Polar bears (Ursus maritimus) are uniquely dependent on sea ice for hunting seals, and accelerating Arctic warming is creating chronic nutritional stress and welfare deterioration across much of their range.
Polar bears experiencing extended ice-free seasons face progressive nutritional stress as they burn fat reserves without ability to replenish them through seal hunting. Body condition scores — measurable from photographs — have declined significantly in some subpopulations. Bears in poor body condition have lower reproductive success, higher cub mortality, and are more likely to enter human settlements in search of food. The chronic stress of inadequate nutrition across extended periods constitutes genuine welfare harm at the population scale. Individual bears encountered near communities are sometimes killed for human safety — a welfare cost that would not arise without climate-driven habitat loss. Addressing polar bear welfare at the root level requires addressing climate change — no other intervention can substitute for sea ice restoration.