Polar bears are the planet’s biggest land-based carnivores – although they actually spend most of their lives around water and ice (their Latin name means ‘sea bear’). So they’re at particular risk from global warming, which is melting the Arctic sea ice they depend on.

Polar bears generally live and hunt alone, though they can be quite social too. They mainly eat seals – using their remarkable sense of smell they can detect a seal in the water beneath a metre of compacted snow, and from almost a kilometre away.

Adults are strong swimmers – they can swim for several hours to get from one piece of ice to another. Their thick white coat and a layer of fat keep them warm and camouflaged in their harsh Arctic environment.

It’s hard to imagine such impressive, powerful predators being vulnerable, but man-made climate change is making life tough for them – so their fate could be in our hands. We mustn’t let them down.