A five year authorization was granted in three U.S. states to continue trapping and euthanizing sea lions “overfeeding” on salmon populations.
Sea lions reportedly devour large quantities of the salmon and steelhead as they head upstream past the Bonneville Dam on the Columbia River, equating to a decline of as much as 4% of the fish population in the past eight years. Nearly a third of these fish are listed under the Endangered Species Act, leading The National Oceanic and Atmospheric Administration to take drastic action. They have recently granted permission for the removal of harmful sea lions in the states of Oregon, Washington, and Idaho.
Efforts to temper the sea lion population have previously included firing rubber buckshot, implementing hydroelectric gates, and using pyrotechnics displays to dissuade the animals from climbing the dams and feeding on the salmon, but none of these have been applicably successful.
In 2008 an initial authorization allowed for the trapping and removal of a small number of noticeably detrimental sea lions; those captured designated for placement in aquariums or zoos. When numbers exceed captivity options, however, these animals are allowed to be humanely euthanized.
More than 300,000 sea lions live along the west coast and since the original sanction 166 animals have been removed, equating to the survival of nearly 20,000 fish. This new authorization will run until 2021 and more definitively depress the overwhelming sea lion population.
Since the beginning of 2016, 59 sea lions have been removed. The maximum number of animals allocated for expulsion is 92 per year.
Unfortunately, the real problem facing salmons is the construction of dams. According to the Northwest Power and Conservation council website, “Dams block passage of salmon and steelhead between spawning and rearing habitat and the Pacific Ocean. Where fish passage is not provided the blockage is permanent. More than 55 percent of the spawning and rearing habitat once available to salmon and steelhead in the Columbia River Basin is permanently blocked by dams.”