Protected Species:

Marine Mammals' Predation of Varieties of Fish

RCED-93-204: Published: Sep 10, 1993. Publicly Released: Oct 14, 1993.

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Pursuant to a congressional request, GAO reviewed predation by Marine Mammal Protection Act (MMPA) and Endangered Species Act (ESA)-protected species on other nonprotected species, focusing on: (1) whether predation by MMPA- or ESA-protected species was threatening the existence of another species; (2) efforts undertaken to address adverse predation; and (3) whether current laws can adequately resolve adverse predation by protected species.

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.

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