chinook were significantly different genetically from Lyons Ferry Hatchery broodstocks.  Lyons Ferry Hatchery produces fall Chinook of Snake River origin, and these hatchery fish have been released in upstream natural spawning areas.  We expect the genetic profile of a wild-origin brood year sample to reflect contributions of hatchery and wild stocks in proportions that occurred in the parent naturally spawning population if relative reproductive success is similar.  We assume that annual hatchery and wild proportions in the upstream spawner population are the same as those estimated in fall Chinook intercepted and sampled at Lower Granite Dam.  Adult spawning ground sampling conducted for this project since 2006 has found very high proportions of hatchery-origin adults compared to wild-origin adults.

The long-term goal of the analytical work is to evaluate whether hatchery-origin fall Chinook are affecting productivity and recovery of the ESA-listed Snake River population, which addresses concerns documented in Federal Columbia River Power System (FCRPS) Biological Opinion Action 182.

For 2009  we will collect DNA genotype data for adult spawners sampled in 2008, and continue with genetic mixture analyses to estimate contributions of hatchery-origin and wild-origin fall Chinook to previous natural production brood years.  We will complete all genetic and statistical analyses involving all samples analyzed during the course of this project. Reports will include summarization of multi-year results.