Physiological reactions to capture in hibernating brown bears

Area of Science:

• Wildlife biology
• Animal physiology
• Ecology

Background:

• Human disturbance impacts wildlife, but effects on hibernating species are challenging to quantify.
• Hibernation involves significant physiological changes for energy conservation during resource scarcity.
• Hibernating animals are particularly vulnerable to disturbances during this critical period.

Purpose of the Study:

• To assess the physiological and behavioral impacts of winter capture on subadult brown bears (Ursus arctos).
• To quantify the recovery time for body temperature and heart rate following disturbance during hibernation.
• To evaluate the effects of capture on hibernation patterns and den emergence timing.

Main Methods:

• Biologgers were used to record body temperature and heart rate in 15 subadult brown bears before, during, and after winter captures (2011-2015).
• Recovery time for physiological parameters to return to pre-capture hibernation levels was estimated.
• Captured bears' hibernation patterns and den emergence were compared to a control group of undisturbed bears.

Main Results:

• Captured bears exhibited increased body temperature and heart rate during the event.
• Physiological parameters took 15-20 days to return to normal hibernation levels post-capture.
• Evidence suggests winter captures lead to delayed den emergence in brown bears.

Conclusions:

• Winter captures impose significant metabolic costs on hibernating brown bears, requiring substantial recovery time.
• Disturbance during hibernation can disrupt normal physiological processes and alter critical life-history events like den emergence.
• Understanding these impacts is crucial for managing wildlife populations in human-altered landscapes.