The polar bear (Ursus maritimus) has become the iconic symbol of climate change, and with good reason — its welfare is directly and measurably linked to Arctic sea ice extent. Hudson Bay polar bears are experiencing earlier ice breakup and later freeze-up, extending their ice-free fasting season and causing progressive population decline.
Polar bears experiencing extended fasting periods suffer progressive nutritional stress: initially mobilising fat reserves, then breaking down muscle protein in severe cases. Malnourished females produce less milk for cubs, causing cub growth failure and mortality. Bear-human conflict increases as food-stressed bears enter communities seeking food, resulting in bear mortality through conflict resolution. Climate-driven reproductive failure — females too thin to reproduce successfully — compounds population welfare decline across generations. Captive polar bears in zoos designed for northern climates face welfare challenges from summer heat that are increasingly problematic as temperatures rise.