Population Status and Distribution of Cattle Egret (Bubulcus ibis)

Abstract

The research work on“Population status and distribution of Cattle Egret in Kathmandu Valley”was carried out from 2003 to 2006 to estimate population status, distribution pattern of cattle egrets and to identify the tree species preferred for roosting and nesting. Distribution pattern of cattle egret in the valley was determined based on nesting and resting sites. Direct counting method was used to estimate population status. The number of tree species and the number of nest in each tree species was used to identify the tree species preferred for roosting and nesting. A total of1284 nests or breeding pair of cattle egret were found in five nesting sites. The distribution of cattle egret was uneven and clumped which were commonly seen in colonial birds. The major nesting sites were Sundarijal (534), Keshar Mahal(296), Hanumanghat (220), Indrayani Mandir (181) and Belukhel (53). Cattle Egret can even nest in colony in an urban area. The breeding success rate was 85.29%which showed that Cattle Egret has adopted itself with changing environment. The height of nest varies from 4.17metersJuniperus in dicato 10 meters Ficus benghalensis. The height of roost varies with height of trees. By number Grevilliarobusta was mostly the tree species preferred for nesting while Lisea monoptela,Wendlandia puberula and Ficus religiosa is the least preferred species. By number ofnests,Ficus benghalensis was the most trees species while Palmyra spp was the least preferred species among the trees species utilized for nest building. The day roosting depends upon the availability of food in their feeding grounds and the tree available near by.Populus spp zwas the most preferred tree species for roosting purpose. The distribution of cattle egret shows that northern part of the valley was used for nesting purpose while southern part was used for roosting during cold season(after breeding season). The existing nesting and roosting tree should be preserved and further new tree should be planted. Regular monitoring of cattle egret should be done to know their status in the urban areas.