Tuesday, March 11, 2014
Sub-zero temperatures? Polar vortex? Really flippin’ cold outside?
As people in Maine fret, fight and flee the cold, wildlife are faring far better than you may think, biologists say. Just watch how wildlife survive the coldest of winters, and maybe the minus-10 on your thermometer won’t scare you so much.
Doug Hitchcox, staff naturalist at Maine Audubon, said even the smallest of creatures, birds that weigh just ounces, survive the extreme cold just fine.
Heck, the black-capped chickadee, the state bird, weighs less than half an ounce and thrives here year-round.
Finding food is the toughest challenge, Hitchcox said, but in Maine where there is so much protected and open land and where so many bird lovers throw out seed, native birds do quite well in cold winters.
Some birds that stay in Maine in the winter change their diets, Hitchcox said, like the northern flicker, which prefers ants but will turn to fruit and seed in winter.
Birds have other adaption methods. Feathers that help them glide also help with insulation. And Hitchcox said they can fluff those feathers up or tuck their feet or heads inside of them to trap body heat and warm extremities.
Large mammals survive by growing longer coats, adding body fat in the fall or hibernating in cavities, sometimes huddled together in colonies to better use body heat.
State deer biologist Kyle Ravana said going into the cold snap two weeks ago, Maine’s whitetails looked “fat and sassy” thanks to back-to-back mild winters that helped the herd grow strong, and also because they found plenty of food on the landscape in the fall.
While the cold and snow make it difficult for deer to survive, Ravana said this weather needs to extend over several weeks for Maine’s deer herd to suffer.
“We’ll look at a couple of months before we really get nervous,” Ravana said.
And he said it is the deep snow, more than these Arctic temperatures, that threaten deer survival.
“The big thing for deer really is the snow. That’s where they lose a lot of their energy traveling through deep snow. And when there is ice, they have a harder time walking on the ice. But right now it’s too early to tell,” Ravana said.
Meanwhile, at the Center for Wildlife in Cape Neddick, director Kristen Lamb said some of what hampers wildlife in the winter is not caused by nature but by people.
At the animal rehabilitation center that sees an average of 1,600 injured birds, mammals and reptiles each year, the top reason injured animals are brought in is because of collisions with cars, Lamb said.
Another human-related activity that hurts wild animals’ ability to make it through a hard winter is the cleaning up of old stumps, trees or snags for the sake of a tidy yard. When people remove old trees from their property, they deprive wildlife of a safe, warm shelter to spend the winter.
“These provide nesting cavities and winter habitat for many of our wildlife species. People can help with this by keeping snags on their properties,” Lamb said.
That said, Lamb agreed Maine’s wild critters are remarkable in their rugged resilience. She pointed to the chickadee, which drops its temperature as much as 20 degrees to conserve energy and slow its body during cold weather; and to other birds like the herring gull that have an amazing circulatory and vascular system that keeps those skinny legs warm in icy water.
“New England wildlife are amazingly adapted to harsh and extreme winter conditions,” Lamb said.
Deirdre Fleming can be reached at 791-6452 or at: