Protected Species

According to government officials, the hunting of steelhead salmon by California sea lions at Ballard Locks in Seattle, Washington, is the only documented case in which predation by one species is threatening the existence of another, although federal officials suspect that the adverse predation of fish by protected seals may also be occurring at the Columbia River and in the state of Maine. Efforts to counteract the predation at Ballard Lock, including relocating the sea lions and driving them away from the locks, have been unsuccessful. Other possible options include capturing and holding the sea lions during the steelhead's migration and making structural changes to the locks and the accompanying spillway. The National Marine Fisheries Service has considered but rejected the possibility of controlling the sea lion population through lethal means.

GAO found that: (1) although predation by California sea lions is threatening the existence of another protected species, federal officials believe that MMPA-protected sea lions or seals could also be causing adverse predation of fish on the Columbia River and in several Maine rivers; (2) federal efforts to mitigate sea lion predation on anadromous fish at Ballard Locks have included sea lion relocation; (3) attempts to drive away local sea lion populations have been largely unsuccessful; (4) MMPA and ESA do not sufficiently address potential adverse predation in the Columbia River and Maine by MMPA-protected sea lions on ESA-protected salmon populations; and (5) federal agencies need to address conflicting MMPA and ESA provisions which could resolve predation issues and allow temporary or lethal removal of predation species.