Polar bears face existential threats from sea ice loss driven by climate change, with welfare impacts cascading from food insecurity to reproductive failure and increased human conflict.
Climate change is causing progressive welfare deterioration for polar bears through the mechanism of habitat loss - sea ice that serves as their hunting platform is disappearing, causing food insecurity and nutritional stress during extended ice-free periods. Fasting periods that once lasted weeks now extend to months for some populations, depleting fat reserves needed for reproduction and survival. Nutritionally stressed females produce fewer cubs and have reduced milk quality, compounding population decline. Bears driven to garbage dumps and human settlements by hunger face conflict and lethal removal. The welfare trajectory for polar bears under continued high-emissions scenarios is one of progressive deterioration over coming decades, making climate action the most important single welfare intervention.