#IfYouBuildItTheyWillCome!
Less than 60 days after BVFF placed gravel in the river in October, ODFW biologists Dave Banks and Kirk Hanley confirmed that brown trout have used it for spawning! While initial surveys in November showed no activity, the December spawning survey confirmed the news we were hoping for: 22 new brown trout redds in the project zone!
Validating the Count:
Dave and Kirk conducted surveys in both mid-November and mid-December. The lack of redds in November actually proved to be a critical baseline. Because the biologists saw no spawning structures in the new gravel during the first pass, they could be confident that the 22 distinct redds found in December were fresh constructions made by spawning fish, not just "lumpy" gravel left over from the project work.
Immediate Results:
Twenty redds were located in the new gravel section below Sand Hollow Creek, with two more found in the tailout below the bridge a mile downstream. Kirk Handley noted that he was very pleased with the placement of the gravel, confirming that volunteers put it exactly where he would expect fish to spawn.
The Challenge of "New" Gravel:
Identifying these redds required a trained eye. Typically, biologists spot redds by looking for "clean" gravel patches where fish have scrubbed away the river's algae. Because our gravel was only added in mid-October, it hadn't yet grown that algae layer, meaning the "clean spot" indicator wasn't visible. Instead, Kirk and Dave relied on identifying the structural shape of the redds—the tell-tale depression and gravel tailspill.
What This Means for the River:
Kirk told me that he and Dave weren't sure if the browns would find and use the gravel this year given the late timing of the augmentation. Seeing them adopt it so quickly is a massive win. He emphasized that establishing better spawning habitat in the lower river is a key step in helping the population rebound from environmental stressors like warm water events or Saprolegnia fungus.
See the Full Story at the Expo:
We will be featuring the Owyhee Gravel Augmentation project at the BVFF Booth at this year's Western Idaho Fly Fishing Expo (January 30-31). ODFW is helping us prepare posters with more details about spawning trends and their fish relocation study. Stop by the booth to chat with the project leaders and see the data for yourself!
A BIG THANK YOU to everyone who worked on this project—especially the volunteers who run the Expo. BVFF's Fly Fishing Expo is 100% volunteer-run, and 100% of the proceeds go to BVFF's fly fishing education, access and conservation projects.
Help Us Do More:
- Share the below Expo Poster on social media or email it to friends. Better yet, send them a link to this Conservation Blog article!
- Volunteer for a shift at the Expo. Sign up at the Expo Web Page.
More Info:
In case you didn't see it in the previous club Hackle Bender newsletter, here are a few articles about the Owyhee Gravel Augmentation project.
