Student Article

Imagine being able to sleep through the entire winter or nap during a super hot summer! That’s what some animals do to survive tough weather.

Hibernation: how animals sleep through the cold

When the weather gets too cold , some animals sleep to save energy when food is hard to find. Hibernation is when animals slow down their bodies to survive cold winters. Their heart beats slower, and they breathe less often. Some animals, like bats, hibernate in cozy dens or caves. Others, like frogs, burrow under mud.

Hot weather sleep: aestivation

Animals in hot places do something similar called aestivation. This helps them survive dry, hot weather. Snails, frogs, and some reptiles hide in cool, damp spots to keep from drying out.

Torpor: brief energy breaks

Some animals take short, daily naps called torpor. Hummingbirds and bats use torpor when it’s chilly. They sleep lightly but can wake up quickly.

Denning: light sleep for bears

Bears do something a little different called denning. They sleep lightly through the winter but can wake up easily. Amazingly, mama bears even give birth while they are still in their dens!

How do animals prepare to hibernate?

Animals hibernate or aestivate to survive when food is scarce or the weather is rough. They store fat in their bodies before sleeping to give them energy.

The risks of hibernation

Hibernation is not always safe. Animals can be attacked by predators or run out of fat. Warmer weather caused by climate change can also confuse animals, waking them too early.

Fun fact!

The common poorwill bird is the only bird known to hibernate! It hides in rocks during cold weather.

© Dominic Couzens / Our Media