How Do Hibernating Animals Know When To
Wake Up?
Wake Up?
By CHRIS LITTLECHILD
History - Science
Hibernating animals are able to gradually lower their body temperature and the rate of their metabolism. However, there are different kinds of hibernation, as bears and other mammals only enter a state of torpor — a kind of hibernation-lite — unlike certain fish and cold-blooded animals.
During torpor, animals can wake quickly when sensing prey or a threat, as they usually would, and the effects on their bodies are less severe, but awakening from full hibernation typically requires a little help from the very power hibernating animals are sheltering from — nature itself. The warming weather that arrives with the spring rouses a lot of hibernators.
Lori Naumann from The Minnesota Department of Natural Resources says that for "some animals, it is temperature dependent and it's weather and daylight dependent, but other animals, it's hormonal." Ground squirrels are an example of creatures whose hibernation is governed by the thalamus, a structure in the center of the brain that routes the information gathered by our senses (though not smells) and sends it where it needs to go.