Bitter Cold and Survival
During a stretch of bitter cold winter weather, the survival of wildlife is dependent on many factors. Some of these factors include the location of the animal, its life stage, and access to food.
Mammals such as deer, rabbits, squirrel, and bear have a winter coat that has protective covering. They add a fat layer during the fall, they tend to huddle together during cold weather for increased insulation, and they try to find protected areas like boroughs, caves, and tree cavities to wait out the inclement weather.
Birds that overwinter also add a fat layer, and they fluff up their feathers to create air pockets for insulation. Birds also seek out sheltered areas like evergreens, tree cavities, and bird houses to escape the elements. Additionally, birds try to maximize energy intake when they are eating, and minimize energy expenditure when waiting out the bitter cold. Starvation is a very real hazard for small birds when it is inclement. So prolonged periods of cold with little to no food spells doom for small birds. It may be uncomfortable to go out and fill up the bird feeder in the bitter cold, but the birds will thank you for it.
Most insects are inactive during the winter, so where they are found during the season has a lot of bearing on whether or not they will survive. Ticks, for instance, tend to overwinter under leaf litter on the ground. This sheltered area tends to insulate them during very cold weather, especially if they are covered under an insulating blanket of snow. Gypsy moths overwinter as egg masses that are attached to trees, rocks, or any other convenient structure. Those gypsy moth egg masses that are located in exposed areas can succumb during frigid weather, while those that are in protective areas or covered with snow have a good chance of surviving low temperatures. Insects like hemlock woolly adelgid attach to their host plant and continue feeding throughout the winter. It is thought that these insects experience heavy mortality if the temperatures dip down below five degrees Fahrenheit. Mosquitos are very prone to winter mortality, but the mosquito has such a large reproductive capacity that it takes only a few bugs to make many more, later in the summer.
Article by Mike Kay, Frederick.forestryboard.org