Hazel dormice have declined by 70% in the UK and face welfare threats from habitat loss, woodland fragmentation, and climate disruption of hibernation.
Dormice aroused from hibernation by mild spells in autumn or winter face critical welfare risks from fat depletion. Each warm-weather arousal costs significant fat reserves that may not be recoverable before true winter. Dormice that enter hibernation underweight have very low survival rates. Habitat fragmentation prevents dormice from finding sufficient food in autumn to build adequate reserves. Woodland connectivity is the most important welfare intervention at landscape scale.