Measuring species diversity while counting large mammals: comparison of methods using species-accumulation curves

With a growing need for wildlife conservation and management in the communal lands of Africa, comprehensive ecological monitoring tools need to be developed and evaluated. While wildlife census methods are often compared in terms of precision and accuracy to estimate the population size of various target species, little attention has been paid to the measure of species diversity in mammal communities. A combined measure of abundance and community composition is, however, a crucial source of information in determining conservation priorities and to evaluate the ecosystem responses to management activities. In this study, we present five census methods of large to medium-sized mammals and compare their efficacy in measuring species diversity. A species accumulation curve analysis is used with a predictive model to estimate the local species richness, the level of completeness of our censuses as well as the effort required to carry out a census. Advantages and limits of each method are discussed through comparison of their respective measure of species richness and their species accumulation rate. Results illustrate a large difference between methods in the ability for species detection, with censuses completed by bicycle offering the best option within the context of a unprotected area.