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Providing evidence to improve practice

Individual study: Trial of a bridge for reconnecting fragmented arboreal habitat for hazel dormouse Muscardinus avellanarius at Briddlesford Nature Reserve, Isle of Wight, UK

Published source details

White I.C. & Hughes S.A. (2019) Trial of a bridge for reconnecting fragmented arboreal habitat for hazel dormouse Muscardinus avellanarius at Briddlesford Nature Reserve, Isle of Wight, UK . Conservation Evidence, 16, 6-11

Summary

The hazel dormouse Muscardinus avellanarius has experienced a marked decline in the UK in recent years, attributable in part to habitat fragmentation associated with an expanding road and rail network. A number of arboreal crossing structures have been installed in the UK to reconnect fragmented habitat, but the only proven usage of such structures by wild hazel dormice has been associated with a large-scale land bridge. This has highlighted the need for affordable, evidence-based alternative designs. We tested the effectiveness of a new dormouse bridge, previously shown to be used by Japanese dormice Glirulus japonicas in Japan, in reconnecting two woodland patches bisected by a railway in southern England. Hazel dormice were recorded on the bridge within nine hours of its erection and exhibited a clear preference for using the bridge, with more than ten times more observations of dormice on the bridge compared to crossing the railway at ground level. Red squirrels Sciurus vulgaris, another rare UK mammal, were also recorded on the bridge. The trial provided evidence of the effectiveness of this design of crossing structure in reconnecting arboreal habitat for hazel dormice and other wildlife, with implications for hazel dormouse mitigation in infrastructure projects.