AVIFAUNAL DIVERSITY IN THE LOWER DAMODAR RIVER BASIN OF HOWRAH DISTRICT, WEST BENGAL, INDIA

Background: Lower Damodar river basin is a densely populated area in the Howrah district, West Bengal state, India. There are incidences of water overflow in the region every year during monsoon. The area is chiefly dominated by agroecosystems and aquatic bodies of varied dimension. The region possesses rich diversity of birds fauna which is yet to be documented till date and thus need to be surveyed.

Aim: Prepare a checklist of the avifaunal diversity alongwith their habitat strata and feeding guilds.

Materials and methods: The avifaunal diversity using suitable birds count method in a small patch of 30 sq.km. area located in the lower Damodar river basin was documented.

Results and Discussion: 574 individuals of 62 species of birds belonging to 15 orders and 32 families were documented from the area. Order Passeriformes represented by 14 families, were the most abundant in the area followed by Pelecaniformes and Columbiformes. 10 different habitat types and 8 feeding guilds for the birds were identified in the region. The bird community in the region is dominated by insectivore (32%) followed by carnivore (14%), omnivore (13%), granivore and nectarivore (10% each), frugivore (9%), scavenger (7%) and piscivore (5%). Analysis of variance between the group means of the birds belonging to different habitat strata shows significant difference.

Conclusion: Biodiversity indices shows lesser dominance, good evenness and richness of bird species in the area. Spread of the human settlement across the pristine ecosystem, occasional hunting along with non-judicious uses of pesticides in the agricultural fields are the major threats to the bird diversity in the region that needs further detailed study.