Tormenting terns to save salmon

Caspian terns nesting on Rice Island last year

April 7, 2000
Web posted at: 11:37 AM EDT (1537 GMT)

In this story: A living conveyor belt Byproduct of human tampering? Enter the tern-inator RELATED STORIES, SITES

By Correspondent Jack Hamann

HELP WANTED: LIVE AND WORK ON A DESERT ISLAND. CHASE BIRDS. BATTLE SUN AND WIND BY DAY, RAIN AND COLD BY NIGHT. ABILITY TO TOLERATE LONG STRETCHES OF SOLITUDE A PLUS.

RICE ISLAND, Oregon (CNN) -- Sound like the job for you? Sorry, it's already been filled.

For 82 days, spanning spring and summer, six hardy men will rotate round-the-clock shifts on Rice Island, a remote pile of sand and brush near the mouth of the Columbia River. Their sole duty? To chase birds.

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The birds are Caspian terns, sleek seabirds with white bodies, black heads and perhaps the most grating, obnoxious squawk you've ever heard. If the world's songbirds were a symphony orchestra, Caspian terns would be in the audience, blowing their noses.

Caspian terns are found throughout the world, not just around the southern Russian sea that gives them their name. A sizeable number spend their winters in Mexico and Guatemala, then fly north to nest in the Pacific Northwest. Over the past decade, they've fallen in love with one spot in particular: Rice Island, where gourmet meals are cheap and plentiful.

Rice Island is a giant artificial sand pile near the mouth of the Columbia River

The main entrée, of course, is salmon: millions of salmon smolts (fingerlings) winding their way to the Pacific Ocean each year from the fresh waters of the sprawling Columbia River basin. Twenty miles upriver from the mouth of Columbia, where salt water begins to mix with fresh, the salmon smolts slow down to get their bearings. To the Caspian terns' delight, Rice Island is plunked smack in the middle of Slow Salmon Central.

Back when Lewis and Clark paddled past this very stretch of river, the Columbia teemed with hundreds of millions of wild salmon. Those amazing fish functioned like a giant conveyor belt, getting fat in the Pacific and then transferring tons of rich nutrients from the ocean to streams high in the mountains. Birds, bears, trees and people -- some as far as 1,000 miles inland -- all benefited mightily from these incredible animals.

But these days, 14 of the 17 wild runs of salmon (and their cousins, the Steelhead trout) are listed as endangered. A string of giant dams brought cheap electricity, flood control, irrigation and low-risk transportation to a once-wild corner of America. But the dams turned the Columbia into a series of slow-moving reservoirs, making life miserable for baby salmon heading to the Pacific.

Which brings us back to terns. In 1997, Oregon State University scientists Carl Schreck and Larry Davis made an amazing discovery: The Caspian terns nesting on Rice Island were gobbling millions of salmon smolts every year. While billions of dollars were being spent or set aside to try to either modify or even breach upstream dams, one colony of migratory birds seemed to be doing as much damage as all the man-made obstructions combined.

Predictably, there was an uproar. Dam supporters demanded a halt to all dam removal discussions until something was done about the terns. Environmentalists countered that the numbers from the Oregon State study were being grossly exaggerated and that dams were still the main problem.

Bird biologists say terns are simply a predictable byproduct of the human tendency to over-engineer the environment. Rice Island is not natural: It's an artificial dumping ground for millions of tons of sand dredged each year from the Columbia River by the Army Corps of Engineers to help giant cargo ships navigate inland. At one point, the Corps and the U.S. Fish and Wildlife Service actually encouraged terns to nest on the island, figuring it was a good use of an otherwise barren chunk of land.

And even the fish themselves are a product of human engineering. These days, almost 90 percent of salmon in the Columbia were raised in hatcheries. Unlike their wild cousins, hatchery fish are notoriously inbred and sluggish, making them easy prey for a whole host of birds, sea mammals and larger fish throughout their lifelong migrations.

"It's one of my pet peeves," laments Oregon State University biologist Dan Roby. "Here we've set the table for the terns, and now we're complaining about them taking advantage of it. We've provided them with ideal nesting habitat, we've provided them with millions and millions of really dumb smolts. Now the chickens, so to speak, are coming home to roost."

Dan Roby, lead researcher for Caspian Tern Relocation Project

Roby is the lead researcher for the Caspian Tern Relocation Project. Last year, federal and state agencies paid to have Roby's team of biologists string thousands of yards of black tarp across prime Rice Island nesting area. Egg-laying terns demand bare sand and unobstructed views of the water, so the tarps seemed like a decent solution. At first, only 1,500 pairs dug nests on Rice Island. At the last minute, however, another 6,000 swooped in, creating a crowded tenement of terns all determined to make more baby birds. Once again, salmon were on the menu.

Caspian terns are not listed as an endangered species. Thanks to the plentiful meals around Rice Island, the colony has positively flourished, exceeding 10,000 nesting pairs in 1998. But killing the terns is not a legal option: They are protected under international treaty by the Migratory Bird Act.

So this year, they'll try again. As before, they are stringing tarp. And just like last year, they're hoping the terns will choose a better location. To that end, they are clearing nesting space on an island 17 miles closer to the Pacific, where the river meets the sea, and fish other than salmon are available. But this year, there will be a new weapon on Rice Island.

Forty-seven-year-old Michael K. Johnson (his friends call him "Michael K") owns a small tugboat company in Kelso, Washington. Johnson was the low bidder when the Army Corps of Engineers went looking for someone willing to live on Rice Island during the nesting season.

"I've never done anything like this before," Michael K says. "I asked a few of my friends if they'd be willing to try this with me, and they said, 'Why not?' So here I am."

Michael K is loading two campers on a barge, which he'll soon anchor off Rice Island. Working 24 hours each day, two-person shifts of mostly middle-aged men will experiment with anything short of shooting the birds.

In 1999, a fake eagle didn't fool terns. Will a fake village do the trick?

"We'll wave our arms, use kites and mirrors, anything we can think of," Johnson says. He's planning to construct a Northwest version of a Potemkin village: fake buildings, complete with scarecrows, that might trick terns into thinking their nesting ground is now a suburb.

The Army Corps of Engineers will fork over $62,000 for the experiment, and already Michael K is sure he'll lose money. He won't be allowed to harass terns if they somehow manage to lay their eggs, so the job will literally be a 24/7 commitment to keep them from building nests. If all goes well, Michael K thinks this could be the start of a new, albeit specialized career, since tern harassment will likely need to continue for years to come.

"We're gonna fight these bastards," promises Michael K, "and we're gonna win."

Millions of salmon smolt certainly hope so.

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US Army Corps of Engineers, Portland District Home
tidepool.org - Caspian Terns
Caspian Terns
Wildlife Information Scrapbook
Black Hills Audubon Society - Conservation

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