Shasta River Brood Year 2012 Juvenile Coho Salmon PIT Tagging Study

This report summarizes PIT tag data collected on brood year 2012 coho in the Shasta River (the progeny of adult coho that spawned in 2012). The key findings of this study were: 1. Overall known survival of PIT tagged BY2012 coho, from the time they were tagged in upper Shasta River in 2013 to outmigration into the Klamath River in the spring of 2014, was 33%. 2. Over 70% of the coho fry tagged in the upper Shasta River downstream of Big Springs Creek migrated upstream in May and June 2013 when stream temperatures increased to ~20 C. 3. Coho utilized a small spring complex adjacent to the Shasta River downstream of Parks Creek as short term thermal refugia during May and June 2013. 4. Successful summer rearing occurred in areas with cold spring inflows, including Little Springs Creek. 5. Overall, known survival was lowest during winter with the poorest winter survival occurring in Big Springs Creek. 6. Outmigrating coho smolts that were known to be alive in the upper Shasta River in March 2014 survived to reach the Klamath River at a rate of 90%, which is higher than documented in the BY2010 study (77%).