Study on avifaunal diversity from three different regions of North Bengal, India

A rapid avifaunal diversity assessment was carried out at three different locations of north Bengal viz. Gorumara National Park (GNP), Buxa Tiger Reserve (BTR) (Jayanti/Jainty range) and Rasik Beel Wetland Complex (RBWC) during 2nd November and 14th November 2008. A total of 117 bird species belonging to 42 families were recorded during the present short span study. The highest bird diversity was recorded in GNP with 87 bird species, followed by RBWC (75) and BTR (68). The transition zones between GNP and BTR, BTR and RBWC and GNP and RBWC were represented by 51, 41 and 57 common bird species, respectively. A total of 36 bird species were recorded in all three study sites. This diverse distribution of bird species was reflected in the study of diversity indices where the highest Shannon–Wiener diversity index score of 3.86 was recorded from GNP followed by RBWC (3.64) and BTR (2.84). The similar trend was also observed for Simpson’s Dominance Index, Pielou’s Evenness Index and Margalef’s Richness Index. Consequently in the dendrogram analysis, we found that GNP and RBWC were much closer to each other while BTR remained distantly located form this cluster. The present study recorded two birds viz. Black-naped oriole (Oriolus chinensis) and Marshall’s iora (Aegithina nigrolutea) previously not reported from the present study location. Like other protected areas of the country the present study location is also facing conservation challenges and more intensive studies will certainly reveal the impact of anthropogenic alteration of the habitats in and around the present study location along with the enrichment of knowledge for the avifaunal diversity.