Partitioning of woodland habitat resources by two sympatric species of Apodemus:: lessons for the conservation of the yellow-necked mouse (A-flavicollis) in Britain

In Britain, the conservation status of Apodemus flavicollis at this western edge of its range is poorly understood, as are its specific habitat requirements. We conducted autumn and spring live-trapping studies of A. flavicollis and A. sylvaticus, using standardised transect lines to calculate relative abundance indices for 19 woodlands ranging in size from 2.2 to 113.5 ha in Gloucestershire, south-west England. Habitat features were measured for each woodland. Different habitat structures within woodlands affected the abundance of each Apodemus species. Canopy cover, the number of hard seed/fruit tree species and fallen timber were important variables affecting the abundance of A. flavicollis, while herbaceous cover and height influenced the abundance of A. sylvaticus. Woodland size and recent/ancient age classifications were not good predictors of A. flavicollis abundance. The abundance of A. flavicollis was highest in mature woodlands. Many common woodland conservation management practices may positively affect the local abundance of A. flavicollis in areas within its natural distribution. We suggest that current woodland management practices designed to conserve more immediately threatened species will also benefit A.flavicollis, especially in marginal areas of its range in Britain. (C) 2000 Published by Elsevier Science Ltd. All rights reserved.