Nature’s Winter Game Plan

How Animals Prepare - and How You Can Help

Photo By Theresa Ray

As we enter the season of Fall, we start to think of the coming winter and how we can prepare ourselves, our homes, and our yards for the cold and snow. We are not alone in this. Many species of insects, mammals, reptiles, and amphibians are also preparing for the colder months, right alongside us. During the fall, there are a variety of steps that we can take to make the area around us more hospitable for such wildlife. By doing so, we can help all of these species to be ready to survive the cold when it comes.

In order to help animals survive the winter, it is important to understand how different species adapt to the cold weather. There are lots of different, fascinating strategies used throughout the animal kingdom. One that you may already be familiar with is hibernation, a strategy used by certain species of mammals to sleep through the entire winter. These animals spend their time in the fall gathering food to store fat in their bodies, which they can live off of as they rest. They also seek out a shelter, called a hibernaculum, to sleep in during the winter. Once hibernation begins, the animal will essentially enter a coma, and remain asleep in its shelter until the spring. 

Although hibernation is perhaps the most well-known way that mammals deal with winter, it is in fact not the most common. Here in Michigan, only a few species actually hibernate, such as chipmunks, groundhogs, the thirteen-lined ground squirrel, and several types of bats. Most other mammals do not hibernate during the winter, but rather go into a state of dormancy, where they spend most of their time asleep in their shelters. This may sound the same as hibernation, but there is a difference! When a true hibernator begins its long winter rest, it goes into such a deep sleep that it is very difficult to wake up. For most mammals, this is not the case. They instead enter a much lighter sleep, from which they may occasionally wake to eat or forage.

Groundhog & Chimpmunk, Photos By Theresa Ray

Other sorts of animals, like insects, have their own ways of dealing with winter. Among the most famous of these is the yearly migration of the monarch butterfly, which deals with the cold by simply moving South to warmer weather. While some insects migrate in this way, others prefer to overwinter in various life stages. Some insects, such as certain moths, will pupate throughout the winter, transitioning into their adult stage when spring comes. Other insects will simply bury themselves beneath leaf litter for cover from the snow.

Amphibians have their own strategies for lasting through the winter. In most cases, they enter a state of dormancy called brumation. This is very similar to hibernation in mammals, as the amphibians will spend the fall storing fat to survive, and then finding shelter to rest in. But unlike hibernation, amphibians may actually come out of brumation on particularly warm days. Some amphibians have a more odd strategy for surviving the cold: wood frogs actually freeze solid in the winter! While this would be fatal to most animals, wood frogs have a unique ability to use glucose to keep their cells from freezing. 

Wood frog, Photo by Courtney Celley/USFWS

Reptiles are similar to amphibians, in that many of them also go through the process of brumation. However, many reptiles take their own approaches to the long sleep. For example, turtles are actually able to brumate underwater. By absorbing oxygen through their cloacal opening, turtles can seek out their shelter in the deeper parts of ponds and wetlands. Snakes are another group of reptiles that often go through brumation, and unlike many other species, they tend to brumate in groups. In fact, garter snakes, a common species here in Michigan, can have hundreds or even thousands of individuals in their communal shelters.

With so many different ways that animals survive the winter, there are also lots of ways that we can help them to do so. Perhaps the most important thing that we can do is to leave the leaves alone. When leaves fall and pile up on the ground, they become an excellent shelter for many insects, amphibians, reptiles, and other small foragers. Many of us will undoubtedly want to clean the leaves off of our lawns, which is understandable, but making a space to leave them alone can go a long way in helping a wide variety of animals make it through the cold months. Other types of shelter can also be helpful to wildlife, such as leaving downed logs in place, or even providing things like bird boxes. 

Blue Heron Headwaters Nest Watch Program.

Another way you can support animals in the winter is to help provide water. Water

that is drinkable is tough to come by for some species during freezing temperatures. Keeping liquid water in a birdbath or pond can be very helpful for any species that remain active in the winter. Furthermore, you can also help certain species by making sure your gardens and yards include winter plants. Some plants stay active and even bloom during the winter, including many evergreen trees. These can provide a great source of food and shelter to foraging wildlife, especially birds, when other sources are scarce. It can be even better to include species that are native to Michigan. Juniper berries and Michigan Holly are a couple of native species that can be of great help to overwintering birds. Now is a great time to plant winter-bloomers, as they will be able to establish roots over the fall.

The next most important thing that we can do for wildlife over the winter: leave them be! The cold months are hard for wildlife, and they need all the energy they have to survive. When we disturb resting wildlife, it puts strain on the precious few resources that they’ve stored up, and can put them at risk of starvation. So if you do come across the shelter of a dormant animal, remember to keep your distance from it and let the animal rest. 

As fall begins, now is the time to start making preparations! By following these strategies, we can make our lands a better and safer place for wildlife as they slumber through the cold Winter months.

Photos By Theresa Ray, John Meyland & Silent Light Photography