Polar bear cubs face extraordinary survival challenges as climate change reduces sea ice and shortens the fasting period for nursing mothers. Cub welfare is among the most climate-sensitive wildlife welfare issues.
Polar bear cub welfare is directly affected by maternal nutritional status, which is determined by sea ice availability. Mothers who cannot build sufficient fat reserves before denning produce lower-quality milk, raising smaller, weaker cubs with reduced survival rates. Cubs that emerge from dens in poor condition face the additional challenge of a shortened sea ice season providing insufficient time to learn hunting before their first summer fast. Climate change thus creates a compounding welfare harm: weaker cubs entering a more challenging environment. Supporting climate policy that limits warming to the lowest possible trajectory directly serves polar bear cub welfare across a multi-decade timescale.