The Development of Non-Invasive Genetic Methods for Bats of the British Isles

Bats play an important role in the ecosystem of the British Isles, but are vulnerable to population decline due to human activities and thus are the subject of much scientific research. Non-invasive DNA sampling is commonly used in scientific studies of wild mammal species, but is still used in relatively few genetic studies of bat species. The overall aim of this thesis is to develop molecular techniques for application to the bat species of the British Isles. Species-specific real-time PCR primers, targeting the cytochrome b mitochondrial DNA gene, were designed for the identification of eighteen resident bat species in the British Isles. These primers were applied to a field survey of bat roosts in Ireland, in Counties Galway, Kildare, Waterford and Wexford, from which non-invasively collected faecal DNA samples were obtained. The lesser horseshoe bat (Rhinolophus hipposideros) is one of Ireland’s rarest bat species, and its population is monitored nationally each summer by emergence counts of at known summer roosts. The sex ratio of adult bats present in these roosts is an important part of calculating national population estimates, but no empirical data on this sex ratio are available from Ireland. Real-time PCR sex typing assays for the lesser horseshoe bat were designed, targeting the ZFX, SRY and DBY genes. Using these sex typing assays and previously published microsatellite DNA markers, the sex ratio of adult bats was examined at six lesser horseshoe bat summer roosts across the species’ range in Ireland using faecal DNA samples. The lesser horseshoe bat’s range in Ireland is limited to geographically isolated parts of the counties of the west coast. The population genetics of the species was examined using microsatellite genotyping of faecal DNA samples from 21 colonies from across its range, to assess the level of interbreeding and possible risk of inbreeding within this population.