Fish Passage Improvement
As part of the BLM’s efforts to improve fish habitat, the Fisheries Program is addressing fish passage problems that occur at stream culverts associated with the 78,000 miles of roads on BLM-managed lands. The agency also works to eliminate passage problems at water diversions, channel head-cuts, and low water stream crossings.
Fish movement is vitally important to many species. Anadromous and other native fishes must be able to move to traditional spawning areas and/or seasonal micro-habitats to complete critical life-cycle requirements such as reproduction and overwintering. In addition, fish movement helps maintain adequate gene flow within and among populations.
The BLM’s Fisheries Program is working with its State, Federal, and private partners, focusing its efforts on high priority species throughout the West. This work includes identifying problematic sites through inventories, designing solutions to fix impediments, constructing new crossings on priority sites, researching the effectiveness of “fish friendly” culvert designs, and maintaining and monitoring projects using adaptive management.
The BLM Fisheries Program works cooperatively with the national Federal Fish Passage Steering Committee to maximize all Federal fish passage efforts, and to date, the Program has resulted in numerous culvert assessments and effectively eliminated hundreds of fish passage barriers.
The BLM is also using funding from the American Recovery and Reinvestment Act of 2009 (ARRA) to hire local contractors for culvert replacement projects. An example is a BLM Eugene, Oregon, District ARRA project which is replacing 11 culverts to enhance passage of fish species, including the federally-listed Coho salmon.
Case Study: Muddy Creek Culvert Project Reconnects 19 Miles of Fish Habitat in Wyoming
On Wyoming’s Muddy Creek, home to four sensitive fish species, BLM was able to reconnect 19 miles of stream habitat to the main river channel by replacing a road culvert that was acting as a barrier with a bridge that allows fish passage. The new bridge, shown left, allows for natural channel migration and is sized such that the natural floodplain characteristics are maintained during high flows.
The native fish of the Muddy Creek watershed have experienced dramatic declines and several species extirpations. Muddy Creek contains both warmwater and coldwater habitats for four BLM sensitive species: bluehead sucker, flannelmouth sucker, and roundtail chub (warmwater species) and the Colorado river cutthroat trout (coldwater species). It is the only stream system in Wyoming where all of these native species coexist.
In 2009, Wyoming Game & Fish Department and BLM treated approximately three miles of the waters downstream of the culvert on Muddy Creek to remove competing nonnative fish and restore native warmwater and coldwater fisheries. (The chemical drip station is shown at right.) Next steps include channel restoration and addressing other barriers in the watershed. In the meantime, BLM Wyoming’s Rawlins Field Office is working with partners such as Wyoming Game & Fish Department, Trout Unlimited, and Little Snake River Conservation District to improve riparian and aquatic habitat in the area.
Sheet piling structures (below) function as a barrier to aquatic organisms. The BLM is working with other stakeholders to modify or remove the structures so that fish passage is improved and riparian integrity is maintained.
The new bridge replaces this culvert, shown at right. The culvert is undersized and has caused extensive channel scouring downstream. The culvert blocked four BLM sensitive fish and other native fish species.
Case Study: BLM-Montana Protects Yellowstone Cutthroat Trout in Crooked Creek
Sometimes, instead of removing a fish barrier, it is necessary to create one in order to protect a fish species. That is what the BLM Billings, Montana, Field Office did to protect a genetically pure Yellowstone cutthroat trout from potential extinction. Yellowstone cutthroat trout are the State Fish of Montana, designated a Sensitive Species by the BLM and Forest Service, and named a Species of Concern by the State of Montana.
The project is a cooperative effort with Montana Fish, Wildlife and Parks and Custer National Forest, and support from Trout Unlimited, Magic City Fly Fishers and Champions for Trout.
Crooked Creek is a 19-mile long tributary to Bighorn Reservoir in Montana’s Pryor Mountains. The barrier was needed to protect a population of Yellowstone cutthroat trout that was threatened by predation, competition and hybridization from several species of non-native trout. A debris flow from a recent fire had eliminated the natural barrier and over half of the population. The project goals were to protect this strain of trout and allow the population to expand downstream into 6 stream miles of secure habitat.
This concrete structure replaces a natural barrier that was washed out and keeps the Yellowstone cutthroat trout; a native, sensitive species; separated from non-native rainbow and brown trout. The structure does not impede water flow.