Forest Leopard Study

WCS-Gabon: Forest  Leopard  Study

Forest leopards have never been systematically surveyed in African forests, in spite of their potentially vital ecological role as the sole large mammalian predator in these habitats. The most common techniques for assessing relative abundances of forest mammals are difficult to employ for the surveillance of the secretive leopard. As a result, baseline knowledge of leopard ecology and responses to human disturbance in African forests remain largely unknown.

This gap, combined with the more recent reports on local extinctions in heavily hunted areas, precipitated the initiation of a Forest Leopard Study by the Wildlife Conservation Society (WCS) in Gabon in 2000. The goal of the study is to accurately establish the status of leopards throughout the African rain forest belt for the first time. 

Threats
Forest leopard populations are likely to be negatively affected by a variety of factors, including prey depletion, direct hunting, and habitat conversion. It is difficult, however, to determine particular causes of leopard decline in any given area. Recent studies on tigers in India have shown that prey depletion can be the most important factor in reducing populations of large cats. Indeed, in areas of Central and West Africa where hunting for bushmeat is intense, leopard numbers appear to be rapidly declining. For example, although leopards once ranged throughout Nigeria, surveys conducted in the southeastern part of the country conducted in 1997, revealed leopard signs in only 2 of 47 forest patches. Researchers report a similar situation in the rain forests of southern Cameroon, where leopards have disappeared from a number of protected areas within the past ten years.

WCS Activities

We currently estimate leopard population densities in several protected and hunting areas, applying scientific models applied to camera-trap data. At the same time, we estimate the relative abundance of principal prey species using photographic rate indices - the number of days before a camera obtains a photograph of the species, summed against all cameras in the study. Finally, we study leopard prey composition in all sites through scat analysis.

Comparisons of the results from the protected versus the hunted areas will allow us to document how the off-take of bushmeat from an area affects leopard population densities and the relative abundance of principal prey species, and to understand how leopards cope with the competition for prey with human hunters.

Our principal hypotheses include: 1) that leopards hunt for smaller prey species where medium-sized prey are scarce due to human off-take (functional response); and 2) that leopard population density decreases with increasing levels of hunting for bushmeat, as a result of a scarcity of prey (numerical response).

Important Next Steps
Our results will significantly advance our ability to extrapolate densities of leopards across larger areas, as populations are affected by bushmeat consumption, proximity of habitats to human settlement, human population density, or other parameters. Ultimately, the overall status of leopards in Gabon will be assessed by integrating information on vegetation types, the degree of human-induced disturbance, and known levels of bushmeat off-take throughout the country. Comprehensive market and household surveys on bushmeat consumption over the past three years have advanced our knowledge of the latter statistic. Using our data on population densities in different areas with varying hunting levels and forest types, a resulting population density will be assigned to territories of 20 square km, with the aim of deriving estimates of leopard numbers for the whole country.

Download our handbook on leopard survey and monitoring techniques at:http://savingwildplaces.com/media/file/low-leopard.pdf