Biodiversity hotspot revisited: reptile and amphibian assemblages of the Uluguru Mountain Forest Reserves, south-eastern Tanzania

Abstract

ABSTRACT Although the knowledge about the Tanzanian reptiles and amphibians has drastically increased in recent years, the knowledge on the amphibian and reptile fauna of the remaining forest reserves of the Uluguru Mountains (UMs) is only partially known. Amphibians and reptiles were studied in 17 forest reserves and sampled using diurnal and nocturnal time-constrained visual encounter surveys, acoustic surveys and opportunistic searches. A total of 51 quadrats of 25 × 25 m were randomly established on the forest floor, totalling 459 person-hours of sampling effort. Overall, 54 herpetofauna species (27 amphibian and 27 reptile species) were recorded from the area, including two anurans and seven reptile species, which are new records for the region. The estimated Chao1 species richness for the study region was 51 for amphibians and 76 for reptiles. Amphibian and reptile species composition did not differ significantly across the forest reserves, but similarities in species composition of different levels were evident across the reserves. For both communities, α-diversity and relative abundance did not vary significantly across the reserves. Based on multiple regression analyses, leaf-litter anuran species richness was positively influenced by percentage canopy cover, whereas abundance was negatively influenced by total fragment size. Partial correlations showed that variation in leaf-litter anuran abundance was explained by relative humidity, percentage canopy cover and soil moisture, while controlling for altitude. Percentage canopy cover was also the best predictor of species richness of leaf-litter anurans. Overall, these findings highlight the importance of protecting the UMs forest reserves for herpetofauna conservation.