FUNCTIONAL ASSEMBLAGES OF BIRDS IN HETEROGENEOUS LANDSCAPES ALONG AN URBAN-RURAL GRADIENT IN TIRUCHIRAPPALLI, INDIA

摘要

As a result of urbanisation, landscapes and land use patterns are changing the world over. This extreme form of land use alteration has affected species composition and abundance, moulding a few species to dominate the urban environment and a few others to extinction. Urbanisation occurs at different scales and the community composition of species gets affected accordingly. In this paper, we look into species richness and abundance of birds, and their variation along an urban-rural gradient at Tiruchirappalli, India. In Tiruchirappalli, bird species diversity increases from more to less urbanised centres. Though diversity is less in urban areas, the abundance of species occupying these areas is higher. During this study, the maximum recorded birds were omnivores. The most affected species is the House Sparrow, with a few populations residing in the urban environment. Along the urban-rural gradient, farmlands and wetlands are the most preferred landscapes of birds, and conservation measures need tobe oriented in this direction to protect the most vulnerable species. Species diversity in urban areas is significantly contributed to by edge species that occupy the fringes of urban areas. Though urban landscapes are less species rich, they too play asignificant role in biodiversity conservation as they are species abundant zones. City planners and urban foresters need to pay more attention towards preserving habitats not only in urban areas but along the urban fringes, as they provide suitable corridors for various activities of birds and their movement.