Inland Avian Predation Management Plan
The U.S. Army Corps of Engineers (Corps) is currently leading an effort to develop an Inland Avian Predation Management Plan for managing birds (avian predators) that prey on Endangered Species Act (ESA) listed fish species in the Columbia and Snake Rivers. This effort by the Corps, Bonneville Power Administration, and the Bureau of Reclamation (the Action Agencies) is part of the overall efforts to comply with the Federal Columbia River Power System (FCRPS) biological opinion from the National Marine Fisheries Service (NMFS) and will incorporate the necessary National Environmental Policy Act (NEPA) documents.
The Inland Avian Predation Management Plan will incorporate management of bird species identified through recent research efforts to be having the highest predation on juvenile salmonids during their outmigration on the Columbia River upstream of Bonneville Dam. This includes the eight federal Columbia and Snake River dams and adjacent inland areas in Oregon, Idaho, and Washington (Columbia Plateau). As part of developing the plan, the geographic scope will also include those areas where potential habitat for bird relocation may occur throughout the Pacific Northwest.
Recent scientific studies suggest that the most significant impact of avian predation on the Columbia Plateau is occurring by certain avian species including Caspian terns (Hydroprogne caspia) and double-crested cormorants (Phalacrocorax auritus). These studies have identified nesting colonies of terns at Goose, Crescent, and Blalock Islands and cormorants at Foundation Island as contributors to predation on ESA-listed salmonid species in the Columbia River. These studies have also identified other predatory bird species in the area including American white pelican (Pelecanus erythrorhyncos), California gull (Larus californicus), and ring-billed gull (Larus delawarensis) that are having a lesser impact on out-migrating anadromous salmonids. In comparison to terns and double-crested cormorants, these birds appear to have lower predation impacts on salmon and steelhead.
Federal Columbia River Power System Biological Opinion
A biological opinion from the NMFS directs the Corps, Bonneville Power Administration, and the Bureau of Reclamation (the Action Agencies) to address avian predation within the FCRPS as part of an Inland Avian Predation Management Plan. In particular, NMFS has directed the Action Agencies to address inland avian predation through three Reasonable and Prudent Alternatives (RPA's) including:
- The Action Agencies will develop an avian management plan for Corps-owned lands and associated shallow-water habitat.
- The Corps will continue to implement and improve avian deterrent programs at all lower Snake and Columbia River dams. This program will be coordinated through the Fish Passage Operations and Maintenance (FPOM) group and be included in the Fish Passage Plan (FPP).
- The Action Agencies will monitor avian predator populations in the Mid-Columbia River and evaluate their impacts on outmigrating juvenile salmon and steelhead and develop and implement a management plan to decrease predation rates, if warranted.
NMFS recommends strategies to improve juvenile salmon and steelhead survival with the expectation that this will contribute to an improvement in adult returns and thereby recovery of ESA-listed fish species. Managing avian predators to address salmon predation would add to and complement other recovery efforts, thereby contributing to the overall recovery of ESA-listed salmonids in the Columbia River Basin. This management plan will focus on management of lands and associated shallow-water habitat while improvement of deterrent programs at the Corps lower Snake and Columbia River dams will continue to be addressed through the Fish Passage Operations and Maintenance (FPOM) group and the Fish Passage Plan (FPP).