Theses and Dissertations Collection

Understanding population migration trends is of importance to fisheries managers especially for populations listed under the Endangered Species Act. In recent years passive integrated transponder tags (PIT) have been increasingly used to monitor tributary escapement of adult summer Steelhead (Oncorhynchus mykiss) returning to the Upper Columbia River, but do not fully characterize behavior and survival. We evaluated the migration, overwintering distribution, and survival of Upper Columbia using radio telemetry. Additionally we monitored post spawn exit from spawning tributaries (“kelting” rate). We also analyzed the efficacy of newly developed, gastrically implanted acceleration sensing tags applied with the primary aim of detecting spawning behaviors. Using video observations, we collected movement data from telemetered steelhead within an enclosure. We developed criteria for analyzing acceleration data to infer the behaviors of tagged steelhead, released at-liberty in the natural environment. Monitoring of at-liberty steelhead revealed spawning behaviors similar to those observed among enclosure steelhead.