The barbastelle (Barbastella barbastellus) is a predominantly tree-dwelling species associated with woodland with a high proportion of standing dead wood or storm damaged trees.
Bechstein’s bat (Myotis bechsteinii) is a tree-dwelling species associated with old growth woodland.
Britain’s population of some 10,000 greater horseshoe bats (Rhinolophus ferrumequinum) was until recently restricted to south and west Wales and south-west England.
In Britain, the lesser horseshoe bat (Rhinolophus hipposideros) is now restricted to Wales, the west midlands and south-west England.
The pine marten (Martes martes) is likely to have arrived in Britain and Ireland soon after the end of the last glaciation.
The polecat (Mustela putorius) is of considerable conservation significance in Britain.
The native red squirrel (Sciurus vulgaris) is rare in England and Wales and has been replaced by the introduced grey squirrel in much of its range.
The stoat (Mustela erminea) is widespread and thought to be relatively common across Britain, but are under-studied and poorly understood.
The weasel (Mustela nivalis) is widespread and thought to be relatively common across Britain, but are under-studied and poorly understood.