Dietary niche breadth and overlap of four sympatric southern African myrmecophagous mammal species, as inferred from the literature

Darren W Pietersen, Mark P Robertson — Thu, 07 Sep 2023 00:00:00 +0000

Five myrmecophagous mammal species occur sympatrically over large parts of southern Africa. Of these, the diets of four species have been studied in sufficient detail to facilitate interspecific comparisons. The diets of the aardvark Orycteropus afer, aardwolf Proteles cristatus, bat-eared fox Otocyon megalotis and Temminck’s pangolin Smutsia temminckii were compared based on the overall prey categories utilised and the proportion of each prey category in their diets, while Meller’s mongoose Rhynchogale melleri had too few data to be assessed. Bat-eared fox fed on the greatest number of prey categories (n = 116) and had the greatest dietary niche breadth (4.71), while aardwolf utilised the fewest prey categories (n = 28) and had the lowest dietary niche breadth (1.19) when analysing the proportion of each prey category in the diet at the genus level. Temminck’s pangolin was the only species that was observed to feed exclusively on ants and termites. The diets of Temminck’s pangolin and aardvark showed a moderate degree of overlap (dietary niche breadth 0.49–0.57), but overlap was low between all other species pairs (0.01–0.26) when analysing the proportion of each prey item in the diet at the genus level. The results suggest that these myrmecophages have low to moderate dietary overlap, which combined with the high abundance of ants and termites and differences in their feeding ecologies, likely reduces interspecific competition.

Anuran diversity in a West African Valley

Thu, 07 Sep 2023 00:00:00 +0000

Anurans are subject to strong anthropic pressures in Benin, as in most of the West African countries, due to their socio-economic and environmental importance. To protect these organisms and to gather basic knowledge, an anuran biodiversity study was conducted in the lower Ouémé Valley in Benin. Anurans were inventoried in five types of habitats in four municipalities. Visual and auditory detections were used to observe, count and/or catch specimens at night, aided by headlamps. Five physico-chemical parameters were simultaneously measured. Species were determined using identification keys, authenticated by specialists at the Leibniz Institute for Evolution and Biodiversity Science’s Museum für Naturkunde, Berlin. Our study observed 28 species, with several species living in degraded forests. Afrixalus fulvovittatus (Cope 1860) was recorded for the first time in Benin; and the taxonomic status of three anuran species, Sclerophrys sp., Hyperolius sp. and Arthroleptis sp., still require clarification. Among the species inventoried, Hyperolius torrentis is listed as vulnerable by the IUCN category. Anuran distribution was closely related to ambient air temperature and soil humidity, with abundance increasing with low ambient air temperature and high soil humidity. We note the importance of protecting these organisms’ habitats in order to maintain the optimal environment for their growth and breeding.

African Zoology

Dietary niche breadth and overlap of four sympatric southern African myrmecophagous mammal species, as inferred from the literature

Anuran diversity in a West African Valley