Assessing the status of leopard in the Cape Fold Mountains using a Bayesian spatial capture-recapture model in Just Another Gibbs Sampler

Large carnivores are in decline globally. The leopard's (Panthera pardus) adaptability enabled its survival as the last remaining apex predator in the Western Cape, South Africa. Limited suitable habitat and anthropogenic activity imperil the continued survival of leopards, yet density estimates are lacking in the Western Cape, especially across unprotected areas. We employ the flexible modelling environment of Just Another Gibbs Sampler (JAGS) to implement a Bayesian spatial capture-recapture (SCR) model and generate the first density estimate for the leopard population in the Boland Mountain Complex using a dataset collected in 2010-2011. Leopard density was estimated at 1.69/100 km(2) (95% CI = 1.4-1.99) with adult female leopards occurring at a higher density (0.93/100 km(2) [95% CI = 0.64-1.18]) than males (0.76/100 km(2) [95% CI = 0.62-0.90]). Our modelling shows that males have more extensive ranges than females, increasing their susceptibility to anthropogenic threats, which are generally more abundant at the study area's periphery. Tailored conservation efforts are recommended in conjunction with an up-to-date leopard population density reassessment. The JAGS approach to SCR also enabled a detailed investigation of animal distribution and movement, and provides a reliable methodology to monitor population trends.