Species and space: a combined gap analysis to guide management planning of conservation areas

Abstract

With accelerating global declines in biodiversity, establishment and expansion of conservation areas (CAs) have increasingly been advocated in recent decades. Gap analysis has been useful to evaluate the sufficiency and performance of CAs. Researchers often identify putative gaps in the protection of biodiversity in CA networks, drawing on evidence from species occurrence patterns (i.e., representation), yet the effect on the gap analyses of the spatial configuration of CAs is poorly understood. Focusing on two large, charismatic carnivores of western Asia, Persian leopard and Asiatic cheetah, we used species distribution models (SDMs) to map potentially suitable habitats throughout the region. We calculated species representation for four categories of CAs within the conservation network in Iran and used a new application of graph theory to include their spatial configuration into our gap analysis. We then regressed species representation against spatial configuration to provide more insights into the performance of different categories of CAs. Results showed that the existing CA network conserves only 32% of the suitable habitats for the two species. Leveraging spatial configuration of the conservation areas into the gap analysis, however, revealed that the recently-established less strictly CAs disproportionately provide a higher contribution to the collective effectiveness of the entire conservation network. We introduce network bias as a new concept in reserve design and argue that incorporating spatial configuration into CA gap analysis improves the ability to evaluate the effectiveness of reserve network designs, and is an important decision support tool for integrated conservation planning.