Intensity of Brood Parasitism of Asian Koel (Eudynamys scolopacea) in the Nest of House Crow (Corvus splendens) and Jungle Crow (Corvus macrorhynchos) in Anand Region of Gujarat, India

The Koel or Asian Koel (Eudynamys scolopacea) does not build its own nest to raise its own family but lay eggs in the nests of the members of Corvidae family, i. e. House Crow (Corvus splendens) and Jungle Crow (Corvus macrorhynchos). The breeding season of this brood parasite (Asian Koel) coincides with that of its host (House Crow and Jungle Crow) during February to August. However, two crow species has distinct breeding season. Per cent brood parasitism and eggs of Asian Koel was observed higher in the nests of Jungle Crow (73.68%) compared to House Crow (33.33%). Though lower parasitism of Koel was recorded in the nests of House Crow, survival of Koel chicks was greater in the nests of House Crow (52.63%) compared to Jungle Crow (35.71%). Length, width and weight of Koel eggs in the nest of Jungle Crow was 29.97 ± 1.16 mm, 22.97 ± 0.84 mm and 8.79 ± 0.83 g, respectively and in House Crow nests it was recorded as 28.08 ± 0.66 mm, 22.05 ± 0.59 mm and 8.18 ±0.35 g., respectively. Host survival per cent in Koel parasitised nests was observed similar in both crow species (House Crow and Jungle Crow) with very low rate (20.83% 20.93% respectively) compared to un-parasitised nests (28.07% and 42.11%, respectively).