Where buffalo and cattle meet: Modelling interspecific contact risk using cumulative resistant kernels

28 November 2017

Kaszta, Żaneta; Cushman, Samuel; Sillero-Zubiri, Claudio; Wolff, Eléonore; Marino, Jorgelina

African buffalo the primary source of foot and mouth disease (FMD) infection for livestock in South Africa. Predicting the spatial drivers and patterns of buffalo-cattle contact risk is crucial for developing effective FMD mitigation strategies. Therefore, the goal of this study was to predict fine-scale, seasonal contact risk between cattle and buffaloes straying into communal lands adjacent to Kruger National Park. This study provides the first application of the cumulative resistant kernel method to calculate contact risk between two species. We built resistance surfaces from resource utilization models of buffalo and cattle and calculated the intersection of resistant kernels of the two species. This revealed that the contact risk is influenced by seasonality, water sources and fence strength, and the magnitude of contact risk is largely driven by buffalo and cattle dispersal abilities. The probability of contact was higher in the dry season, with hotspots along a main river and the weakest parts of the perimeter fence. In the wet season, contact risk was more diffuse and less concentrated along the main river and near settlements. The new approach of intersecting cumulative resistant kernels of two species can produce quantitative predictive maps of animals’ contact risk and help identify potential hotspots of disease transmission.