The time budget and behavioural traits of young and adult Indian Eagle Owl Bubo bengalensis (Franklin, 1831) (Aves: Strigiformes: Strigidae) in and around a nesting site: a preliminary report

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M. Eric Ramanujam


A family of the Indian Eagle Owl Bubo bengalensis was monitored at their nest site at Nanmangalam Reserve Forest on the outskirts of Chennai City from 5 January to 8 March 2011.  Various behavioural patterns were identified and the time spent on each activity was noted.  All three types of subjects (viz.: breeding male, brooding/incubating female and young) showed different behavioural characteristics. In the breeding female, high intensity activities were incubation, brooding, vigilance and out of sight (construed to be out hunting) and low intensity activities comprised comfort movements, feeding, pellet regurgitation, feeding young, prey delivery and disturbed at the nest.  In the young, high intensity activities were resting and moving, while low intensity activities were feeding, pellet regurgitation and wing flapping.  In the male, the bulk of time was spent in vigilance and the other high intensity activity was out of sight (construed to be hunting).  Low intensity activities included comfort movements and prey delivery. The male hunted more than the female.  Forty-five prey items were delivered by the two parents and these items were identified to the species or generic level.


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