Black bears hibernate for five to seven months of the year. It was discovered that when there was a slight decrease in their body temperature, there was a huge decrease in the metabolic rates. Several ecologists have performed experiments to test this theory. Barnes et al 2012 performed an experiment on bears in south central or interior Alaska. They captured the bears in late autumn in three different years and transported them to the facilities at the Institute of Arctic Biology. The study measured metabolic rate and body temperature in hibernating black bears( Ursus americanus). To do this, they placed bears inside 0.8 m3 wooden nest boxes containing straw, infrared cameras, activity detectors, and telemetry-receiving antennas Food and …show more content…
The energy to do this is often expensive, especially over an extended period of time. Some mammals are unable to survive this period due to the limitations. Bears have a unique ability to survive hibernation for seven months while other hibernating animals are aroused every four to ten days. Bears hibernate at or near their body temperatures while other mammals hibernate at temperatures closer to the external temperature of the environment (Hellgren 1998). During this period, they do not eat, drink or pass waste out. During hibernation, the metabolic rate, heart rate and other physiological functions of bear are significantly …show more content…
The metabolic processes of hibernating bears did not return to normal as fast as other small hibernators did. The study also revealed that when the body temperature decreased by 1.2°C, the metabolic rate reduced by 47.1% , and stabilized after 2 to 3 weeks of returning to normal body temperature. The heart rate in hibernating bears also decreased by 74%. Martin (2003) also arrived at the same results. In the study, when the body temperature of hibernating bear was 30-34°C, the metabolic rate was greatly reduced. Hellgren (1998) revealed that hibernating bears have body temperatures ranging from 31.2°C to 36°C. The average metabolic rate is 68% of normal basal metabolic rate. Gieser (2004) found that the difference between the ambient temperature and the body temperature of bears is more or less constant despite a reduction in metabolic rate. This is not the same in small hibernators as the difference between the ambient temperature and body temperature of bear is constant when there is a proportional increase in metabolic rate at lower body temperatures.