Dec 17, 2024 · Columbia and Willamette river salmon and steelhead face serious threats from California and Steller sea lions that prey on fish waiting to move up the fish ladders at Bonneville Dam and Willamette Falls and other pinch points.

Speed of GPS-tagged California sea lions and Steller sea lions while in transit between upriver foraging areas (Bonneville Dam, Willamette Falls) and estuary haul-out sites (EMB, South Jetty).

rubber buckshot in attempts to deter sea lions from the Bonneville Dam tailraces (Brown et al. 2010). While thought to be potentially effective at deterring predation by new animals arriving at the dam for the first time, they have been ineffective at deterring predation by …

Oct 30, 2019 · In this case, state resource managers from Oregon, Washington and Idaho are allowed to remove a limited number of California sea lions annually that have been identified as preying on salmon and steelhead in the areas below Bonneville Dam and Willamette Falls.

Satellite transmitters were attached to eight Steller sea lions captured at Bonneville Dam in order to track their movements during the summer breeding season when they are typically absent from the river.

Bonneville Dam, located approximately 235 km (146 miles) upriver from the Pacific Ocean, is the lowermost hydroelectric project on the Columbia River. During the 1980s and 1990s, one to two California sea lions (CSLs; Zalophus californianus) were reported annually at the dam during fishway inspections (Stansell 2004).

Bonneville Dam, located approximately 235 km (146 miles) upriver from the Pacific Ocean, is the lowermost hydroelectric project on the Columbia River. During the 1980s and 1990s, one to two California sea lions (CSLs; Zalophus californianus) were reported annually at the dam during fishway inspections (Stansell 2004).

For six years, state biologists tried to scare sea lions away from the fish below Bonneville Dam using “hazing” techniques such as cracker shells and seal bombs before seeking federal approval to use lethal methods. Hazing temporarily interrupts feeding, but the sea lions resume eating shortly after hazing stops. Efforts to relocate ...

Oct 12, 2016 · California sea lion feeding on a salmon near Powerhouse 2 at Bonneville Dam, May 2005. The U.S. 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 since 2003.

Devices (SPD) to prevent the sea lions from attacking the salmon as they enter the fish ladders at Bonneville Dam. Unfortunately, Steve passed away of cancer in the Spring of 2023.