The authorization will run for five years, through June 30, 2021. It is one of many actions underway across the Columbia Basin to address impacts on imperiled salmon and steelhead, including impacts from hydroelectric dams, hatcheries, harvest, habitat degradation, and other predators.
Section 120 of the Marine Mammal Protection Act allows NOAA Fisheries to authorize the lethal removal of individually identifiable sea lions or seals that are having a “significant negative impact” on salmon and steelhead listed under the Endangered Species Act. Sea lions at Bonneville dam prey on five threatened and endangered salmon and steelhead stocks, and the recovery plan for highly endangered upper Columbia spring Chinook salmon calls for continued control of predator impacts.
Last year sea lions were estimated to have consumed nearly 10,000 adult spring Chinook salmon, amounting to more than 3 percent of returning adult fish. The impact on individual populations within the run may be much higher. An estimated 25 to 35 percent of the fish consumed are listed under the Endangered Species Act.
In their application for the authorization, the states noted that the number of sea lions in the area and their consumption of protected salmon has increased since 2013 and lethal removal must continue “to prevent these stocks from becoming further depressed.”
NOAA Fisheries first granted the states authorization under MMPA Section 120 to remove sea lions in 2008. Litigation interrupted the effort, but the states reapplied for authorization in 2011. In 2012, NOAA Fisheries authorized the states to remove up to 92 California sea lions each year for five years.
The states have removed 166 animals since the effort began in 2008. The most California sea lions removed in a single year so far has been the 59 animals removed in 2016. Removing sea lions is a last resort after actions have been tried to deter individual animals habitually preying on salmon. The states may euthanize animals if no permanent holding facility, such as a zoo or aquarium, can be found.
The states estimated in their application that sea lion removals at Bonneville Dam have prevented the loss of 15,000 to 20,000 salmon and steelhead.
In January, the states applied to NOAA Fisheries to extend the authorization issued in 2012 for five more years. NOAA Fisheries took public comment on the proposal beginning in March, analyzed the environmental effects, and convened a meeting of its Pinniped-Fishery Interaction Task Force to provide input before deciding to approve the states’ application and issue a new Letter of Authorization (LOA).
The new LOA is functionally identical to the 2012 LOA. The states may remove sea lions only after other methods of deterrence, such as hazing, have proved unsuccessful. Animals identified for removal must also have been repeatedly sighted in the area of Bonneville Dam’s fish ladders, and have been observed consuming salmon.
The California sea lion population on the West Coast of the United States numbers about 300,000 animals. Sea lions that consume salmon on the Columbia River are mostly adult males that travel north from California and spend winter in the Northwest before returning to California in late spring.
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