Hazel Dormice on Road Verges
• Small, nocturnal rodent • Successional feeder • Hibernate • Low fecundity • Highly arboreal • Inhabit: – Successional woodland – Woodland edges/rides – Scrub
• Shrub diversity • Connected vegetation
Hazel dormice have declined in the UK by 51% since 2000 Hazel dormice have been lost from 17 English counties
Are dormice more, or less, abundant on roadside verges than at NDMP sites?
NDMP data • Uses boxes • Looks at positive sites • 50 boxes will survey an area of 1.38 ha • NDMP data can be split by region, by month and by year Estimate of dormouse population using boxes per hectare
Licence Return data • Uses nest tubes • Looks at positive sites • 50 nest tubes will survey an area 0.765ha • Licence data can be split by region, by month and by year
Estimate of dormouse population using tubes per hectare
Region
Season
2014-18 mean per NDMP ha
2014-18 mean per road ha
Difference
SW England
Spring
1.50
4.01
2.68
S England
Spring
1.52
0.87
0.57
SE England
Spring
1.69
1.97
1.16
E England
Spring
1.18
1.96
1.66
Wales
Spring
1.38
5.23
3.80
England & Wales
Spring
1.34
3.01
2.24
SW England
Autumn
3.22
13.51
4.19
S England
Autumn
3.76
9.64
2.56
SE England
Autumn
4.23
5.89
1.36
E England
Autumn
Wales
Autumn
2.36
7.84
3.32
England & Wales
Autumn
3.07
7.91
2.57
Why are road verges good? The higher densities of dormice in roadside habitats suggests these sites could be optimal and among some of the best habitat there is for the species • Well-developed shrub layer present on many roadside verges • Fewer standard trees (due to H&S ) • Lower deer impacts • Higher light levels • Excellent connectivity into the the wider landscape
Small arboreal bridges Small arboreal bridges for dormice can aid on site roadside mitigation schemes by making more areas of on-site habitat available to dormice. Captive dormice will travel at least 60m in a metal mesh tube
In Japan a small bridge was shown to have been used over 800 times in 3 months by a range of mammals.
Small arboreal bridges for dormice can aid roadside mitigation schemes by making more areas of on-site habitat available A specific design in the UK has now been developed by Animex with proven and preferential usage The cost of arboreal bridges has substantially declined. A bridge can be retrofitted to an existing structure or installed as a standalone.
People’s Trust for Endangered Species, 3 Cloisters House, 8 Battersea Park Road, London SW8 4BG Registered charity no 274206