Using heronry birds to monitor urbanization impacts: a case study of painted stork Mycteria leucocephala nesting in the Delhi Zoo, India.

Although urbanization is a frequently cited cause of biodiversity loss (Czech and Krausman 1997) our understanding about urban ecology is severely limited (Marzluff et al. 2001). Birds are popular bio-indicators of environmental change because they are ecologically versatile, their populations as well as select fitness parameters can be conveniently monitored, often with the voluntary involvement of local nature enthusiasts across large geographical scales, and their presence/absence in a particular area is consequential (Bibby et al. 1992; Urfi 2004). In India, while several studies have focused on changes in bird populations and distributions in natural habitats (Urfi et al. 2005), very few have actually attempted to study either the impacts of urbanization on birds or how different species have adjusted to environmental change. However, many Indian cities offer foraging and nesting habitat for birds, especially colonial waterbirds such as stork, ibis, spoonbill, heron, egret, cormorant, and spoonbill. Some notable examples in this regard are Piele Gardens in Bhavnagar city (Parasharya and Naik 1990), Karanji Tank in Mysore (Jamgaonkar et al. 1994) and the National Zoological Park (hence forth Delhi Zoo) in India's capital city New Delhi (Urfi 1997). In this article, I focus on the opportunities for meaningful ecological research offered by the wild waterbirds nesting in the Delhi Zoo premises and discuss the significance for initiating novel, long term conservation monitoring programs, involving volunteers and bird watchers, to create data bases that will be useful for understanding urbanization and climate change impacts on biodiversity.