Last week I wrote about winter migration and this week I would like to cover adaptation and hibernation. Deer eat leaves, twigs, acorns, plants and even some fruit, but come fall, can eat close to 10 or more pounds a day to build up their fat reserve. In the fall a Deer’s coat changes to a darker color (guard hairs) that absorbs sun to keep them warm and their new winter fur is also denser for insulation. When snow covers the ground, deer will still browse but food is much harder to find. At this time, they start to live off that fat reserve, travel less and will bed down under evergreen trees for longer periods. Not only will bedding down longer help lower their metabolism, but areas like this will also protect them from wind and cold. Other animals that their fur changes for the winter in the Northwoods, are coyotes, wolves and bobcats.

There are some Northwoods animals that truly hibernate (mostly snakes, frogs and turtles) but other animals like Raccoons, Skunks and Bears will go into a state called torpor. Torpor is where the animals heart heat rate and breathing slow and their body temperature lowers. Some animals can wake every couple of weeks to look for food and water, but Bear will stay in torpor all winter. During this time Bears do not eat, drink, urinate or defecate and will lose up to 30 percent of their body weight. One amazing fact is female Bears can give birth (1 to 3 cubs) and nurse during torpor. There are many more things I could cover on individual animals but that could be another subject at a later date.