Virginia Tech study links black bear hibernation to daylight and temperature

Researchers at Virginia Tech have discovered that American black bear hibernation is influenced by more than just falling temperatures. A study published in the journal Proceedings of the Royal Society B: Biological Sciences suggests that daylight length, or photoperiod, plays a critical role alongside temperature in regulating hibernation cycles.

By analyzing over 22,000 hours of video footage from the Black Bear Research Center, scientists observed that while temperature is the dominant factor at the start of hibernation, daylight length works in tandem with temperature during other key phases, such as pre-hibernation feeding and den emergence.

This finding has implications for understanding how climate change affects wildlife. Because daylight patterns remain constant while temperatures fluctuate due to global warming, the decoupling of these two environmental cues could provide bears with conflicting signals regarding when to feed, enter dens, or emerge.