Wednesday, September 7, 2011

Human (Best Intentions) Intervention in Nature | Fails Again | Seattle Times

Trouble in seabird paradise

A government effort to save Columbia River salmon becomes an unexpected bird battle, forcing scientists to consider a flock of new questions and options after nature shows its unpredictable side.
Seattle Times environment reporter

EAST SAND ISLAND, Columbia River — It's been a dozen years since the federal government moved thousands of black-capped squawking seabirds here to reduce their diet of endangered fish.

Things haven't exactly gone as planned.

The hope in relocating the world's largest colony of Caspian terns to this sandy mound near the river's mouth was that they'd eat more sardines and herring — and fewer young salmon and steelhead. And they have.  

Thousands of these double-crested cormorants have settled on East Sand Island in the Columbia River, helping to turn what was supposed to be a peaceful home to a large, relocated colony of Caspian terns into a salmon-gobbling war zone of sorts in the battle to protect threatened fish.

But the move came at a price. This year the birds' summer retreat was transformed into a place of violence. A strange chain reaction involving divebombing eagles and marauding gulls kept this colony from producing a single chick.Cormorants on the Columbia River

Yet even with this bizarre turn the actual number of threatened fish slurped by birds is higher now than it's ever been. That's because this same desolate scratch of ground in recent years has also become home to the West Coast's largest gathering of double-crested cormorants.

Play video now

No comments: