It’s that time, the bears are getting ready to den up for the winter. While known, bear hibernation is not fully understood by many. Hibernation preparation begins immediately when they awake in the spring. There are five distinctive steps to this
During hibernation, the bear go through five different stages.
The spring until midsummer or fall is the time when the bear are in their normal activity. If food and water are available, the bear will consume about 5,000 to 8,000 calories each day. If they are unable to consumer enough food and water during this time, they will be unable to successfully hibernate in the winter.
This stage is known as hyperphagia. During this stage, bear eat and drink excessively as they build up fat stores for hibernation. When food and water are plentiful, black bear have been know to eat as many as 15,000 to 20,000 calories a day. The need large amounts of water to process the food and flush nitrogenous waste from their bodies.
After they go through hyperphagia, it is time for their fall transition. During this time, their metabolic processes change as they prepare to hibernate. Their heart rate slows from the normal 80-100 beats per minute to about 50-60 beats per minute. During sleep, their rate is about 22 beats per minute. The normal beats of a sleeping bear are between 66-80 per minute. The bear continue to drink, but will start to eat less. As they prepare to hibernate, they can rest as much as 22 hours a day.
Hibernation begins. The bears’ breathing slows to about half of their normal rate. They take a breath only once every 45 seconds. Their heart rates slows even more. It can drop periodically to between eight and 21 beats per minute. They burn about 4,000 calories per day. They do not eat, drink, urinate or defecate during hibernation.
This stage is known as walking hibernation. During the first two to three weeks after the bear leave their hibernation den, their metabolic processes return to normal levels. During this time, they will continue to eat and drink less than they do in the summer months. Their bodily waste processes are also reduced. Once this time is past, the bears resume their normal summer activity.
Bear that are in hibernation can be hard to wake if they are disturbed. The bear that are in warmer climates may not be in as deep hibernation as bear in colder areas. Female bear often give birth in the den during the winter months. The mother bear tend to be in a lighter state of hibernation as they awaken to care for their young.
Should you stumble upon a hibernating bear, the best thing to do is to quietly leave the area.