Herpetofauna community diversity and composition of a changing coastal wetland in Ghana

Abstract

Despite concern about the negative effects of tropical wetland loss and degradation on biodiversity, data on impacts on amphibians and reptiles, remain scarce. Here, we assessed the herpetofauna at the Muni-Pomadze ramsar site for the first time in 14 years and report on the changes in diversity and composition at the coastal wetland. The methodology involved pitfall trapping, refuge examination and acoustic searches in the forest and grassland/ thickets habitats, as well as interviews of a cross-section of local inhabitants. Overall, 39 herpetofauna species were recorded at the study area. These comprised 19 amphibian species belonging to six families (Bufonidae, Ranidae, Hemisotidae, Hyperoliidae, Arthroleptidae and Petropedetidae), and 20 reptile species of nine families. The reptiles consisted of four lizard families (Agamidae, Scincidae, Gekkonidae and Varanidae), four snake families (Boidae, Colubridae, Elapidae and Viperidae) and one chelonian family (Pelome dusidae). Three families, Hemisotidae, Arthroleptidae and Viperidae are first records for the study area. Survey at the site in 1998 recorded 28 species, comprising 15 species of reptiles and 13 species of amphibians. Two families (Microhylidae and Testudinidae) recorded in 1998 were not recorded in the present survey. Although we recorded higher species richness in the present study, there was no significant change in the proportion of savanna and generalist species in the forest because of compensatory dynamics. Given that habitat loss at the patch and landscape levels is the main threat to herpetofauna at the ramsar site, conservation managers should focus on preventing further deforestation, particularly at Yenku Block A Forest Reserve to preserve the herpetofana at the Muni-Pomadze ramsar site.