Mammals of the Eastern Niger Delta (Rivers and Bayelsa States, Nigeria): An environment affected by a gas-pipeline

A study of the ecology and distribution of the mammal fauna in the Niger De lta region of southeastern Nigeria (Port Harcourt territory, Rivers, and Ba yelsa States) was conducted as part of a larger environmental project with gas and oil production industries. Mammalian biodiversity at ten study loca lities was assessed by means of standardized transects, mammal trapping, in terviews, sightings, and other signs of presence. Twenty-six species were r ecorded for the first time in the study area and six species recently found by previous authors, were confirmed. The study localities varied significa ntly in terms of both abundance and species diversity, dominance and evenne ss indices. Generally these differences can be attributed to differences in environmental characteristics. Primary and secondary rainforest, both dry and swamp types, housed significantly more species than mangroves. In terms of conservation, we found the mammal fauna of this area remarkably importa nt. According to recent IUCN criteria, the presence of two Critically Endan gered (CR) species (Panthera pardus, Tragelaphus spekii), and five Endanger ed (EN) species (Potamogale velox, Cercopithecus sclateri, Cercocebus torqu atus, Procolobus badius epieni, Trichechus senegalensis) was also noteworth y.