In the past few weeks, I have been noticing more regularly in our campus “mixed hunting flocks” or “bird waves”, where birds of different species gather in one location and move in a loose flock, looking out for food. This is a regular occurrence (especially in the non-breeding season) in many forest areas and has been well-studied. In moving around in flocks, all birds benefit from each others’ company – when one bird moves, it disturbs some insect which another bird is able to catch and devour or the presence of a flocks lends security to the group members and so they get an early warning signal when a hawk makes an appearance.
In Rishi Valley, the Ashy Drongo, a winter visitor from the Himalaya, appears to lead the hunting flock and also warns the group of potential predators. A typical flock consists of the ground feeding yellow-billed babblers (and in some cases, Tawny-bellied babblers), which while moving about disturb the insects from the leaf litter, Cinereous (grey) Tits, Paradise Flycatchers, bulbul species, Magpie-robins, Tailorbirds, Hoopoes (in more open habitats), warblers, etc.
Last week I observed flocks of the Oriental White-eyes in several parts of the campus. I had seen a few of these birds, which are rather common in the nearby Horsley Hills (at higher elevations), once or twice in the last couple of years in the campus. This species features in our “Birds of Rishi Valley” book but I had never seen them on campus until last couple of years. I suspect they were included in the book on the basis of their presence at Horsley Hills. So is this another species that is now colonising our campus? We do not know if they are here only for the winter months or will stay back and breed in the campus.