Counting the spots: The use of a spatially explicit capture–recapture technique and <scp>GPS</scp> data to estimate leopard (<i>Panthera pardus</i>) density in the Eastern and Western Cape, South Africa

Abstract

Abstract Estimating species population density directly contributes to the conservation of species. As keystone species, carnivores are important to conserve; however, estimating density of wide‐ranging, elusive and solitary carnivores has proven difficult. The leopard ( Panthera pardus ) is the last large free‐roaming top carnivore in South Africa, and no formal density study had been conducted across the Eastern and Western Cape. We estimated leopard density and abundance using GPS data from 21 collared leopards and a spatially explicit capture–mark–recapture ( SECR ) method with camera trap survey data. Four regional sites were surveyed using 173 camera trap locations over 15,390 camera trap days, capturing 740 leopard images of which 77 individuals were identified. SECR averaged 0.95 leopards/100 km 2 and the two GPS methods averaged 1 and 1.11 leopards/100 km 2 . Based on predicted available leopard habitat for the region, leopard abundance was estimated between 467 (±112.8) and 553 (±168.8) in the Western Cape and between 365 (±93.2) and 430 (±139.9) in the Eastern Cape. Discrepancies in density estimates can be complex stemming from biological behaviour, anthropogenic factors and prey density. However, our estimates appear to show relatively little variation, suggesting that SECR methods and GPS data capture the population density estimates of the species well.