How deer survive the winter

When walking through deep snow, it's always easier when someone else leads. That person gets tired breaking the trail, but everyone who walks in his or her footsteps has an easier time of it.

That is one reason that deer congregate during the winter. When they all use the same network of trails through the snow, they have to utilize less precious energy tromping through deep areas than they would if they were by themselves.

White-tail deer are exceptional at surviving cold temperatures and brutal winter seasons throughout their range. Here are some ways they do it:

Deer hair helps keep them warm and toasty.

Human body temperature is about 98-99 degrees, whereas a white-tail deer temperature is 104. Their red, summer hair is solid and doesn't have an undercoat, helping them stay cool in warm temperatures, and they shed that hair and grow a new winter coat that helps them stay warm during cold temperatures.

A deer's winter coat has hollow guard hairs over a furry undercoat that helps keep its body heat inside. Deer are so insulated that their body heat doesn't even escape enough to melt the snow on their backs, so they don't feel the cold from the snow. They even have special muscles to help them adjust the angle of their hair for maximum insulation.

In addition, the color of deer change from a reddish-brown to a gray-brown in the winter, because the darker color helps them to absorb more of the sun's heat to warm themselves even more.

They bulk up.

To survive on less food during winter, deer will stock up on fat stores by eating throughout the fall. A deer with enough fat stores can lose up to 30 percent of its body weight and still survive.

white-tail deer

White-tail deer scrounge for seeds in the avian courtyard at the Dickinson County Nature Center.

You won't see deer moving as much.

To preserve their fat stores and energy reserves, white-tail deer slow down during the winter. They tend to move more during daylight hours when temperatures are warmer and bed down at night to conserve energy when temperatures drop.

They look for "deer yards."

Special areas that have perfect conditions for winter survival, called "deer yards," have trees that protect them from the elements and trap heat, have food sources and have nearby southern-facing slopes where they can absorb the sun's heat on sunny days.

Deer congregate in the winter.

In addition to helping break trail for each other, deer congregate in the winter for a variety of reasons. They can all access food and cover, and it also helps them to escape predators. When there are more deer, each one has a higher likelihood of not being eaten by a coyote or other predator.

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