Summary of Survival Data from Juvenile Coho Salmon in the Klamath River, Northern California, 2006

Little is known about the survival of ESA-listed juvenile coho salmon during their seaward migration in the lower Klamath River. In 2006, the Bureau of Reclamation funded a study to estimate the survival of radio-tagged juvenile coho salmon in the Klamath River downstream of Iron Gate Dam. A series of models were evaluated to determine if survival varied between hatchery and wild fish and among several river reaches between the dam river kilometer 33, a total distance of 276 kilometers. The results from 2006, the first year of study, indicated little support for differences in survival between hatchery and wild fish and lower survival in the most upstream reach than in those farther downstream. This document is a brief summary of survival results to date.