Tuesday, June 01, 2010

Fish invaders causing dramatic downturn in birds

Biologist Linda Beck stands in water halfway to her knees, gazing out on a lake strangely empty of waterfowl. Cormorants, pelicans, gulls and terns by the millions once wheeled and shrieked above Malheur Lake while ducks bobbed and dove for insects. Now, the lake and sky are eerily empty. "I mean, there are no birds," said the 35-year-old fish biologist for the U.S. Fish and Wildlife Service, splashing to dry ground on the north shore on a recent afternoon. "We still should be seeing some birds." There's a one-word explanation for the dramatic downturn in waterfowl on the shallow 50,000-acre lake 30 miles south of Burns: carp. Their ranks have exploded over the course of decades -- and nothing, not even a succession of wholesale poisonings, has beaten them back for long. Carp out-compete the waterfowl for Sago Pondweed, aquatic invertebrates, insects and other food. They also root on the lake bottom, stirring up sediment and diminishing the sunlight necessary for the growth of lake grasses. "It's a giant carp pond," said Bob Sallinger , spokesman for the Audubon Society of Portland. "That lake is basically a dead lake."...more

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