SEQUIM — A plan to disperse part of the world’s largest colony of Caspian terns will likely bring more of the fish-eating birds from the mouth of the Columbia River — where the protected birds prey on equally protected baby salmon and steelhead — to Dungeness National Wildlife Refuge.
Will more terns be a threat to local fish populations, including two endangered salmon runs?
The U.S. Fish and Wildlife Service says no — but it also plans to monitor the birds closely to make sure.
The $2.4 million proposal calls for expanding five existing nesting sites in Oregon and California and establishing one new area.
No work would be done in the Dungeness refuge, where terns were first seen nesting in 2003.
After the work is done on other sites — basically, developing bare stretches of sand — vegetation would be allowed to grow back on East Sand Island, near the mouth of the Columbia River.
That would shrink the available nesting area there.
The idea is that the birds would look for new nesting areas as conditions on the island become more crowded.
“We are hoping that some will find their way up there,” said Joan Jewett, chief of public affairs for Fish and Wildlife’s Pacific region.
About 9,175 nesting pairs of the terns currently use East Sand Island, representing about 70 percent of the West Coast population.
77 sites considered
That level of concentration leaves the birds vulnerable to devastation from disease or a storm, so biologists looked for ways to spread the population.
They considered 77 sites up and down the Pacific Coast, many of which already had terns.
The list was winnowed until it included the Dungeness refuge; Fern Ridge Reservoir, Summer Lake and Crum Lake in Oregon; and Brooks Island, Don Edwards National Wildlife Refuge and Hayward Regional Shoreline in San Francisco Bay.
The plan was put together by the U.S. Fish and Wildlife Service, the Army Corps of Engineers and the National Marine Fisheries Service.