EAST SAND ISLAND, Oregon—Alexa Piggott is crawling through a dark, dusty, narrow tunnel on this 62-acre island at the mouth of the Columbia River. On the ground above her head sit thousands of seabirds. Piggott, a crew leader with Bird Research Northwest, is headed for an observation blind from which she'll be able to count them.


It's September, and the low-lying island is relatively quiet. Most of the fledglings and their parents have left, and only a few thousand pelicans and cormorants remain. But in the spring, 60,000 birds come here to nest. East Sand Island is home to the largest breeding colony of Caspian terns in the world and the largest colony of double-crested cormorants in North America—nearly 15,000 pairs.


That's too many cormorants, says the U.S. government. Starting next spring, it proposes to shoot more than half of the iridescent black birds, on the grounds that they're eating too many fish.


The cormorants eat mostly anchovies—but they also dispatch as many as 20 million salmon and steelhead trout smolts every year. The nesting season of double-crested cormorants on East Sand happens to overlap with the migration of the juvenile fish down the Columbia to the Pacific.


"They're eating over 6 percent of all the wild steelhead that are passing through the lower Columbia River," says Ritchie Graves, a fisheries biologist with the National Oceanic and Atmospheric Administration. They also consume more than 2 percent of the yearling chinook salmon.


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