Assessing the wildlife trade in western Africa through the prism of functional diversity: a comparative study between two types of wildlife markets from southern Benin

Abstract

Abstract We tackle the potential impact of bushmeat markets (BM) and traditional medicine markets (TMM) on the functional diversity of mammalian communities in southern Benin. A hybrid approach combining direct observations, DNA-typing and questionnaires allowed us to identify 94 species-level taxa across 11 mammalian orders, the greatest ever reported numbers for African wildlife markets. TMM sold species of high conservation concern or regulated by international conventions and recruited across all the taxonomic orders and bioclimatic zones. BM were taxonomically (25 species), bioclimatically and functionally 100% nested within TMM. However, functional diversity was high in both markets, which sampled across nine diet specializations and five main ecological functions, including seed dispersion (mostly frugivores, folivores and omnivores), prey regulation (mostly carnivores and invertivores), browsing (mostly folivores), grazing (omnivores) and fertilization (nectarivores). TMM sampled species with the greatest body weights and generation lengths, and smallest litter sizes, including large herbivores and keystone predators. For these reasons, they likely jeopardize the regulatory, structural and production functions of the sourced ecosystems. BM, despite their local sourcing, sampled across a non-selective taxonomic and functional spectrum and as such, also represent a significant threat to ecosystem functioning in southern Benin. The functional database that we provide can serve as a starting point to pursue the quantification of functional diversity in African mammals and further investigate the impact of wildlife markets on ecosystem functioning in tropical Africa. Overall, long-term surveys of BM and TMM are needed to accurately quantify the threat they constitute to mammalian biodiversity and the sustainability of ecosystem services.