Here in Bradford County, we had very cold temperatures during December and January, and then, in January, a snowstorm brought life to a standstill. Feb. 7-8 were billed as the coldest days in ten years.

The cold temperatures and snowstorm curtailed our activities. In our younger days, Mary Alice and I would have gone for a walk in the middle of a snowstorm, however, during this snowstorm, we were content to stay in front of the wood fire and watch the birds come in to our feeder.

I remember one January snowstorm when I decided to go for a walk in the winter woods, with a plan to take photos of wildlife activity. The ground was blanketed with ten inches of snow, the wind was blowing and the temperature was in the low 20s. After about an hour, I was more than ready to return to my vehicle and turn the heater on full blast.

As I sat there in the warm truck I marveled at how the insects, birds, and animals are able to survive in such a harsh environment.

Beneath the blanket of snow and fallen leaf duff and tucked in the crevices of tree bark, I knew there were insects, eggs, seeds and even sleeping animals waiting for the arrival of spring. However not all the animals were tucked away and sleeping since I saw many animal tracks, including those of squirrels, deer, turkeys, rabbits, mice and of course many songbirds.

There are some animals, such as the woodchuck, chipmunk, meadow jumping mouse and woodland jumping mouse, that are in a deep sleep known as hibernation.

Some insects, such as the monarch butterfly, migrated south to the mountains in Mexico. The Isabella tiger moth spends the winter in the larval stage as the wooly bear caterpillar. The wooly bear caterpillar, which creates its own body’s antifreeze, crawls under a log or other protective place, where it remains dormant throughout the winter. The eastern tent caterpillar moth over winters in the egg stage. The female lays her eggs, in one bunch, in a ring around either a cherry or apple twig. The eggs are encased in a foam that hardens and allows the eggs to become solidly attached to the twig, where they are protected from the cold by glycerol, an antifreeze chemical that was once used in car radiators.

Many other insects winter over in cocoons, while the goldenrod fly injects an egg into a young and growing goldenrod stem. Chemicals, which are either injected with the egg or produced by the young larva, cause the plant to produce a thick growth called a gall. This gall has soft tissue inside and a hard wood-like exterior. The larva feed upon the plant. By late summer, the larva stops growing and begins to chew an escape tunnel all the way to the hardened outer shell, but not through.

This escape tunnel is made by the larva because the adult gall fly does not have a chewing mouthpart and would remain a prisoner inside the gall. The larva will make its own antifreeze and spends the winter inside the gall. In the spring, the larva pupates into an adult fly and breaks through the outer shell. The fly can do this because it is equipped with a hard section on its head, which is used to break free.

Once free of the gall the fly will begin anew the cycle of laying eggs on the young goldenrod plants.

While other animals, such as the wood frog, will literally become frozen during the winter months, enabling this frog to live farther north than any other amphibian. The wood frog hibernates in the woods, close to snowmelt ponds, which gives it a head start in the spring, allowing the wood frog to reproduce quickly before these ponds dry up. When the temperature begins to drop the frog’s liver starts converting glycogen into glucose, which acts as an antifreeze.

The blood passes the glucose to the vital cells, which are then protected from freezing on the inside, however, the remainder of the frog’s body turns to ice and the organs — even the eyeballs and brain — deprived from blood will stop working. It is effectively the living dead. The painted turtle is also able to do this too.

When the spring thaw comes the frog’s heart starts beating and pumps blood containing clotting proteins throughout the body, which stops the bleeding from wounds that are caused by the jagged ice crystals. After the air temperatures reach 50 degrees for several days, the frog quickly comes back to life and heads for the nearest vernal pool, where it begins calling for a mate.

Often this first singing is heard even before the snow and ice have completely melted from the woods.

Mary Alice is always concerned about how our feathered friends can survive in such a harsh environment. While some birds do migrate south, this is also a hardship. Birds have many ways to survive the harshness of winter. A bird’s feathers provide remarkable insulation against the cold, and many bird species grow extra feathers as part of a late fall molt to give them thicker protection in the winter. The oil that coats the feathers also provides insulation as well as waterproofing.

The legs and feet of a bird are covered with specialized scales that minimize heat loss. A bird can also control the temperature of its legs and feet separately from its body by constricting blood flow to its extremities, which reduces heat loss even further.

Even small birds can build up fat reserves to serve as insulation and extra energy for generating body heat. Many birds will gorge during the fall when food sources are abundant, giving them an extra fatty layer before winter arrives.

Birds will fluff out their feathers to create air pockets for additional insulation during cold temperatures. It is not unusual to see a bird standing either on one leg or crouched to cover both legs with its feathers as a shield from the cold. Birds can also tuck their bills into their shoulder feathers for protection.

Shivering is a way for a bird to raise its metabolic rate and generate more body heat as a short-term solution to extreme cold. While shivering does require more calories, it is an effective way to stay warm.

We humans shiver, but it doesn’t increase body temperature. It only aids the body temperature from falling any lower. Shivering is our body’s first response to being cold and raises our body’s metabolic rate. Minor shivering can produce 20-25% of the warmth our bodies produce. Violent shivering can increase heat production by as much as 400%. Although shivering does not make one feel warmer, it does prevent further heat loss. Shivering cannot replace any warmth the body has already lost.

When I returned home from that winter walk, Mary Alice had kept the fire in the kitchen’s wood stove going and she made me a cup of hot chocolate, and this got me thinking that we also have our own ways to survive the cold winter months.

Bill Bower is a retired Pennsylvania Game Commission Wildlife Officer. Read his blog and listen to his podcasts on the outdoors at www.onemaningreen.com.