ASTORIA, Ore. – A plan to protect young salmon by killing double-crested cormorants on an island in the Columbia River has backfired after the birds fled the area halfway through their nesting season.
Two dead cormorants and 14 cracked eggs are the only recent evidence that the birds have tried to return to nesting grounds on East Sand Island since abandoning nests in May, The Daily Astorian reported.
This is the second time in two years that the birds have abandoned the island in the middle of their nesting season.
The Army Corps of Engineers kills the birds to reduce predation on runs of threatened and endangered juvenile salmon.
The Corps has put a hold on killing the birds until it is clear if the colony will re-establish itself on the island.
Last year, the agency’s contractors killed nearly 3,000 adult birds and destroyed 1,092 nests despite the birds leaving the island and returning at the end of June.
The Corps’ goal is to cut the island’s population of cormorants in half by 2018.
Conservation groups, however, believe the plan is harming the colony of birds.
“It’s very possible that the combination of eagle predation activity and lethal control activity being conducted by the federal agencies are acting in a cumulative manner to put pressure on this colony,” Bob Sallinger, conservation director for the Audubon Society of Portland, wrote in a letter to the U.S. Fish and Wildlife Service. “While the colony may have been able to withstand the pressure of eagles alone, the added impacts of pervasive shooting, egg oiling and other elevated human activities has significantly increased the scope, scale, frequency and intensity of threats to the cormorants.”
Subscribe to the Morning Review newsletter
Get the day’s top headlines delivered to your inbox every morning by subscribing to our newsletter.