People’s Trust for Endangered Species (PTES) and NatureSpace are collaborating to develop survey methodology and protocol to produce a more robust map of dormouse presence and distribution within a county. The project is being piloted this year in Sussex, which although well within the dormouse range does not appear to have the widespread populations of counties like Kent and Devon.
The county lies within the southern range of the species, yet dormouse distribution within the county remains poorly understood. We know where dormice are based on the National Dormouse Monitoring Programme (NDMP) sites and records. And there are other locations we know about because of surveys carried our for licence requirements, but these data are biased towards well-monitored woodlands and urban habitats.
To improve our knowledge of where dormice are in the county, we’re going to survey more rural areas, particularly where dormice have not yet been recorded.
Expanding the survey effort
NatureSpace has identified which key areas of Sussex where we know little about whether dormice are present or not. Meanwhile PTES has been working hard to secure permission from landowners to access their land, allowing surveyors to explore under-surveyed hedgerows and woodlands. Help from local farmer cluster groups is proving critical. And we’re also hoping to survey National Trust sites and Wildlife Trust reserves. The team is aiming to collect 60–70 positive dormouse records during the 2025 survey season, which is a challenging but achievable goal.
Time is of the essence. The survey methods that have been shortlisted include footprint tunnels, nest boxes, camera traps and infrared camera surveys.
We are targeting three key habitat types: unmanaged woodland, managed woodland, and hedgerows and linear scrub.
Nest boxes and footprint tunnels will be put up and monitored fortnightly. At each site, a simple habitat questionnaire will also be completed to help understand the relationship between specific habitat types and whether dormice are present.
This is the first large-scale county dormouse survey in the UK to rely on modern detection techniques rather than traditional hazelnut searching. The results are expected to significantly improve our understanding of dormouse presence in Sussex and lay the groundwork for similar surveys across the country.
July 28th, 2025
Image credit Lorna Griffiths