Winter survival in Montana

We turn up the heat, put on a sweater, plug in the car. They leave town, go to sleep or tough it out. They are wildlife, specifically Montana’s wildlife that have to deal with the rigors of our winter.

Speaking of winter, if you have lived here a long time and still complained about December’s cold snap, consider yourself spoiled. I know I am.

While we can adapt to winter’s overdue cold spells, wild animals have three basic strategies for dealing with winter, and they are the same each year, no matter the weather.

Birds that spend their winters here, for example, do not suddenly decide to head to Mexico because the recent cold snap was the worst in 15 years, though you and I might.

Elk, deer or even a mink that tough out every single winter of their existence cannot flip a coin and make a choice to hibernate.

Wild animals over eons of time have carved their natural niche and it works. Not for all animals, all the time. Some of those critters that hibernate don’t make it until spring, or they wake up and there’s not enough to eat and they starve. Some of the birds that migrate, get lost, picked off by predators, fly into buildings and die.

What I find fascinating are the ways wildlife that stays here and stays awake deals with winter. Geese or ducks will stand or sit for hours on an ice shelf next to a river’s open water. Of course, they carry a nice plump down coat. But what about their exposed feet?

First, their legs and feet have very little soft tissue. Even the muscles that operate the foot are mostly higher up in the leg and connected to the bones of the feet with long tendons. Lack of soft tissue means less need for warm blood.

Second, warm blood flowing through the birds’ arteries passes close to cold venous blood returning from the feet. As arterial blood warms up the venous blood, the feet are kept cool, and the few tissues in the feet are supplied with just enough warmth to avoid frostbite.

Mammals, like elk, have thick fur coats we can only dream about. An elk’s winter coat has two layers — a dense, woolly undercoat covered with thick, long guard hairs.

Each guard hair contains thousands of tiny air pockets, making it waterproof and providing insulation. In very cold weather, snow on the thick guard hair coat often doesn’t even melt because the animal’s body heat is held in by the undercoat. Also, elk can make their hair stand on end, creating a thicker coat that traps more air.

As a final trick, when deep snow and bitter cold become major problems for elk, they will either gather in tight groups on windswept areas to take advantage of warmth and safety in numbers, or move into conifers, seeking insulation.

Whatever it takes, those animals that spend their winters here awake have evolved some amazing strategies to survive. We should be so lucky.

Bruce Auchly is the Montana Fish, Wildlife and Parks Region 4 information officer.