To track or to call: comparing methods for estimating population abundance of African lions Panthera leo in Kafue National Park

Abstract

The wide-ranging behaviour of large carnivores and low densities at which they occur make direct population surveys of these species expensive and time consuming, and consequently indirect methods are widely used. We compared the accuracy, precision and cost of two methods commonly used to survey African lions, namely call-up surveys and track-count surveys. Surveys were performed in the 11,000 km2 northern sector of Zambia’s Kafue National Park (Kafue), an area for which no previous empirical lion population data are available. We estimate lion abundance of 200 individuals over 1 year of age in northern Kafue, at a density of 1.83 lions 100 km−2. We used GPS collars and regular observations of lions to establish a reference population in an Intensive Study Site for comparison with survey results. Both survey methods produced accurate results, though precision was higher for call-up surveys, despite lower costs. Stratification of the study area did not improve the survey estimates. We recommend call-up surveys as the most appropriate method for surveying lions in Kafue and similar large protected areas, and suggest standardisation of survey equipment and protocols.