Polar bears are at risk of starvation in longer ice-free seasons in the Arctic, despite their ability to adapt their diet and behaviour, scientists have warned. Climate change is increasing the time some areas of the Arctic are ice-free each year, forcing polar bears– which are specialised to use the ice to hunt their preferred food of seals – to spend longer on land in those regions. Polar bears monitored by scientists in a new study led by researchers from Washington State University, tried different strategies to maintain energy reserves on land, including resting, scavenging and foraging, but almost all lost weight rapidly.