National scale habitat suitability analysis to evaluate and improve conservation areas for a mature forest specialist species

Abstract

Species distribution modelling is an important tool to inform conservation, particularly if combined with site prioritisation approaches. Results can then be used in both suggestion of new protected areas as well as evaluation of the existing ones. We applied MaxEnt analysis to a species of mature forests, the Eurasian Pygmy Owl (Glaucidium passerinum), which is recognised as a biodiversity indicator species. Furthermore, we used habitat suitability and uncertainty maps in site prioritisation for conservation and evaluation of the existing nature conservation area (NCA) network. We found species to be strongly positively associated with time since forestry activities at a local scale (25ha) and abundance of mature forests from local through home range (450ha) to landscape (1960ha) scales. The sum of habitat suitability as a proxy for apparent population allowed us to estimate that the existing NCAs hold only 23% of the population. We found 68% of priority sites (PS) for species conservation to be outside NCAs. Strict forestry restrictions form the most suitable conservation regimes, with more than 51% of PS in NCA network having insufficient regimes. Inclusion of PS in NCAs would increase the network to 26% of the national territory with 41% of the species apparent population. Currently, the most suitable conservation regimes cover less than 2% of the country area.

Keywords

• Eurasian Pygmy Owl, species distribution modelling, conservation prioritisation, protected area evaluation