Ecology and breeding biology of the Cattle Egret Bubulcus ibis in an industrial area at Vadodara, Gujarat

Abstract

In the present age of industrialization and urbanization certain species of birds have started adapting to the rapid changes brought by us. Looking into the adaptability of some of these birds, a study was conducted on the ecology and breeding biology of Cattle Egret (Bubulcus ibis). The species has been breeding in an industrial area for the past many years. The campus of a multinational company (Asian Brown Boveri - ABB) having huge production plant located in an industrial area at Maneja village, towards southwest part of Vadodara city was chosen for the study. The campus of the company is spread over an area of 105 acres and has good amount of cultivated vegetation or green belt. The present study was carried out for two consecutive years (2004 & 2005) during the months of April to July, i.e., during the breeding season of Cattle Egrets. The trees selected for nesting were Mimusops ellengi and Lagerstroemia sp. The colony was monospecific with 159 nests. All these nests were simple platform nests. Of all the nests, 13 nests were accessible, for which various parameters like nest size, nest thickness, its distance from the main trunk and distance from the ground were measured. Placement of the nest was observed for almost all the nests. The egg length, egg breadth, fresh egg weight, egg volume and the species specific egg weight constant Kw were noted down. Role of parents during weaning period was observed. Dropped food pellets were analyzed and predation pressure was noted down. © ZOO; 2007.