Landscape connectivity for biodiversity conservation: a mammal-based multi-species corridor approach for the Eden to Addo corridor initiative, South Africa

Abstract Biodiversity conservation is increasingly dependent on maintaining landscape connectivity, particularly in regions facing rapid habitat fragmentation due to expanding and intensifying urbanisation and agriculture. We applied a structured multi-species framework to model ecological connectivity between three mega-reserves ( Addo Elephant National Park, Baviaanskloof Mega-Reserve, Garden Route National Park) in South Africa, integrating expert-derived resistance surfaces with two widely used modelling approaches: circuit theory and least-cost path analysis. Resistance layers were parameterised through expert questionnaires for the nine selected species representing a range of ecological roles and requirements, capturing key landscape features influencing mammal mobility. A multi-species connectivity network was generated by integrating Circuitscape and Linkage Mapper outputs. The results identified 40 potential corridors, comprising areas with a low to moderate human footprint, though agriculture and roads remain significant anthropogenic barriers. Strong connectivity potential was observed among all mega-reserves, with neighbouring protected areas frequently acting as stepping stones. While some corridors align with the 2018 National Protected Area Expansion Strategy, others present previously unidentified connectivity pathways. However, significant challenges remain for the establishment and long-term sustainability of these corridors, including landowner participation and financial feasibility. This study provides a structured framework for multi-species corridor planning in South Africa, offering insights for conservation practitioners aiming to enhance landscape connectivity to achieve regional and national biodiversity conservation objectives.