Assessment of Amphibian Populations in Freshwater Ecosystems of Enugu State

Amphibians serve as sensitive biological indicators of freshwater ecosystem health, and their populations have shown global declines linked to habitat degradation, pollution, and disease. In Nigeria's South East geopolitical zone, particularly in Enugu State, amphibian population assessments are almost entirely absent from the scientific literature. This study investigates the species composition, abundance, and habitat preferences of amphibian populations in five freshwater sites across Enugu State. Sites were selected to represent a gradient of human disturbance, from near-pristine forest streams to peri-urban drainage systems. Standard Visual Encounter Surveys combined with acoustic monitoring were used to record anuran species. A total of 28 amphibian species were identified, representing 6 families, with the highest species richness observed at the least disturbed forested stream sites. Several species with restricted distributions, including Cardioglossa gracilis and Phrynobatrachus calcaratus, were recorded at a single location, highlighting the site's conservation value. Agricultural runoff, associated with high nitrogen and phosphorus levels measured in water samples, was significantly correlated with reduced amphibian diversity at impacted sites. The study recommends buffer zone vegetation restoration along stream margins, restrictions on agrochemical use in catchment areas, and the inclusion of amphibians in state biodiversity monitoring programs. These findings provide the first systematic amphibian inventory for Enugu State. Keywords: amphibians, freshwater ecology, Enugu State, South East Nigeria, biodiversity monitoring