Priority areas identified through spatial habitat suitability index and network analysis: Wild boar populations as proxies for tigers in and around the Hupingshan and Houhe National Nature Reserves

Abstract

The decline and fragmentation of habitats areas are two main factors that lead to the reduction of biodiversity in landscape ecosystems. As a kind of large carnivores, South China tiger (Panthera tigris amoyensis) is one of the most endangered tiger subspecies and considered to be extinct in the wild. The Chinese government has intended to release a certain number of tigers into two of their historically habitats areas, Hupingshan–Houhe national nature reserves (NNR) in central–south China that provides suitable habitats for P. tigris. Because wild boar (Sus scrofa) is a prey of P. tigris, spatially characterizing the populations of the prey and its habitats is critical for the success of habituating the tigers to the areas. Although there has been effort made to protect the habitats of wild boar, there have been no report that deal with investigation and analysis of the habitat suitability and potential for wild boar, especially in terms of landscape connectivity. Here we present the novel integration of the habitat suitability index (HSI) and graph–based network to identify the priority areas for wild boar dispersal in and around the NNR. In addition, a novel method to identify the proper connectivity distance to avoid excessive connectivity when the field data are essentially non-existent. Results showed that in summer and winter, the potential habitat areas were 6848–10,245 and 5984–10,152 km2, respectively. The total area of the priority patches was 1590 km2, approximately occupying 16% of the suitable habitat area. Our study indicated that the novel integration of the HSI and network analysis led to an effective approach to spatially characterize priority patches to support decision-making for landscape planning. The results shown here also have implications for future efforts for habituating large carnivores into their historical habitat regions.