Environmental and anthropogenic drivers of African leopard Panthera pardus population density

Globally three quarters of large terrestrial mammalian predators are in decline and many populations are data deficient, including those of African leopards across much of their range. Here we assess the drivers of decline African leopard populations in 16 camera trap surveys covering a total area of 15,120 km(2), across a gradient of anthropogenic impact, management and geography, in protected areas across the Zimbabwean component of the Kavango-Zambezi (KAZA) Transfrontier Conservation Area. Population density was calculated using spatially explicit mark-recapture estimators and Generalised Additive Models (GAM) were used to assess factors affecting population density. Density estimates ranged from 0.7 to 12.2 (mean 2.9 +/- 2.7) leopards/100km(2). Leopard density was higher in wooded sites and rugged terrain but negatively affected by human factors including human appropriation of net primary productivity (HANPP), trophy hunting risk and bush-meat poaching. High lion densities (> 6.0 lions/ 100km(2)) negatively affected leopard density. Annual rainfall over a gradient of ~300 mm across survey sites was not influential in predicting population density. Previous assessments of the drivers of declining leopard population density (CITES 1988), asserting that leopard densities can be predicted by annual rainfall and are unaffected by human disturbance in unmodified habitat are not supported by our findings. We recommend that the 1988 assessment, used to manage CITES leopard trophy hunting export quotas since the late 1980s, should be reviewed.