Herpetofaunal diversity and community structure across different habitats around a Ramsar wetland in Bangladesh

Herpetofaunal diversity in Tanguar haor, a Ramsar listed important freshwater wetlands in Bangladesh, is poorly studied. In this study, the diversity, composition and relative abundance (RA) of herpetofauna in major habitats have been evaluated using visual encounter surveys. A total of 41 species (13 amphibians and 28 reptiles) with 1982 individuals were recorded. Euphlyctis cyanophlyctis (n = 626, RA = 0.348) was the most abundant species among amphibians and Hemidactylus flaviviridis (n = 50, RA = 0.273) among reptiles. Species richness, abundance and diversity differed among habitats. Most amphibian species were found in swamps (12 species), whereas most reptile species were in thicket-shrub habitats (15 species). The maximum observed herpetofaunal species richness and calculated Shannon’s H’ index and Pielou’s evenness were the highest for thicket-shrubs. The Bray-Curtis similarity clustering formed two clusters—between open water and swamp habitats; and between thicket-shrub and agriculture habitats. Twenty-five species were observed in a single habitat and the rest of the species were in more than one habitat. The structural complexity of habitats, dense vegetation, and transitional conditions likely provide optimal shelter, breeding sites, and foraging opportunities for both amphibians and reptiles. The results highlight the importance of maintaining habitat heterogeneity around wetlands to support diverse herpetofaunal communities. To maintain the herpetofaunal diversity observed within the wetland area, continuous monitoring and conservation management activities is clearly essential.