Bear-spotting radar tracks polar bears migrating to the Arctic sea ice

Along the frosty coast of Hudson Bay, hundreds of polar bears have been wandering for weeks, waiting for the wintertime sea ice to form so they can return to hunting ringed seals. Until then, they represent a danger to the 900 people living in nearby Churchill - a remote, sub-Arctic town in Canada famous for the visiting carnivores. The town is working on a plan to prevent conflicts between hungry bears and humans, using a new radar system that can watch and warn when a bear approaches and do so in a snowstorm and during the dead of night.