6 surprising animals that hibernate

When we think of hibernation, bears and bats are usually the first animals that come to mind. But the natural world has many less obvious winter survivors. Some animals dramatically lower their metabolism and body temperature, while others enter related states of dormancy to survive months of cold and scarce food. (wikimedia commons)

Arctic Ground Squirrel: The Arctic ground squirrel is an extraordinary hibernator, spending around seven to eight months in hibernation. Its body temperature can plunge to about 27°F (-3°C), briefly dropping below freezing before the animal periodically wakes to warm itself. (wikimedia commons)

Box Turtle: The woodland box turtle doesn't technically hibernate—it brumates, the reptilian equivalent of winter dormancy. From around October until spring in colder parts of its range, it burrows into soil and drastically slows its metabolism, relying on stored energy while temperatures remain low. (wikimedia commons)

Dormouse: The dormouse is another small mammal that survives winter by entering prolonged dormancy. Rather than remaining active when food becomes scarce, it retreats to a sheltered nest and dramatically reduces its metabolism, allowing its stored energy reserves to carry it through the cold season. (wikimedia commons)

Little Brown Bat: The little brown bat can spend more than six months hibernating while waiting for insects to return. During deep torpor, its heart rate can fall from roughly 200–300 beats per minute to around 10, while its body temperature drops close to the surrounding temperature. (wikimedia commons)

Marmot: The yellow-bellied marmot is a true hibernator that can remain inactive for months. During hibernation, its metabolism slows dramatically and its body temperature can fall to around 37°F (3°C), while its heart rate can drop to fewer than five beats per minute. (wikimedia commons)

Wood Frog: The wood frog has one of nature's strangest winter strategies. It can allow much of its body to freeze solid, with its heart stopping and breathing ceasing. Special substances in its body act like antifreeze, protecting its cells until spring temperatures allow it to thaw and become active again. (wikimedia commons)