Hedgehog Hibernation: Welfare During Winter Dormancy

Hedgehog hibernation is a critical but vulnerable period during which individuals must enter and maintain torpor safely to survive winter — and human disturbance can be fatal.

Key Facts

UK hedgehogs typically hibernate between November and March, though mild winters can produce erratic hibernation patterns
A hedgehog must weigh at least 450-500g before hibernation to survive winter — underweight hedgehogs require intervention
Climate change is disrupting hibernation timing, with hedgehogs waking during mild spells and depleting critical fat reserves
Hedgehogs found active in daylight during winter are almost certainly in trouble and need immediate help
The British Hedgehog Preservation Society (BHPS) coordinates rehabilitation referrals across the UK

Welfare Considerations

Hibernation is physiologically demanding: the hedgehog must accumulate sufficient fat reserves to sustain basic metabolic function through months of torpor. Underweight hedgehogs that attempt hibernation typically do not survive. Disturbance during torpor — by garden machinery, bonfire construction, or children investigating hibernation nests — forces hedgehogs to warm up and expend energy reserves prematurely. Climate-driven mild spells interrupt torpor and force hedgehogs to forage when food is unavailable, draining the reserves they need to re-enter hibernation safely. Both disturbance and climate effects represent welfare harms that vigilant humans can partially mitigate.

What You Can Do

Weigh any late-autumn hedgehog you encounter — under 500g means it needs help before winter
Contact the BHPS helpline or your nearest hedgehog rescue if you find an underweight or winter-active hedgehog
Never disturb garden areas that might contain hibernation nests between November and March
Provide supplementary food (cat or hedgehog food, water) in late autumn to help hedgehogs build reserves
Create log piles and leaf mounds as hibernation habitat in your garden — placed in quiet, undisturbed corners