Population size, density, and ranging behaviour in a key leopard population in the Western Cape, South Africa

Abstract

Globally, leopards are the most widespread large felid. However, mounting anthropogenic threats are rapidly reducing viable leopard populations and their range. Despite the clear pressures facing this species, there is a dearth of robust and reliable population and density estimates for leopards across their range, which is particularly important in landscapes that consist of protected and non-protected areas. We conducted a camera trapping survey between 2017 and 2018 in the Western Cape, South Africa to estimate the occupancy, density, and population size of a leopard population. Leopards were recorded at 95% of camera trapping sites, which resulted in a high occupancy that showed no significant variation between seasons, habitat types, or along an altitudinal gradient. Our results indicated a low leopard density in the study area, with an estimated 1.53 leopards/100 km 2 in summer and 1.62 leopards/100 km 2 in winter. Mean leopard population size was therefore estimated at 107 and 113 individuals in the winter and summer respectively. Leopard activity centres for female ranges were centred in the core study area and could be predicted with good certainty, while males appeared to move out of the study area during winter which resulted in a higher uncertainty in locations of activity centres. Interestingly, livestock depredation events in the surrounding farmlands were significantly higher in winter, which coincides with male leopards moving outside the core protected area into the surrounding farmlands. To reduce livestock losses and retaliatory leopard killings, we suggest that human-carnivore conflict mitigation measures be intensely monitored during the winter months in the study area. We also suggest that future leopard conservation efforts should focus on privately-owned land as these non-protected areas contain the majority of the remaining suitable leopard habitat and may provide important dispersal corridors and buffer zones on which the long-term sustainability of leopard populations depends.

The Recolonisation of the Piketberg Leopard Population: A Model for Human–Wildlife Coexistence in a Changing Landscape

“…Therefore, understanding factors driving density can provide more insight into population dynamics. Generally, leopard density estimates have been undertaken in protected areas [16,36,42,43]. While protected areas are crucial for carnivore conservation, most leopard habitats in South Africa exist outside protected areas [8,40,44].…”

“…Using SECR, other studies in the Eastern and Western Cape report estimated ranges of leopard density from ~0.17 to 1.8 leopards per 100 km 2 [10,11,16] (Supplementary Materials S7). Therefore, the Piketberg appears to host a leopard population with some of the highest reported leopard density estimates in the region (~1.8, CI 1.3-2.4 leopards per 100 km 2 ).…”

“…For example, leopard population estimates for the Eastern and Western Cape provinces in South Africa were 467 and 553 adult leopards respectively [11,15]. Within different regions of the two provinces density estimate vary from 0.17 to 1.89 leopards/100 km 2 [10,11,16,17]. However, density estimates alone fail to provide insight into the health and sustainability of metapopulation dynamics across a heterogeneous landscape that encompasses varying levels of anthropogenic impacts and local habitat conditions.…”