Abundance, Productivity, and Life History of Fifteenmile Creek Steelhead

The Fifteenmile Creek Winter steelhead population is considered the most inland winter race of steelhead in the Columbia River Basin.  This population has been identified as a “must have viable” by the Interior Columbia technical recovery team (ICTRT) reaching viable status is essential for achieving DPS delisting.  The ICTRT, Recovery Plan, and the FCRPS BiOp have all identified this population as high priority for improving precision and accuracy of abundance, productivity, diversity and spatial structure information.  This proposal is designed to be implemented by ODFW to establish a comprehensive monitoring and evaluation program for abundance, productivity, and life history of steelhead in the Fifteenmile Creek population, which is ESA listed as a component of the Mid-Columbia steelhead distinct population segment (DPS).  This work is critical to gaining a better understanding of the status of the population and DPS, monitoring and adapting recovery actions, and improving the knowledge of steelhead critical habitat. This project is designed to provide information for the following key performance metrics: recruits-per-spawner; age structure, hatchery fraction; adult life history characteristics; juvenile life history characteristics; smolt abundance; smolt migration survival; smolt-to-adult survival; smolts-per-spawner; spawner distribution; relationship of adult abundance estimates from redd counts and weir counts.  The work proposed includes: 1) installation and operation a weir, adult traps, to assess adult escapement; estimate productivity as adult recruits per spawner; determine the proportion of returns that are hatchery origin strays; determine adult life history patterns; 2) operate a screw trap to: estimate juvenile (smolts and pre-smolts) abundance: mark smolts for survival and migration characteristics assessment; 3) conduct spawning surveys to determine spawner distribution and for redd based escapement estimates;  4) install and operate PIT tag interrogation sites to monitor movement.  Data analyses will integrate life stage specific survival and life history information to derive and assess the key performance metrics.  The information generated from this project will not only significantly improve the quality of the viability status assessments but will also serve as a basis for evaluating long term changes in productivity that result from tributary habitat improvement.  This project is a long term endeavor that will span multiple steelhead generations.