On Thin Ice with Churchill's Polar Bears
The town of Churchill, Manitoba (population, at last count, 926), sits 600 miles below the boundary of the Arctic Circle, a speck of civilization in an otherwise vast expanse of tundra, boreal forest, and icy sea. The community’s small grid of streets—home to a few modest hotels and restaurants, a handful of Eskimo galleries, a market and post office, and not much else—has an economy based almost completely around polar bear tourism. It’s all about the location: Churchill hugs the western edge of Hudson Bay—a saltwater basin twice the size of Texas that empties into both the North Atlantic (to the east) and the Arctic Ocean (to the north). Each winter, when air temperatures plunge to around -25 degrees, the bay begins to freeze, its rolling wavelets hardening to wadded hummocks of ice.
It’s this freeze, which happens around mid-November, that brings the polar bears—some 1,000 of them, collectively known as the Western Hudson Bay population. Typically, these bears spend the warm months between July and November denning (and subsisting without food) in regions far to the south. But once it starts getting cold, they migrate, often walking hundreds of miles, to the main gateway to their winter feeding grounds: the Hudson Bay coast.
By the time they reach Churchill, most bears have lost between 20 and 30 percent of their early-summer body weight. Depleted and famished, they are desperate to reach the remote colonies of ringed seals that are their main food source. But the seals can be more than 100 miles out from shore—too far to swim, even for the powerfully water-optimized bears. To claim their feast, they have to walk to it—which means they first have to wait for the bay to ice over.
Their wait has been growing longer. Warmer temperatures mean that sea ice now forms in Hudson Bay almost a month later than it did 30 years ago, and the shortened seal-hunting season has taken a toll on both the bears’ weight (which has dropped by 15 percent) and the number of new cubs born (since mother bears have to maintain a healthy weight of at least 450 pounds to reproduce).
This explains why, for about four weeks each year starting in mid-October, the world’s largest concentration of polar bears can be seen massing along the Churchill headlands overlooking the bay, sniffing the air for the scent of hardening ice. The sight is an enormous thrill for travelers, who come by the thousands to see the bears from the safety of naturalist-guided vehicles. (Along with Natural Habitat Adventures, which has run tours in Churchill since 1989, several other outfitters have bases here.) But timing such a visit right is crucial; once the sea ice forms, the bears can disappear from Churchill in a matter of hours.