Cowlitz Hooking Mortality Study

In collaboration with Washington Department of Fish and Wildlife and Tacoma Power, Mount Hood Environmental led a three-year angling evaluation on the Lower Cowlitz River in southwest Washington. The objective of the study was to improve the accuracy and regional specificity of hooking mortality estimates used to manage salmon and steelhead sport fisheries throughout the Columbia River basin. Angled fish were marked with external tags and released back into the river. Concurrently, non-angled fish captured at the Cowlitz Salmon Separator were transported back downstream and released into the fishery. The difference in recapture rates of control (non-angled) and treatment (angled) fish was then used to estimate mortality associated with catch-and-release in the fishery. In addition to baseline estimates of mortality, MHE and WDFW estimated impacts of terminal tackle, fishing techniques, and environmental conditions on salmon and steelhead post-release survival.


Washington Department of Fish & Wildlife


Fisheries, Original Research




Cowlitz River, Washington