evidence: In Davis Strait, for example, both the extent and thickness of the sea ice have been declining dramatically. In theory, this should be trouble for the local bears, which, like polar bears everywhere else, rely on solid sea ice as a hunting platform. Yet this population is an eye-popping 233 percent bigger than it was four decades ago. It’s tempting to simply declare victory and walk away. And yet this new-found abundance is entirely the result of local management practices that originally had nothing to do with bears. Specifically, in 1983, the European Economic Community banned the importation of the hides of whitecoat harp seal pups. In most places, the polar bear diet consists primarily of ringed or bearded seals. But polar bears aren’t picky eaters; when harp seal populations exploded, polar bears gorged. On the other hand, one theory holds that the loss of sea ice could encourage killer whales to move into polar bear habitat, snatching up all the seals and becoming the new dominant marine mammal.