Body Surface and Core Temperatures of Hibernating Black Bears

Hibernation in black bears: independence of metabolic suppression from body temperature.

Black bears hibernate for 5 to 7 months a year and, during this time, do not eat, drink, urinate, or defecate. We measured metabolic rate and body temperature in hibernating black bears and found that they suppress metabolism to 25% of basal rates while regulating body temperature from 30° to 36°C, in multiday cycles. Heart rates were reduced from 55 to as few as 9 beats per minute, with profou...

Body Mass and Lipid Changes by Hibernating Reproductive and Nonreproductive Black Bears

Insights from the Den: How Hibernating Bears May Help Us Understand and Treat Human Disease.

Hibernating brown bears (Ursus arctos) and black bears (Ursus americanus) spend half of the year in a physically inactive state inside their winter dens without food intake and defecating and no or little urination. Under similar extreme conditions, humans would suffer from loss of lean body mass, heart failure, thrombosis, azotemia, osteoporosis, and more. However, bears exit the den in the sp...

Physiological reactions to capture in hibernating brown bears

Human disturbance can affect animal life history and even population dynamics. However, the consequences of these disturbances are difficult to measure. This is especially true for hibernating animals, which are highly vulnerable to disturbance, because hibernation is a process of major physiological changes, involving conservation of energy during a resource-depleted time of year. During the w...

Wound healing during hibernation by black bears (Ursus americanus) in the wild: elicitation of reduced scar formation.

Even mildly hypothermic body or limb temperatures can retard healing processes in mammals. Despite this, we observed that hibernating American black bears (Ursus americanus Pallas, 1780) elicit profound abilities in mounting inflammatory responses to infection and/or foreign bodies. In addition, they resolve injuries during hibernation while maintaining mildly hypothermic states (30-35 °C) and ...