As snow falls, it’s easy to wonder how creatures that live outside survive when bombarded with so much precipitation.

Adaptation truly is a wonder of science; all living things, by nature, do what they must do to stay alive. Humans wear warm clothes, stay within the comfortable confines of our homes, or sometimes escape to the warmer climates in the south. Similarly, mammals grow thicker winter coats, cozy dens are constructed, and songbirds fly to their neotropical winter homes.

Fattening up, hibernating, and migrating are all well-known winter survival tactics for wild animals. Yet, there is much more to hibernation than just going to sleep for a long time and more to “fattening up” than just eating lots of food. To look closely at these two winter survival methods is to better understand how the animals living in our very own Maine backyards prepare for the cold, snowy season.

With the arrival of colder temperatures comes the need for warmth. As animals begin to eat more, their bodies store the excess fat underneath their skin and around their organs. This fat does the same thing for the wild animals as a winter jacket does for us. But our winter jackets don’t offer us sustenance. Because winter weather reduces the availability of food for the animals living in our woods, wild animals utilize their fat stores for nourishment. Raccoons and deer, although hefty in size at the beginning of winter, are often slimmest when spring arrives.

At sub-freezing temperatures and signaled by diminishing daylight, an animal may seek shelter and enter a state of torpidity, meaning its metabolism slows down. In this state, less oxygen is needed for body function and body temperature can decrease to the minimum needed for survival. In the case of a woodchuck, body temperature can be as low as 6 degrees above freezing, with its heart beating just four to five times in a minute.

Slowing things down like this is a hibernating animal’s way of reserving its energy throughout the winter. When torpid, an animal looks to be sleeping, but it’s actually just a quiet, calm state of being. Woodchucks, field mice, and chipmunks are true hibernators, meaning that when hibernating, they are nearly unresponsive to what happens in nature around them.

Surprisingly, bears are not; bears enter a torpid state, but do not hibernate, as they can be aroused from their winter slumber, particularly females who give birth during the cold months.

It couldn’t hurt for humans to “walk on the wild side” a little bit and learn a thing or two from our outdoorsy friends. Once the temperature drops below 25 degrees Fahrenheit, raccoons will find a place to hibernate together. Doesn’t good company always help during cold and stormy times? So, enjoy good food and being warm with good friends, and remember – spring is just around the corner!

Megh Rounds is an environmental educator at the Portland Water District. She can be reached at mrounds@pwd.org.