How Wildlife Survive Winter Extremes

By Scott Shalaway
THOUGH the recent cold and snow seem a distant memory, they prompted many interesting e-mails asking the same question: What happens to the wildlife in areas when the temperatures are frigid and huge amounts of snow fall in a matter of days?

The short answer is, not much. Most species are adapted to cope with winter weather. Many, including invertebrates, frogs, turtles, snakes and some mammals, simply shut down and enter a season-long torpor.

Two common aquatic mammals deal with winter much like we do, they build shelters. Muskrats and Beavers build lodges with underwater entrances. Even when their ponds freeze over and are covered with snow, they slip freely into the water to feed on aquatic vegetation (Muskrats) or the bark of limbs and branches (Beavers) they’ve stored under the ice.

Though Muskrats are limited to wetlands or stream banks with sufficient water to cover their den entrances, Beavers can manipulate their habitat by building dams to create ponds where food is available.

Throughout the year, myriad aquatic invertebrates, fish, frogs, turtles, snakes, waterfowl, wading birds, swamp sparrows, prothonotary warblers and mammals such as mink, otters and Raccoons enjoy the fruits of the Beaver’s engineering expertise.

Squirrels rarely are bothered by winter weather. They fatten up in the fall and store caches of food they use throughout the winter. On days when the thermometer barely climbs above zero, they wisely stay in their dens. I didn’t see any Fox Squirrels at my feeders recently until day time highs reached into the 20s.

Chipmunks and Flying Squirrels are much smaller than tree squirrels, so they lose body heat more rapidly than their larger kin. Chipmunks respond by hibernating. They simply spend the winter in subterranean burrows where they occasionally wake to eat some of the seeds they’ve stored in their underground retreats. Because Chipmunks wake periodically to eat, one can argue they are not true hibernators.

Flying Squirrels, like other tree squirrels, do not hibernate. They roost communally during the day to reduce heat loss. A half dozen or more flyers may cuddle during daylight hours before venturing out on nocturnal foraging trips. It turns out that cuddling is an effective technique for reducing heat loss and staying warm.

In nature, however, for every adaptation there is often an equal counter adaptation. Weasels, with their long lean bodies, find their way into Chipmunk dens for easy meals. Mink can plunder Muskrat lodges. Fishers and Pine Martins wreak havoc on squirrel dens.

As I pondered how wildlife deals with extreme cold and snow, I concluded that most species can handle almost anything that nature delivers. Two exceptions, however, come to mind. Ice storms are devastating because ice forms an impenetrable barrier. Ice traps things both beneath and above it. It makes foods almost unattainable. This is the one time it is essential to keep bird feeders well supplied.

Wild animals can deal admirably with almost any conditions winter offers. When winter weather turns extreme, my advice is to worry more about people than wildlife. –Pittsburgh Post Gazette