Abstract
Waterbirds play a vital role in balancing aquatic ecosystems. Regular studies of their conservation status are crucial. Three major wetlands: Karnali River, Geruwa River, and Badhaiya Lake were surveyed from 2011 – 2016 and 2021 to assess the species and sites’ long-term status. We counted all water birds in these areas using the point count method in Badhaiya Lake and the Line transect method for river tran-sects of Karnali and Geruwa. Shannon-Weiner diversity index, Margalef richness index, and Pilou evenness index were calculated for each year and site to understand diversity and richness patterns over time and space. A total of 86 species were observed with an average number of species of 1027.02 per year. The relative abundance of the species showed fluctuations over the study period. The most abundant species was the Ruddy Shelduck (744.91 individuals/year), followed by the Lesser Whistling Duck (494.25). While the Ruddy Shelduck population increased, the Black Stork and Asian Wolly Neck species declined. Among the sites, Badhaiya Lake exhibited the highest Margalef richness index, Pilou evenness index, and Shannon-Weiner diversity index compared to Karnali and Geruwa Rivers. Due to its species richness and waterbird abundance, continuous monitoring and conservation efforts should be prioritized for the site.