Why are California sea lions a concern on the Columbia River?
In recent years, a growing number of California sea lions in the Columbia River have been preying on endangered and threatened stocks of salmon and steelhead that are protected under the federal Endangered Species Act (ESA). Sea lion predation occurs throughout the lower river system, but the problem is especially acute below Bonneville Dam where returning salmon and steelhead congregate as they prepare to move up the dam’s fish ladders to spawn upstream. Sea lions also prey on mature sturgeon below Bonneville Dam, and on listed salmon and steelhead runs in the Willamette River and other tributaries to the Columbia River.
In the first half of this decade, a growing number of California sea lions in the Columbia River have been preying on endangered and threatened stocks of salmon and steelhead that are protected under the federal Endangered Species Act (ESA). Sea lion predation occurs throughout the lower river system, but the problem is especially acute below Bonneville Dam where returning salmon and steelhead congregate as they prepare to move up the dams fish ladders to spawn upstream. Sea lions also prey on mature sturgeon below Bonneville Dam, and on listed salmon and steelhead runs in the Willamette River and other tributaries to the Columbia River.
