Brrr…the temperature is dipping and snow is falling. Wildlife around us are preparing for winter. Certain species of birds flock together in the fall to prepare for great flyway migrations to the south where the weather is warmer and food sources are available. As the flocks fly overhead, a number of other animals prepare to spend winter in Ohio.

Winter birds in Ohio, such as dark-eyed juncos and white-throated sparrows, mingle with year-round residents blue jays, cardinals and chickadees. Fuel efficiency is the name of the game! With small external appendages such as ears and legs, radiating heat is kept to a minimum. Many birds have an antifreeze adaptation known as a counter current heat exchange system in which the arteries and the veins in the feet and legs run side by side, allowing cold returning blood in the veins to be warmed by the arteries. Feathers help conserve heat and keep exposed skin to a minimum.

Winter birds eat food rich in energy such as seeds, fruit, nectar and rodents. All of these foods produce higher levels of metabolism and subsequently more production. Chickadees eat 20 times more food in winter than summer. At certain temperatures, chickadees stop looking for food because the energy expended to find it is greater than the energy obtained from the food they find. Behaviors such as huddling together to say warm and foraging in bands to learn of new food sources help birds survive the winter. Don’t’ forget to help out by stocking your birdfeeder and providing a source of water!

Some mammals, such as white-tailed deer and squirrels, remain active all winter. White-tailed deer browse on woody plants and can be found in sheltered forests. Squirrels get ready for winter by building caches of nuts and seeds in the fall. Fox squirrels are seen hiding individual nuts, while red squirrels hide all of their food in one location. 

What happens to the animals that we don’t see as frequently in winter? These animals eat heartily during the fall to build up their fat reserves, preparing them for either a state of torpidity or hibernation. 

Some animals enter a state of torpidity, which is controlled hypothermia. Their body temperatures drop and the heartbeat slows down; thus the animals need less food to stay alive. Yet, these animals are easily awakened. Skunks, raccoons and opossums sleep during the coldest parts of winter but awaken to look for food when there is a break in the weather. Utilizing other animal’s burrows, holes in trees and possibly your garage, these animals find a warm home to wile away winter. Chipmunks build deep burrows below the frost line with several chambers, including a bedroom, storerooms for food and an indoor toilet! Their home is set up so they never have to venture into the cold until spring arrives.

The last group of animals are true hibernators. They sleep soundly and are hard to wake up. Their body temperatures drop to near freezing. The only true mammalian hibernators in Ohio are jumping mice, groundhogs and little brown bats. In fall, groundhogs eat lots of food to store fat, and then they burrow under the ground below the frost line where they sleep as long as six months until spring arrives. Little brown bats hibernate in caves, bell towers and even your attic until spring. Reptiles and amphibians, which are cold-blooded animals, dig deep into the mud under ponds and streams, or leaf litter and soil to spend winter. They literally “freeze.” A chemical in their blood keeps ice crystals from forming and damaging their cells. 

Winter may appear to be a quiet time, but complex systems are at work. Wild animals in Ohio spend the winter in a variety of ways. Although they may not be visible, they are still an integral part of nature for all to enjoy and appreciate.