Caves and Mines
The caves, abandoned mines and associated buildings of south Devon, including south-east Dartmoor, contain the largest population of greater horseshoe bats in western Europe, and the only population containing more than 1000 adults. Indeed, the area is believed to have about 30% of the British population of this bat, which is threatened throughout Europe.
In the summer these bats form maternity roosts, generally in large old buildings. In the winter the bats hibernate in caves, abandoned mines and other undisturbed sites.
The caves at Buckfastleigh also contain the blind shrimp Niphargus glennei which is endemic to Britain. The species is known from only fourteen sites, all from south Devon except one in the north of the county. Numbers and population trends are not known.
Bats, other than the greater horseshoe, also hibernate, roost and breed in the caves, mines and buildings of Dartmoor Natural Area. Most notable of these in the lesser horseshoe bat, of which there is at least one large nursery, of 160 adults, in a building not far from Buckfastleigh. This colony is considered to be of national importance. Other bats present in the Natural Area include the pipistrelle, whiskered bat, brown long-eared bat and the nationally rare barbastelle.
The nationally scarce luminous moss Schistostega pennata occurs in mine adits and other dark rocky places. Its peculiar light-reflecting power has been said to give a beautiful golden-green lustre to the plant and seems to fill the crevices and caves where it grows with light.
Protected sites include Buckfastleigh Caves and Haytor and Smallacombe Iron Mines which are SSSIs. Together with three other SSSIs in south Devon they form a candidate Special Area of Conservation under the European Habitats Directive. Both Hembury Woods and Lydford Gorge SSSIs contain old mine adits which are used by bats.
Current factors affecting the habitat include new roads, houses and other developments which affect local foraging areas for bats. The grilling of caves and mine adits can prevent access by bats (as well as people) and caving can lead to damaging disturbance to roosting and hibernating bats; changes in water quality and quantity affect freshwater shrimps.