FINDING YOUR WILD SIDE: PRODUCTION OF WILD-LIKE SALMONIDS  

Salmonid declines in the Pacific Northwest of the United States led to an explosion of salmon hatcheries in the late 19^th century to support recreational, commercial, and tribal harvests. At that time hatcheries were more concerned with quantity than quality of the fish released. Over time a controversy grew regarding the impact of hatchery salmonids on wild fishes. Comparisons showed differences in growth, condition, behavior, and migration between hatchery and wild salmonids.

We investigated how hatchery conditions shape the fish we produce. We show how diet, feeding rate, substrate, density, temperature, flow, and structures can be used to produce fish in a hatchery that look more like wild individuals and migrate downstream. Our hatchery program rears ESA listed spring Chinook Salmon Oncorhynchus tshawytscha and winter Steelhead Oncorhynchus mykiss for researchers and conservation. Our fish have been evaluated on phenotype, growth, condition, behavior, osmoregulatory ability, juvenile passage, and migration timing through morphometric analyses, behavioral trials, seawater challenges, and field studies.