A comprehensive index for threatened biodiversity valuation

We present a new comprehensive index for mapping the relative conservation value of threatened biodiversity. The index is based on explicit criteria to (1) select threatened species according to regional government responsibility for species’ conservation; (2) combine species’ presence by means of weighting factors based on differences in threat status, sensitivity to disturbance, functional role, and amount of knowledge; and (3) map species distributions at the scale of 1 km×1 km UTM squares or lower from the information available. We tested the performance of the index in the forest of Andalusia (southern Spain), an extensive European region of 87,268 km2, with 43,864 km2 (ca. 50%) classified as forest habitats. All species included in the Annexes of the European Birds and Habitats Directives inhabiting the target area, plus the regionally endemic species either ‘Critically Endangered’ or ‘Endangered’ not (yet) covered by the Directives were selected. The final list included 224 speci...