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Name:  Scott
Status:  other
Age:  30s
Location: N/A
Country: N/A
Date: 2000-2001


Question:
I was watching a Discovery Channel show with my 13 yr old son, Jason, and we thought we heard them say that bears do not technically hybernate. Did we hear correctly? If so, what is the difference between hbernation and what bears do?


Replies:
During true hibernation the animal's body temperature drops to around 40 d. f., heart rate and slows to just a few times a minute, and respiration is very slow. Bears and some other mammals sleep through much of the winter but with these essential functions slowed only slightly from active state, and can be easily awakened.

J. Elliott


Bears are not true hibernators. Hibernation refers to a state in which the animal gives up trying to maintain a constant body temperature because it is "expensive" in terms of the amount of food available to maintain that high body temperature. Small animals with high metabolic rates such as rodents, hummingbirds, insectivores, bats, etc. are true hibernators. Their metabolic rate drops, their body temperature drops almost to the level of the surroundings and shows little response to external stimuli. These animals collect and eat a lot of high caloric food (ie, nuts) to store calories to make it through. Bears are not true hibernators because their body temperature drops only a few degrees and they show only a moderate drop in metabolic rate. Females often give birth to cubs during the winter. They actually are sleeping deeply, but not hibernating.

Van Hoeck


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