Radio tracking of greater horseshoe bats at Caen Valley Bats SSSI, North Devon

Summary

The activity patterns of greater horseshoe bats Rhinolophus ferrumequinum roosting at Caen Valley Bats Site of Special Scientific Interest (SSSI) were investigated over two 7 night periods in May and August 2002. A total of 20 bats of both sexes were radio-tracked over the two sessions.

The bats regularly commuted five kilometres to foraging areas and were recorded travelling over seven kilometres away from the roost. The total area used by the population covered at least 100 square kilometres.

Foraging occurred primarily in and around wet woodland, scrub, grassland adjacent to tall, bushy hedgerows and tree lines, and along tree-lined watercourses.

A total of 14 foraging areas were identified during the study. The most significant foraging areas were: Saunton, Braunton, Braunton Great Field, Braunton Marsh and Braunton Burrows in May and Georgeham in August.

The main commuting routes used by the bats leaving the SSSI were identified as north and south along the Caen valley, west to Georgeham and east along Knowle Water towards Barnstaple.

Two significant night roosts were identified.

Recommendations are made for further survey and conservation work on foraging areas, commuting routes and roosts.