Important underground roosts for bats in Bulgaria: current state and priorities for conservation

Bulgaria has a very rich bat fauna and large colonies of bats can be found in caves, mines other underground roosts. Respectively, there are more than 107 roosts that listed as important sites, most which protected by statutory laws national or international importance. Despite the existence formal protection, many face anthropogenic disturbances due to popularity outdoor activities, such caving lack actual regulation. Currently, evaluation was only based on size colony presence species. However, this approach is limited contain high diversity neglects ones biotic importance highly threatened various threats. Here, we evaluated conservation priorities identified vulnerable Bulgaria, using Bat Cave Vulnerability Index proposed measures adequately protect sites. We 32% Bulgarian assessed at "high priority" level for while 39% "medium may require constant monitoring. This novel integrative applied roost prioritisation country enabled detection sites need urgent attention first step establishing better strategies monitoring network Bulgaria.