Written by Will Lubenau, University of Idaho
As steelhead fishing begins to wrap up for this spring, we wanted to provide an update on the University of Idaho steelhead catch-and-release study. Like many things, the study has been influenced by the COVID-19 pandemic. Tagging that was occurring at Lower Granite Dam had to end sooner than planned, but fortunately we did tag an additional 43 fish this spring.
A grand total of 1,280 fish were tagged from July 1, 2019 to March 19, 2020. Of the 1,280 tagged fish, 254 have been caught, released, and reported as of March 31, 2020.
We continue to rely on anglers to make this project work so please gather up any tags you caught this steelhead season and report them immediately. To report a tag please go to https://idfg.idaho.gov/fish/tag/add.
If you recall previous project updates, all fish tagged with orange T-bar tags (see picture above) for this study also had a PIT tag implanted internally (for more information on PIT tags click here). These PIT tags are now generating data for our project and helping us estimate survival of the project steelhead to their spawning areas. As wild steelhead now move up to spawn, they are being detected on in-stream PIT tag detectors. The detectors lay on the bottom of streams in a wide variety of locations in the Snake River basin in Washington, Oregon, and Idaho.
A total of 547 of our study fish have been detected at PIT tag detectors as of April 15, 2020. Tagged fish have been detected at 48 locations in the basin! The South Fork of the Clearwater River, upper Grande Ronde River, Imnaha River, Joseph Creek, and upper Salmon River have had the highest number of PIT tag detections.
We have had some of our tagged fish show up at some unexpected locations as well. For example, one fish was tagged at Lower Granite Dam and later returned to the John Day River to spawn. Additionally, one fish had finished spawning and was on its way back to the ocean (for more on repeat spawning steelhead click here) when it was captured in a screw trap that is used to sample juvenile salmon and steelhead in the Potlatch River (pictured below). We will continue to monitor our study fish as spring progresses.
Hope you all are staying safe and healthy! For more information on IDFG’s Wild Salmon and Steelhead Program click here to visit the Wild Salmon and Steelhead Webpage.