Polar bears run riot as ice melts

By Shanta Barley You can almost hear Sarah Palin cocking her rifle. As climate change causes sea ice to shrink, the number of “problem” polar bears appears to be increasing. “Hungry bears don’t just lie down – they go looking for an alternate food source,” says zoologist Ian Stirling at the University of Alberta in Edmonton, Canada. “In many cases this brings them into human settlements and hunting camps.” Stirling’s team found that around the town of Churchill on the shores of Hudson Bay – the “polar bear capital of the world” – the number of bears reported as attacking humans, homes and hunting camps more than tripled between 1970 and 2005, from 20 to 90 per year. The shorter the sea ice season, the greater the reports of problem bear activity. This increase in problem bears comes despite a 22 per cent decline in the west Hudson Bay polar bear population since the late 1980s. Sea ice in Hudson Bay now melts three weeks earlier than it did in the 1970s. This has reduced the time polar bears have to hunt seals and build up sufficient fat reserves to survive the ice-free summer months without food, driving them to look for food in towns. Many of the problem bears were young males, which need the most energy.” …