Herpetofaunal diversity and community structure in the Murchison Falls - Albert Delta Ramsar site, Uganda

Abstract

1. The area of the Murchison Falls-Albert Delta is among the most important for conservation in East Africa due to the high species richness, and the presence of several endemic species of conservation concern. 2. Here, we report a study on the diversity patterns and community structure of the herpetofauna of this area. 3. Field studies were conducted in the Albert Nile Delta Ramsar site between 1st October 2017 and 9th September 2018. The data collection relied on Visual Encounter Surveys (VES), pitfall trapping, and dip netting. Descriptive statistics, i.e. species numbers in each transect were used as a measure of the present biodiversity, whereas Chao1 and Chao species estimator algorithms were used to predict the potential number of species found in each site/habitat. 4. A total of 898 individuals representing 25 reptile species belonging to four orders, 15 families, and 20 genera were recorded during the 12 months of surveys. 5. The data shows some non-random spatial and temporal patterns whereby there is a cyclic reptilian diversity peaking during the December-March and again towards June-August-September which are peaks of the dry season. 6. The most frequently encountered species were Varanus niloticus, Crocodylus niloticus, Agama agama, Trachylepis maculilabris, and Lygodactylus guttularis, which accounted for almost 90% of all recorded individuals. 7. A total of 27 amphibian species, belonging to nine families and 10 genera were recorded during the period of the survey. The diversity and abundance graphs would indicate amphibians having bimodal peaks (September-December, and March-May). The diversity seemed to dip during the dry season months – which is the opposite case for reptiles.

Keywords

• Biodiversity, herpetofauna, diversity, Albert Delta, Murchison, Falls Red List