By Christina Schmidt, Wyoming Game and Fish Department Sheridan Region public information specialist and Nick Scribner, WGFD fish passage coordinator
This year, the Wyoming Game and Fish Department’s fish passage program celebrates its 10th anniversary. Fish passage projects have taken place in Wyoming for many years, but the program was formalized in 2009, creating a small staff and a set of priorities for streams statewide.
Fish passage involves maintaining or reestablishing the ability of fish to move up or downstream to seek out spawning areas, find relief from high water temperatures or low stream flows and locate good cover to over winter. Improving or protecting fish movement along a stream corridor can expand habitats available to multiple species and age classes of fish as well as improve the productivity of a fishery by increasing reproduction, survival or the food supply available in a fish community.
Depending on the unique passage situation and fish species involved with a project, an angler may expect a new fish passage project to potentially improve the quality of a fishery, allow better recovery of a fishery after a disturbance to a section of stream — from flooding, dewatering, sedimentation — or present a new opportunity to pursue a unique species that might not otherwise occur in a system.
At least 120 fish passage projects have taken place in Wyoming in the last decade. These projects include the creation of rock ramps that level out steep areas by creating a more gradual incline for fish to move upstream, installation of fish ladders that allow fish to maneuver around dams or obstacles and other structural improvements.
Another unique structure that allows fish to navigate around barriers is a bypass channel and one of the best examples in the state is in the Sheridan Region.
The Kendrick Dam, north of Arvada, was constructed on lower Clear Creek in 1913, creating a reliable source of water for irrigation and livestock. However, its creation also ended the ability of the creek’s fish to access water above the dam. For almost a century, the dam was the endpoint of travel for any fish attempting to move upstream from the lower reaches of Clear Creek, the largest tributary of the 430-mile Powder River, which is considered the last major undammed prairie stream in the country.
But in April 2010, a fish passage project was completed by the Wyoming Game and Fish Department in cooperation with the current landowner, Pee Gee Ranch. Using a natural bend in the creek, a rock-lined bypass channel was dug below the dam, connecting the two sides of the creek. This 800-foot trench now allows fish to access 36 additional upstream miles of Clear Creek.
At the time of the passage project’s planning and construction, Sheridan Region fish biologists identified 20 fish species they expected would benefit from the bypass channel. Some of the fish they believed had been completely lost upstream of the dam included channel catfish, sauger, goldeye, river carpsucker, flathead chub, Western silvery minnow, plains minnow, sturgeon chub and shovelnose sturgeon. But the fish quickly discovered the new channel and within three years of the project’s completion, 16 of the 20 species were documented upstream of the diversion. At this time, only shovelnose sturgeon remain to be documented.
To learn more about the fish passage program and specific projects, including in the Sheridan Region, please pick up a copy of the August 2019 Wyoming Wildlife magazine.