Diversity, Species Richness, and Community Composition of Wetland Birds in the Lowlands of Western Nepal

Wetlands serve as crucial habitats for diverse bird species, playing a vital role in maintaining the ecosystem. Geographical location, climate, hydrology, and vegetation composition of wetlands determine the diversity of birds. This study investigated species richness, seasonal diversity, and composition of wetland birds in three prominent water bodies of western Nepal, namely Ghodaghodi, Rani, and Jokhar lakes, from 2021 to 2022 in summer and winter using the point count method. We observed 59 wetland bird species across three wetlands, where both the richness and diversity were significantly higher in the winter. Paired t-tests revealed significant seasonal differences (p < 0.001) in diversity, species richness, and abundance at both Ghodaghodi and Rani lakes. The highest species richness was observed at Ghodaghodi (n = 58), reflecting its significance as a vital bird habitat. In contrast, diversity was higher in Rani Lake during both seasons (Winter H = 2.98, Summer H = 2.79). NMDS followed by ANISOM test also showed that bird community structure varies across lakes and seasons. Indicator species analysis showed that out of 59 species, 26 species are associated with one or different sites, whereas 18 of them are associated with the summer or winter season. We observed the Anatidae family with the highest relative diversity (RDI = 28.81%) and reported 1 globally vulnerable species and 7 globally near-threatened species. While in Jokhar Lake, the abundance does not vary between the seasons. This study revealed substantial differences in bird species across seasons and lakes showing that each wetland offers a distinct ecological niche for bird species. The findings reinstate the importance of these wetlands as crucial habitats for the diversity of birds and species composition. This research contributes to the conservation and management of these ecosystems, aiding the protection of wetland birds in Nepal.