Black bears enter a remarkable physiological state during winter hibernation that conserves energy, but human disturbance of denning bears causes serious welfare impacts during this vulnerable period.
Bears disturbed during hibernation face acute welfare consequences. Arousal from torpor is energetically costly - the metabolic cost of emergency arousal can consume fat reserves needed for the rest of winter. Bears that abandon dens mid-winter before conditions support foraging face starvation in landscapes with no available food. Cubs born during denning are entirely dependent on their mother - disturbance separating mother and newborn cubs results in cub death. The increasing frequency of disturbance from human winter recreation in bear habitat makes den protection an important but often overlooked welfare issue.