Assessing and understanding diversity and foraging guilds of bird community structure in Gautam Buddha Wildlife Sanctuary, Bihar and Jharkhand, India

This study was conducted between June 2017 and December 2018 to assess the bird community structure, diversity, feeding guilds, and the residential status of birds in Gautam Buddha Wildlife Sanctuary (GBWS). Avian diversity and guild organization in five different habitat types were classified according to the forest type present in the landscape. The results indicated a total of 99 avifauna that belongs to 48 families, distributed in 16 orders. Among the 99 species, 77 were residents, 17 were winter visitors, four were summer visitors, and only one was a passage migrant. Based on the feeding guild evaluation, the majority were insectivorous (47%), followed by omnivorous (24%), carnivorous (14%), granivorous (8%), frugivorous (4%), insectivorous (1%), and piscivorous (1%). The scrubland, among other forest types, represented the highest diversity value for the Shannon-Weiner diversity index (3.2), evenness was recorded highest in riverine habitat (0.63), whereas utmost Simpson’s dominance (0.98) and Fisher’s index value (41) were in human settlement. These findings of our study illustrate the outstanding potential of GBWS as an important protected site for mixed bird diversity and specific feeding guilds, precisely in terms of the insectivorous and omnivorous communities. Hence, the study outcomes set a notable landmark for understanding birds and their habitats.