Shasta River Brood Year 2013 Juvenile Coho Salmon PIT Tagging Study

This report summarizes passive integrated transponder (PIT) tag data collected on brood year 2013 (BY2013) juvenile coho in the Shasta River (the progeny of adult coho that spawned in 2013). The key findings of this study were: 1. Overall known survival of the 647 BY2013 PIT tagged coho, from the time they were tagged in the upper Shasta River in 2014, to outmigration into the Klamath River in the spring of 2015 was
22%. 2. Four percent (n=27) of the BY2013 coho PIT tagged in the upper Shasta River outmigrated between May 26 and June 26 in 2014. Based on their size and appearance, we consider these fish to be age-0 smolts.
3. During residency in the Shasta River, overall seasonal survival of PIT tagged juvenile coho in the upper Shasta River was similar from season to season, ranging from 61% in the summer to 72% in the winter.
4. Known summer survival of 144 PIT tagged juvenile coho relocated from Parks Creek to Kettle Spring (67%) was similar to known summer survival of 49 tagged coho that were naturally occurring in Kettle Spring (71%). This was higher than known summer survival of 22 coho tagged and released in Parks Creek without being relocated (9%), likely due to habitat conditions. 5. Known survival of age-1 smolts encountered in February 2015 (or later) and then again at RKM 1 as they outmigrated to the Klamath River was 67%. This is lower than smolt survival to outmigration documented in the BY2010 study (77%) and the BY2012 study (91%).