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Foraging behaviour of the Near Threatened Grey-Headed Bulbul Pycnonotus priocephalus in Relation to Seasons and Breeding Stages
I studied the foraging behaviour and adaptive strategies of the Grey-headed Bulbul Pycnonotus priocephalus, an endemic species of the Western Ghats, India, in relation to seasons and reproductive stages in two tropical rainforest sites, Silent Valley National Park and Muthikkulam Reserve Forest, from 2002 to 2005 and 2012 to 2013. The species was recorded to use various foraging manoeuvres and food handling techniques, and was found to frequently use energy conserving manoeuvres and feeding techniques such as gleaning and gulping. There were significant differences in its foraging height and foraging tree use due to differential habitat selection during the breeding and non-breeding seasons. It showed plasticity in the foraging behaviour during the different reproductive stages. Its participation in mixed-hunting flocks during the local migratory phase (non-breeding season) seems to be an adaptive strategy to cope with resource competition and predation risks in a new and challenging habitat, which is in accordance with other studies on the flocking behaviour of tropical birds.
Behavioural Plasticity, Foraging Behaviour, Grey-Headed Bulbul, Mixed-Species Flocks, Pycnonotus Priocephalus, Western Ghats.
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