SALEM, Ore.— As part of an on-going effort to protect endangered and threatened Columbia and Snake River salmon and steelhead, fish managers in Oregon, Washington and Idaho have jointly applied to the National Marine Fisheries Service for permission to use lethal means, if necessary, to remove individual California sea lions that prey on chinook salmon and steelhead below Bonneville Dam.
The application was submitted today under Section 120 of the Marine Mammal Protection Act, which allows lethal removal of individual pinnipeds that negatively impact federally protected salmonid stocks. Upper Columbia River spring chinook are listed as endangered under the federal Endangered Species Act (ESA); lower Columbia River chinook and steelhead, middle Columbia River steelhead, Snake River spring/summer chinook, and Snake River Basin steelhead are all listed as threatened under the ESA.
Despite non-lethal efforts by Oregon and Washington to discourage them, the number of California sea lions entering the Columbia River—and their rate of predation on ESA-listed salmon and steelhead below Bonneville Dam—has increased in recent years, according to surveys by the U.S. Army Corps of Engineers.
The Section 120 application is subject to a review process that includes consideration by a task force composed of state and federal agencies, tribes, scientists, representatives of conservation and fishing groups and other organizations. The review process could take several years.
Meanwhile, U.S. Reps. Doc Hastings, Brian Baird and Norm Dicks of Washington and Greg Walden of Oregon have introduced legislation in Congress to allow the states and Columbia River Indian tribes to remove sea lions with lethal means from the six-mile area downstream of Bonneville Dam as early as next spring.
“Lethal removal is a management method we prefer not to use, but one that may be necessary to restore balance to the Columbia River ecosystem where threatened and endangered stocks of salmon and steelhead are being preyed on by a healthy and growing population of California sea lions,” said Guy Norman, regional director for the Washington Department of Fish and Wildlife’s (WDFW) Southwest Washington office.
If the Section 120 application is approved, the states could remove a limited number of California sea lions annually from the six miles of river below Bonneville Dam, as well as marked animals that have been observed preying on salmonids that often congregate at Bonneville Dam prior to moving upriver. Any lethal removal would be preceded by a period of non-lethal deterrence activity to give animals a chance to leave the area, and would be followed by an evaluation period. The number of animals removed would depend on a variety of factors. The proposed lethal removals would not include Steller sea lions, a protected species.
“Our primary goal is to change behavior of the animals. We hope to do as much of that as possible with non-lethal means, and use lethal removal as a management tool when necessary to protect endangered and threatened salmon and steelhead,” Norman said.
The states plan to continue hazing efforts aimed at driving sea lions from the area below the dam. In 2005 and again last spring, Oregon and Washington, Columbia River tribes, the Army Corps of Engineers and NMFS jointly attempted a variety of tactics to haze sea lions away from the area below the dam, where returning adult spring chinook salmon and steelhead congregate before making their way up the dam’s fish ladders. Despite last spring’s intensified hazing effort that included firecrackers, acoustic devices and boat hazing, the sea lions returned to the area within a short period.
“We will continue the hazing actions to remove sea lions, but if they are ineffective, we need to be able to go to the next step to protect threatened and endangered salmon and steelhead populations,” said Oregon Department of Fish and Wildlife (ODFW) Conservation and Recovery Program Manager Charlie Corrarino.
According to Corrarino, ODFW and WDFW are planning to conduct non-lethal hazing seven days a week beginning in March 2007, a change from the four days on, four days off schedule used in 2006.
“We believe this to be a responsible approach to managing natural resources,” said WDFW Director Jeff Koenings, Ph.D. “A full range of methods, applied appropriately and humanely, is required to actively manage wildlife populations.”
California sea lion numbers have burgeoned since the 1970s. A September wildlife survey by WDFW documented 1,200 California sea lions at the mouth of the Columbia River, among an estimated West Coast population of 300,000 animals.
Since 2003, the Army Corps of Engineers has documented approximately 100 California sea lions annually consuming an average of 3,000 spring chinook salmon and steelhead at Bonneville Dam, some 145 miles upstream from the Columbia River mouth. The Corps’ estimates do not include losses of salmon and steelhead in other areas of the basin where sea lion predation occurs.
See WDFW's website for additional information on Columbia River sea lions.