Myth: Hazel Dormice Are Vanishing — New Data Shows Survival Boost in Warm Summers
In a 0.5‑hectare plot near Little Marlow, researchers recorded 45 hazel dormice, the highest density ever noted in the Chilterns. This surge signals that the species, long plagued by habitat loss and climate stress, may be rebounding. The finding underscores the importance of monitoring subtle ecological changes. It also raises hope that conservation efforts are finally paying off.
What Happened: 2024 Dormouse Survey Data
The Forestry Commission’s annual Dormouse Monitoring Programme released its 2024 results on 15 September. Teams surveyed 50 sites across the Chilterns, Oxfordshire, recording 3,200 individual dormice—up from 2,800 in 2020. A notable spike was observed at the Hainault Wood site, where density reached 120 individuals per hectare for the first time in the programme’s history. Data were collected by trained volunteers from the Wildlife Trusts and local citizen scientists using nest box counts and camera traps.
Hazel dormice can hibernate for up to six months while losing up to 30% of their body weight, yet they resume breeding within weeks of emerging.
