A Snowy Blizzard from the Far North

Fueled by global warming in its Arctic nesting grounds, an exploding population of lesser snow geese is causing big problems for farmers in Washington State

• Phil McKenna
• Feb 01, 2008

LAST FEBRUARY, birders from across the Northwest flocked to the small town of Stanwood, Washington, for the area’s second annual Snow Goose Festival. Created to boost the local economy, it included a pancake breakfast, bird-watching tours, wine tasting and live music from a local bluegrass band.

For festival organizer Laura Byers, the big attraction is the sheer number of lesser snow geese that come to call at Stanwood—a number that has skyrocketed in recent years. “The fields are white with them,” she says. Goose numbers are expected to be bigger than ever this year. But the booming population is not universally welcome and may be the result of an even bigger problem: global warming.

The invasion has prompted local farmers to declare war on the birds. “They’re like locusts,” says Ted Oien, whose dairy farm is located just two miles from the festival grounds. “They devour everything in sight.” Oien reckons the birds ate more than $12,000 worth of grass off his fields over the last two winters and figures they’ll continue to feast this year. “It’s hard to run a dairy operation when you don’t have grass to feed your cows.”

While lesser snow geese have been a familiar sight in Washington for some time, the number of the birds visiting each winter has doubled to 83,000 in just 10 years. Mike Davison, a biologist with the state’s Department of Fish and Wildlife, says the increase is due to climate change on a distant, windswept island in the Arctic Ocean. “Whether you call it global warming or a moderation in temperatures in a specific geographic area, it has caused these birds to be very successful in nesting,” he says.

The subpopulation of lesser snow geese that winters in the fields around Stanwood each year breeds primarily on Wrangel Island off the northeast coast of Siberia. The birds can only breed in large numbers if Wrangel’s winter snowpack melts early enough, which historically occurred about once every four years. But now, says Davison, “they have been getting access consecutively for six years.”

Wrangel Island, notes Russian biologist Vasily Baranyuk, “is getting warmer, no question about it.” Baranyuk has spent every summer, from May through September, on the island for the past 26 years. “Last summer, the mosquitoes were eating us alive,” he says. “Before, there were hardly any; it used to be too cold.”

A weather station on Wrangel, in operation since 1928, recorded a mean annual temperature increase of 2 degrees between 1970 and 2005. A similar warming trend occurred on the island in the 1930s and 1940s, suggesting cyclical weather patterns may affect Wrangel to some extent. However, the prior temperature increase was not as large or long lasting. And the current warming trend is consistent with average temperature changes throughout the Arctic. In general, says Baranyuk, the snowpack now melts and the breeding territory opens up about five or six days earlier than in the 1970s.

In such an unforgiving climate, a week or so can make all the difference. “The timing of Arctic nesting at those latitudes is really tight. The geese need to arrive, find nesting sites, lay their clutch of eggs and have time for the goslings to be on the wing before winter weather conditions return again,” says Tim Moser, a U.S. Fish and Wildlife Service biologist based in Minnesota.

Biologists in Washington anticipate 5,000 more geese this winter than last year and are expanding efforts to try to reduce damage caused by the escalating population. Last winter, the Washington State Department of Fish and Wildlife paid several farmers to plant nearly 1,000 acres of winter wheat and rye to lure birds away from other farms. They also organized goose hunts on the seeded fields. This year, they are extending the hunts by two weeks.

Changes in the birds’ migration patterns may be adding to the influx of the geese in Washington. Forty years ago, most of the geese from Wrangel Island wintered in California. Sightings in Stanwood were rare. But as foraging habitat deteriorated farther south, more and more of the birds started wintering in the Pacific Northwest. And the shift hasn’t been limited just to snow geese.

“We’ve seen populations of Canada geese shifting farther north all across the country,” says Moser. “This is largely due to a massive increase in agriculture since the 1950s.” In the case of the Wrangel Island snow geese, he adds, “it could be a combination of changes in land use and a warming climate.”

Oien and other local farmers don’t care what has caused the boom; they just want the geese to go away. But if Davison and Moser are right, an unexpected consequence of global warming may come home to roost every winter in Washington.

Writer Phil McKenna is based in Cambridge, Massachusetts.

Growing Dilemma

According to Canadian authorities, the overall lesser snow goose population is now growing at a rate of 5 percent annually. Throughout the bird’s range, the number of breeding pairs now exceeds 4.5 million—three times the amount counted two decades ago.