Nonnative game fish escapement from Reclamation reservoirs

Project ID: 1775
Principal Investigator: Raymond Bark
Research Topic: Ecosystem Needs
Funded Fiscal Years: 2017
Keywords: None

Research Question

Does live escapement of nonnative game fish from Reclamation reservoirs have deleterious effects to native fish that inhabit the same upstream or downstream waters?
Common game fish such as the largemouth bass, smallmouth bass, striped bass, northern pike, channel catfish, black bullhead, brown bullhead, bluegill, yellow perch, black crappie, pumpkinseed, rock bass, brown trout, brook trout, lake trout, and rainbow trout prey on smaller native fish. Therefore, management strategies, guidelines and technological methods need to be developed to eliminate nonnative game fish escapement in effort to conserve native fish, especially for endangered and threatened fish inhabiting the same waters.

Need and Benefit

Live escapement of nonnative game fish from Reclamation reservoirs can have deleterious effects to native fish that inhabit the same waters. Escapement of nonnative game fishes from reservoirs is often by movement over spillways during high flow or from passage through shallow-water discharge structures. Fish escapement from reservoirs with hypolimnial discharges, even at relatively shallow depths of 33-65 feet, is much reduced in comparison with escapement through littoral zone discharges. Reclamation facilities will be identified where nonnative fish impacts to Endangered Species Act listed native fish species is occurring. Pro-active action to reduce or eliminate nonnative fish impacts will reduce long-term costs and consequences of listed fish species recovery efforts. If Reclamation takes no action, further litigation for listed fish species recovery efforts will be inevitable.

Contributing Partners

Contact the Principal Investigator for information about partners.

Research Products

Bureau of Reclamation Review

The following documents were reviewed by experts in fields relating to this project's study and findings. The results were determined to be achieved using valid means.

Nonnative game fish escapement from Reclamation reservoirs (final, PDF, 1.4MB)
By Raymond C. Bark
Research Product completed on September 30, 2017

This research product summarizes the research results and potential application to Reclamation's mission.

Nonnative game fish escapement from Reclamation reservoirs (final, PDF, 1.4MB)
By Raymond C. Bark
Research Product completed on September 30, 2017

This research product summarizes the research results and potential application to Reclamation's mission.


Return to Research Projects

Last Updated: 4/4/17