1,115 publications found
Sort by
Anuran diversity in a West African Valley

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.

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

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.

Open Access
Endohelminth parasites of male and female tigerfish, Hydrocynus vittatus (Castelnau, 1861), from the Sanyati basin in Lake Kariba

Tigerfish (Hydrocynus vittatus Castelnau, 1861) is of considerable importance in both the commercial and recreational fishery activities of Lake Kariba. In our previous paper (Mabika et al. 2019) we provided information on the seasonal occurrence of metazoan parasites of H. vittatus. This communication provides endohelminth infection statistics of male and female H. vittatus across two seasons not previously included. A total of 80 H. vittatus individuals consisting of 56 females and 24 males were examined for endohelminth parasites during the period October 2014–July 2015 in the Sanyati basin, Lake Kariba. Parasites were recovered from the abdominal cavity, mesentery and intestines. Most of the parasites were harboured in the abdominal cavity in both sexes. Parasite infection was more prevalent during the dry season in comparison to the rainy season for both sexes. Contracaecum larval infection was significantly higher in female (84%) than in male tigerfish (24%), whereas larval cestode infections were significantly higher in male tigerfish (59%) than female fish (16%). The mean condition factor of the male tigerfish (1.68) was not significantly higher than that of the female (1.64). The results of the study indicate that female tigerfish were more suitable hosts to Contracaecum larval infection than the male fish. Further parasitological and histopathological research on tigerfish is recommended to contribute to knowledge on endohelminth diversity and conservation.

Testing the efficacy of bat monitoring methods for identification and species surveys in KwaZulu-Natal province, South Africa

Multi-method sampling approaches are becoming increasingly popular for investigating species occurrence at specific sites, as there is a need to accurately monitor species with limited time and resources. In this study, a multi-method comparative approach was used to survey bat species in the foothills of the Drakensberg Mountain range in KwaZulu-Natal province, South Africa. We used historical museum records and species distribution modelling (SDM) to predict which species would likely occur in our study area. We then compared physical capture (by deploying mist nets) with acoustic surveys (using an Anabat bat detector) to assess the bat species assemblages present. Species distribution models predicted eight bat species to occur from the historical checklist of 28 species recorded in the broader region, as no museum records existed for the specific study area. Species detection by acoustic data yielded the highest number of detected species ( n = 11) while active trapping yielded nine species from 54 individuals of four families, namely, Laephotis botswanae, L. capensis, Myotis tricolor, Pipistrellus hesperidus, Rhinolophus clivosus, and Tadarida aegyptiaca with molecular confirmation required for Miniopterus fraterculus, R. darlingi and R. swinnyi. These complementary sampling methods may be necessary for accommodating the limitations of each individual method for a more inclusive assessment of bat species richness in a targeted landscape. The present study could be used as a model approach to assess the biodiversity and demographics of other taxa and in other habitats.