Polar bears are among the most climate-vulnerable large mammals on Earth. Their dependence on sea ice for hunting makes them a frontline indicator of Arctic ecosystem collapse driven by warming.
Polar bear welfare is inextricably linked to sea ice conditions, making climate change the dominant welfare threat. Extended ice-free seasons — now 3-4 months in some areas compared to 2-3 months historically — force bears to fast for longer, depleting fat reserves needed for reproduction and survival. Female bears in poor body condition produce fewer cubs and have lower cub survival. Emaciation is documented in bears unable to access sufficient seal prey. In areas where bears are forced into human communities searching for food, conflict leads to bears being killed or relocated — stressful and often fatal management interventions. Research documents stress hormone elevations in bears experiencing prolonged fasting. In zoos, polar bears require very large, complex environments — their vast wild territory makes truly adequate captive housing essentially impossible.