Predatory behaviour of black drongo (Dicrurus adsimilis) in response to use of different insecticides was conducted during the year 1994-95 at Agricultural Research Station, Gulbarga, a pigeonpea bowl of Kamataka. The results indicated that predatory activity of drongo was hampered in synthetic insecticide sprayed plots due to reduction in the larval population in treated plots than direct effect of toxication as it is an aerial predator. Secondly, aerial predators particularly drongo. were not much affected as they do not prey on the ground population. This differential behaviour of the predatory habit reduced its chance to get fully toxicated larva. While, the ground predators especially flocks of mynah and sparrows failed to discriminate the toxicated larvae exhibiting feigning death fallen on the ground. In HaNPV and NSKE treated plots, the predatory activity was not interrupted. Particularly in HaNPV sprayed plots, predatory efficiency of drongo increased on fourth and fifth day after spraying. Further, bird droppings contained virulent virus particles (7x10⁸ POB/ml) and therefore, birds served as virus disseminating agents in nature.