The waterbuck (Kobus ellipsiprymnus), though widespread throughout Africa, is suspected to be declining overall. Data on population numbers and structure are lacking for many parts of its range, especially in West Africa, where the subspecies defassa is found. The aim of the present study was to evaluate the abundance, distribution and attributes of waterbuck populations from the Nazinga Forest Reserve, southern Burkina Faso. We investigated waterbuck population trends in the park using transect data collected in 1985–2019. For the more detailed analyses of population structure and distribution of the animals, we used census data gathered during 2019. Most animals were adults (46.6%), and the sex ratio was heavily skewed towards females (5:1). Most animals were concentrated along the larger rivers. There was no influence of poacher activity on waterbuck distribution. In the long term (1985–2019), the population dynamics of waterbuck can be roughly divided into two main periods: a phase of population increase from 1985 to 2005, and one of ongoing population collapse from 2007 to 2019. Although the declining population trend was obvious, coefficients of determination were low indicating that the years explained poorly the number of individuals and the number of sightings obtained. Waterbuck numbers in the Nazinga Forest Reserve are declining, but we found no single reason to explain this trend. It is likely that a combination of factors, including global warming (increased aridity) and illegal activities such as poaching, is responsible. Because there are probably multiple reasons for the observed waterbuck population decline in our study area, we suggest that a multifaceted approach should be adopted in order to enhance the conservation status of the local waterbuck populations.

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Long‐term changes in population size and the age structure and sex ratio of waterbuck in a Sudanian savannah of Burkina Faso

Apparent density [determined as kilometric index of abundance (KIA), by direct sightings and by droppings along line transects] and habitat use of some species of carnivore mammals were studied in two protected areas of Burkina Faso (Comoe-Leraba and Nazinga). Despite the fact that the dataset was collected throughout several years and with a very high field effort, the amount of data collected was relatively small, and confined just to a few species. There was no effect of the year on the average KIA estimates of the carnivores at this study area, and data from direct sightings along transects estimated lower densities than those coming from droppings collected along the same transects. In terms of habitat type, shrub savannah represented the best habitat type for carnivores, despite being relatively scarcely available along the line transects when compared with woody savannah (especially for Canis adustus and Civettictis civetta).

Ismael Tou

Papers

Preliminary data on density and habitat of carnivores in two protected areas of Burkina Faso (West Africa)