Wild Hedgehog Hibernation and Welfare

Hedgehogs face increased hibernation failure risks from climate variability, habitat fragmentation, and insufficient pre-hibernation weight gain.

Key Facts

Hedgehogs need to reach 600 grams before safe hibernation, with 700 grams considered optimal
Climate-related warm autumns delay hibernation, reducing the critical pre-hibernation foraging period
Juvenile hedgehogs born late in summer rarely achieve adequate weight before winter
Disturbed or lightweight hibernating hedgehogs that wake may die from exhaustion in cold conditions
Supplementary autumn feeding of underweight hedgehogs is a direct welfare intervention that improves survival

Welfare Considerations

Hedgehog hibernation welfare is increasingly compromised by climate change and habitat degradation acting together. Warmer autumns delay the start of hibernation, but do not reliably provide the extended foraging period needed for adequate weight gain — insect availability in warm but late autumns may not match a hedgehog foraging capacity. Juvenile hedgehogs born from late litters face the greatest challenge: they have only weeks to gain the weight needed for safe hibernation that is gained over months by spring-born animals. Supplementary feeding of underweight hedgehogs before winter — particularly juveniles found below 600 grams in October — directly prevents hibernation deaths and represents one of the most welfare-positive interventions available to garden wildlife supporters.

What You Can Do

Provide supplementary food for garden hedgehogs throughout autumn, particularly in October and November
Weigh garden hedgehogs in late autumn and contact a wildlife rehabilitator if individuals appear underweight
Create hedgehog-friendly gardens with compost heaps, log piles, and undisturbed leaf piles for hibernation sites
Never disturb a hibernating hedgehog as waking costs fatal energy reserves that cannot be replaced in winter