[20181212]IF11045_海狮捕食哥伦比亚河鲑鱼和钢头鲑.pdf

https:/crsreports.congress.gov December 12, 2018Sea Lion Predation on Columbia River Salmon and SteelheadSince the 1990s, concerns have grown about sea lion predation on Columbia River salmon and steelhead (salmonids). Management of these species has been complicated by requirements to protect sea lion populations under the Marine Mammal Protection Act (MMPA; 16 U.S.C. 1361 et seq.) while maintaining efforts to recover salmonid populations under the Endangered Species Act (ESA; 16 U.S.C. 1531 et seq.). Sea lion populations have increased since enactment of the MMPA in 1972. In the Columbia River Basin, 13 salmonid runs now are listed as threatened or endangered under the ESA. During the 115th Congress, several bills were introduced that would provide greater flexibility for lethal removal of sea lions in specific segments of the Columbia River and its tributaries. One of these bills, S. 3119, has passed the Senate and the House. Background Sea Lion and Salmonid Populations Over the last several decades, California sea lions (Zalophus californianus) and the eastern population of Stellar sea lions (Eumetopias jubatus) that inhabit the U.S. West Coast have steadily increased. The Cal