Do polar bears hibernate?
Polar bears do not hibernate in the true sense of the word. True hibernators experience a marked drop in heart rate and a body temperature that plunges to nearly 0 C (32 F). Polar bears do not enter a state of deep hibernation; instead they undergo “walking hibernation.” Only pregnant female bears enter a den. They do so in the fall and give birth to their cubs in November or December. The bear family will remain in the den until March or April.
Female polar bears (sows) do lightly hibernate when they are pregnant. Only pregnant sows hibernate, because they need to save their energy while they wait to give birth. While the other polar bears may start to hunt out on the ice in October or November, sows head inland to a den to rest until they give birth in about January. Something not often considered with polar bears is that they are on a very different cycle than other bears. While a black bear eats all spring, summer and fall, then hibernates in the lean winter months, polar bears have the opposite schedule. Polar bears, hunt seals out on the ice, so they need cold temperatures – winter is feast time, and summer is the lean time of year to live off their fat.
Polar bears do not hibernate in the true sense of the word. True hibernators experience a marked drop in heart rate and a body temperature that plunges to nearly 0° C (32° F). Polar bears do not enter a state of deep hibernation; instead they undergo “walking hibernation.” Only pregnant female bears enter a den. They do so in the fall and give birth to their cubs in November or December. The bear family will remain in the den until March or April.
