Polar bears are increasingly stressed by sea ice loss, forcing longer fasting periods, reduced hunting success, and nutritional decline across their range.
Sea ice loss is causing a slow-motion welfare deterioration for polar bears across their range. Extended fasting — beyond the physiological norm — progressively depletes fat reserves and forces catabolism of muscle protein. Bears in this state show reduced activity, impaired immune function, and reduced reproductive success. Cubs born to nutritionally compromised mothers have reduced birth weight and survival rates. Starvation is not a rapid or peaceful death — polar bears in late-stage nutritional collapse show lethargy, weakness, and progressive organ failure over days to weeks. Each year of additional ice loss extends the fasting period and worsens the aggregate welfare outcome for the entire population.