Fish-eating birds, including Caspian terns, double-crested cormorants, and gulls, are killing half, or more, of the juvenile Upper Columbia steelhead, an ESA threatened species, during their annual outmigration down the Columbia River to the Pacific Ocean.
In a letter to the U.S. Fish and Wildlife Service, the Council describes the problem. The Service is considering a rule change to allow more cormorants to be lethally removed from areas east of the Continental Divide where they threaten fish in hatcheries and rivers. While the rule change would not affect cormorants west of the Divide, the Council wanted to let the Service know predation by cormorants is harming fish in the Columbia River, including ESA-listed species.
The predation by birds is occuring over more than 500 miles of the river, from central Washington state to the ocean, affecting all species of juvenile salmonids (some more than others depending on the length and timing of their migration), and coincides with the birds’ breeding season. Smolts being consumed by these avian predators include at least five Endangered Species Act (ESA)-listed species: Snake River sockeye, Upper Columbia Steelhead and Spring Chinook, and Snake River Steelhead and Spring/Summer Chinook.