This spreadsheet is the underlying data for the biodiversity indicator C8, Mammals of the wider countryside (bats).
Bat populations are considered to be a good indicator of the broad state of wildlife and landscape quality because they utilise a range of habitats across the landscape and are sensitive to pressures in the urban, suburban and rural environment. All bats and their roosts are protected by domestic and European legislation. The UK is a signatory to the EUROBATs agreement, set up under the Convention on Migratory Species, with the intention of conserving all European bat populations. The wider relevance of bats as biodiversity indicators is presented in Jones et al. (2009).
The indicator shows changes in the population size of eight widespread bat species, based on summer field surveys and roost counts and winter hibernation counts. Population change between 1999 and 2014 is analysed using a statistical model developed by the Bat Conservation Trust.
This is one of a suite of 24 UK biodiversity indicators published by JNCC on behalf of Defra; the latest publication date was 19 January 2016 - for indicator C8 the latest data are for 2014.