Corps Message: Sea lion predation at Bonneville Lock and Dam

Sea lion predation at Bonneville Lock and Dam (Corps of Engineers photo)

Sea lion predation at Bonneville Lock and Dam (Corps of Engineers photo)

Predominantly male California and Steller sea lions swim up the Columbia River to Bonneville Lock and Dam in mid- to late-February to eat part of the annual spring migration of sturgeon, salmon, steelhead and other anadromous fish.  They do this to gain weight and energy for the spring mating season and leave by mid-May.

  • The Corps’ role in sea lion issues at Bonneville Lock and Dam Project is limited to monitoring sea lion numbers and predation; evaluating the effectiveness of management techniques; and keeping sea lions out of our fishways.
  • While the Corps operates the dam and the fishways, NOAA Fisheries Service has responsibility for sea lions under the Marine Mammal Protection Act, and the state fish and wildlife departments have hands-on responsibility for any animal within their borders.
  • The Corps has contracted with U.S. Department of Agriculture’s Wildlife Services to harass sea lions from the dam structure to keep them away from the fishway entrances. Wildlife Services is not shooting or killing sea lions.

Steller sea lions – which can be hazed but are currently protected from removal – are having an increasing impact on white sturgeon below Bonneville.