Filling Data Gaps for Skagit River Steelhead Recovery Planning

Eric Beamer, Research Director, Skagit River System Cooperative

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There are many factors that collectively contribute to Puget Sound steelhead population declines by altering survival and productivity. At a coarse scale these factors span a variety of physical, biological, regulatory and man-caused factors such as unfavorable ocean conditions and harmful hatchery practices. Recognizing that many factors likely contribute to the decline of Skagit steelhead, we initiated two multi-year field-based studies to fill important data gaps for the development of Skagit steelhead recovery planning tools.

The first study (aka Skagit SK Study) focused on a single, yet important factor described as the potential effects of hatchery releases on natural-origin steelhead survival and abundance from an ecological and genetic standpoint. The study results indicate that the segregated hatchery steelhead program currently operating in the Skagit Basin may be negatively impacting the Skagit wild steelhead population. This conclusion is based on potential competition for food and space among hatchery and wild juveniles, and evidence demonstrating gene flow between hatchery and wild populations. The second study (aka Skagit Yearling Salmonid Study) focused on measuring juvenile steelhead habitat preferences and densities throughout the Skagit Basin by life stage and season.

Results from both studies will be incorporated into a life stage-specific model (e.g., Species Life Cycle Analysis Modules) for Skagit steelhead to predict the consequences of integrated recovery plan actions from all H’s (i.e., Hatcheries, Harvest, Habitat, and Hydropower) and to predict the benefits of basin-wide habitat restoration and protection on the wild steelhead population in the Skagit Basin. Ongoing steelhead population monitoring will be used to update model functions in order to improve prediction capability for implemented or planned steelhead recovery actions.