Bears work in either the summer or the fall to collect food for the winter.
because there is no food during winter
bears sleep through winter to conserve food, especially during winter when food is short, tapping energy reserves, body fat, at a slow rate. you can find out more at here: http://en.wikipedia.org/wiki/Hibernation
Brown bears hibernate in the winter because there isn't enough food.
The coming of winter and its instincts. Bears' instinct make them hibernate before winter as food is scarce in the winter, so they stock up (eat) a huge quantity of food and doze off for a season.
They hibernate in the winter when it is the coldest and food is scarce. Contrary to popular belief, not all bears go to sleep in the beginning of winter and emerge in the spring. Most bears will come out a few times during the winter but go back in to continue to hibernate.
black bears make there habitat by going in cave for the winter but i do not know how they get there food
Basically little or nothing, their Metabolism slows down to a point where they seem semi-comatose and spend most of the winter asleep [hibernation] in a sheltered spot.
Yes, polar bears eat up alot of food to last a whole winter and when they go into hibernation, they digest the food slowly, making it last the winter. This is all while they are in hibernation, they eat alot of food before they go into hibernation.
Bears hibernate until spring because during the winter, their food supply shrinks. If they were to stay awake through the winter, they would die from starvation.
They can dig in the snow, swim, hunt for seals, and whatnot.
they start to find food and start looking for a cave.