Assemblage of wetland bird Species in Purbasthali Oxbow Lake, West Bengal, India: Implications for Management

The present study attempts to assess the composition, abundance and diversity of avifauna with respect to their habitat in and around the Purbasthali wetland, based on both primary data collected through the point count method during 2017–2019 and literature data. Among the total 77 species (encompassing 10 orders and 19 families), 39 species are migrants, 18 are rare and 24 species show declining global trend. According to their habitat, they are sub-divided into three categories i.e. waterfowls (live in open water, 20 species), waders (live in bank areas/water edge area, 45 species) and wetland associated (live in nearby trees, 12 species). The Shannon-Wiener Diversity Index (H’) and the Evenness Index (E’) are used to examine the diversity within and between the habitats. The result reveals higher diversity and evenness of the waders in comparison to others. The maximum diversity (H′=3.02) and evenness (E′=0.79) has been recorded for the waders in 2019, whereas the least values (H′=1.02, E′=0.34) have been found in 2016 for the waterfowls. Relative Diversity Index affirms the dominance of the Anatidae family. The birds of the area have now been seriously threatened by human intervention.