After 5 years of planning, the Owyhee Augmentation Project is about to happen! After finally getting our permits last winter we thought we were a GO, but the project got delayed due to unexpected high water flows. But we have heard from the Owyhee Irrigation District that flows on the Owyhee are scheduled to drop on October 15th so we will be doing our gravel augmentation the following week--Thursday, October 23rd, which gets it in the river in time for brown trout to use it for spawning this season. The Monday - Wednesday before we will be doing site prep and working with Sunroc/Suncore to stage the gravel.
Our Conservation Team took advantage of the extra time this summer to make some improvements to the plan. One of the big questions about the gravel augmentations that BVFF and TU have done on the Boise River in the past is how long the gravel stays in place. Club member Jeff Jones (a retired geologist) devised a plan to track how the gravel moves downstream during high spring flows. Jeff and I met with scientists from local company Biomark, who specializes in PIT tags for tracking fish. We tested drilling into samples of the gravel and adding a (2mm by 12mm long) PIT tag and then tested to show we could detect them in a bucket of gravel (you can see more about that at this Conservation Blog article). Reviewing the results with biomark scientists Nick Porter and Jake Cryer, they designed a plan to seed tagged gravel in a study plot, to prevent tag interferrence. We plan to tag around 150 pieces of gravel of several sizes classes and place them in 4 different study plots of different depths and velocities of water. #CoolScienceStuff
Each Fall we will use a portable PIT tag reader (that looks a lot like a big metal detector) to sweep the area to identify the locations of the tagged gravel. If, after 5 years, the gravel is staying in place well enough and brown trout are utilizing it for spawning, then we would like to do another gravel augmentation. I personally predict SUCCESS! , based on my observations on the Boise River-- brown trout are very good at finding and using new gravel. And I believe that the gravel will stay in place much better than on the Boise river because of the lower gradient of the Owyhee and less frequent episodes of high flows.
ODFW has conducted fall spawning surveys on the Owyhee for many years and has data on spawning numbers (here is an earlier Conservation Blog that talks more about that). That data shows no spawning activity in the area we plan to add gravel. Hopefully that will change this Fall! Given the brown trout population is much smaller in the lower sections of the river it will take time for the brown trout to fully utilize all the gravel, but I am hopeful that in 5 years we will look down from the road above and see wall-to-wall brown trout spawning, like many of the prime spawning runs in the river above.
This summer, Jeff and I also met with professor Andy Tranmer at the University of Idaho Water Research Center, who specializes in sediment transport in rivers. In addition to tracking gravel movement he recommended we track fine sediments. We are building some sediment traps based on the design of one of his PhD students, Nicole Hucke (THANKS Andy and Nicole!). The sediment traps are PVC tubes with gravel-filled fine mesh bags inside that we will bury next to the tagged gravel. Each year when we the study area with a portable PIT tag reader we will pull the mesh bags and measure the sediments accumulated in the different study plots. This will give some insights into finer sediment accumulations that could be impacting aquatic invertebrates (BUGS!).
You can hear more about these projects at our September and October club meetings. In September, Biomark will be giving a presentation on how PIT tags are being used to track salmon and steelhead (and GRAVEL!) in Idaho, and in October, ODFW Fish Biologists Dave Banks and Kirk Handley will be giving a presentation on the Owyhee River, including some details about our augmentation and hopefully some early insights on their recent brown trout tagging and relocation study.
This has been a complicated project that has taken the club 5 years to put together. It couldn't have happened without volunteers who helped with the many aspects, and the generous funding and donations by many. My thanks to the O SubTeam who has helped with logistics on the final leg of this project: Scott Lenz, Randy James, Greg Hitchcock, Brian Martin, Kent Christensen, and Jeff Jones. There will be some volunteering opportunities posted on our BVFF Events page and emailed out to club members. Some of the areas we need help with are listed below.
For more information on this project, check out our previous conservation blog posts:
VOLUNTEERS
- Jeff Jones needs help drilling gravel and inserting PIT tags. Contact him if you are interested and have experience with a hammer drill. 208.317-1488. Our thanks to Pete Rockwell and and Scott Cheser who have volunteered to help, and to Linda Butts who is helping Jeff sew the mesh bags for the sediment traps.
- Identifying and marking the final gravel augmentation zones earlier in the week.
- Traffic Control the day of the augmentation.
- Gravel Cleanup Crew.
- Water Turbidity monitoring during the project--needed for our water quality permit. If you have experience with a turbidity meter and can help, please reach out to me at conservation@bvff.com.
- Ongoing Augmentation Zone Monitoring. When fishing the O, we would like club members to take a few minutes and document observations below Sand Hollow creek. Report if you see any spawning fish this Fall (BONUS POINTS if you can see if there is a yellow floy tag in their dorsal fin--indicating they are one of ODFW's tagged/relocated fish), or any blowouts at Sand Hollow creek. Please post pictures and comments to our BVFF group Facebook Page (or email me at conservation@bvff.com).
I would like to take this opportunity to thank the partners who are helping us with this project.
Funding for the project provided by:
- Grants from FFI, ODFW and the Snake River Waterkeeper
- BVFF's 2023 Idaho Gives campaign (lead by Brian Martin and Deborah DeSousa)
- Everyone who bought a "Greenback For Redds"
- Suroc/Suncore is providing the gravel at a reduced price
- Biomark is donating PIT tags and letting us borrow PIT tag scanners/readers
- Dave Banks and Kirk Handley from ODFW, who helped us design the project
- The Malheur county BLM who has supported the project. permitting and is letting us stage the gravel at the site
- Owyhee River Ranch who is helping with gravel staging site prep.
