Wild Hedgehog Hibernation Success and Climate Change

Climate change is disrupting hedgehog hibernation patterns, with warmer winters causing premature arousal that depletes fat reserves before spring food is available.

Key Facts

Hedgehogs hibernate from November to March in the UK, surviving on fat stores accumulated in autumn
A hedgehog needs to weigh at least 450-500 grams to have sufficient fat reserves to survive hibernation
Warmer winter temperatures cause premature arousal — hedgehogs wake from torpor and burn stored fat without finding food
UK winters have become measurably warmer, with more frequent mild spells interrupting hedgehog hibernation
Underweight hedgehogs found active in November or December often die without intervention from wildlife rehabilitators

Welfare Considerations

Climate-disrupted hedgehog hibernation causes welfare harm through premature arousal events that deplete fat reserves without corresponding food availability. A hedgehog that arouses during a warm December spell may lose significant fat mass before returning to torpor, reducing the reserves needed to survive until spring invertebrates become available. Multiple arousal events across a mild winter can collectively reduce survival probability to near zero for borderline-weight animals. Wildlife rehabilitators across the UK take in thousands of underweight hedgehogs annually that would otherwise die. Creating autumn feeding stations that allow hedgehogs to reach adequate pre-hibernation weight provides direct welfare protection against this climate-linked risk.

What You Can Do

Provide supplementary food — meat-based cat or dog food — in autumn until early winter to support pre-hibernation weight gain
Check bonfire heaps before lighting during October to March as hedgehogs use them as hibernation sites
Contact a local hedgehog rescue if you find an active hedgehog outside in December-February — it likely needs help
Support British Hedgehog Preservation Society and Wildlife Aid Foundation rehabilitation programmes