in the Arctic. The polar bear is the only species of bear that is a
marine mammal, meaning one that completely depends on the
ocean for food and habitat. These enormous bears—males can
weigh nearly 1,000 pounds (454 kg)—spend most of their time on
Arctic sea ice, where they hunt for food. Their diet consists almost
exclusively of calorie-rich ringed seals. In areas where there is no
sea ice during the summer months, like Hudson Bay, Canada,
polar bears live on land until the water freezes over again in the
The effects of climate change are
most stark in the Arctic, where
rapidly melting ice threatens the
survival of polar bears. As ice
melts, polar bears must swim
across larger stretches of open
water in search of food.
