Channel-billed cuckoos are the heavyweights of nest parasites
Cuckoos and roadrunners fill family Cuculidae, the only Cuculiformes. The clan includes common cuckoos, koels, malkohas, couas, coucals, and anis. The channel-billed cuckoo, about 630 g and 63 cm, is the largest parasitic cuckoo. The family lives on every continent except Antarctica, from tropical rainforest to open desert.
The family Cuculidae spans the little bronze cuckoo, just 17 grams and 15 centimetres, up to birds 60 to 80 centimetres long such as Madagascar's giant coua and the goliath coucal of Halmahera. Most species are slender tree-dwellers, though a sizeable minority live on the ground, and nearly all have long tails used for steering. Migratory species like the black-billed cuckoo have long narrow wings built for strong direct flight.
Old World brood parasites make up the subfamily Cuculinae, whose largest member, the channel-billed cuckoo, carries a bill like a hornbill's. Some parasite chicks mimic their hosts: Asian koels in India hatch black like the crows that raise them, while Australian koel chicks are brown like their honeyeater foster parents. Differences between male and female plumage are rare, turning up mostly among these Old World parasites.
Most cuckoos eat large insects, including hairy caterpillars other birds avoid, and they rub prey against branches before crushing it with bony plates at the back of the mouth. Coucals and roadrunners also club snakes, lizards, rodents and birds with their strong bills, and Caribbean lizard cuckoos specialise in lizards where birds of prey are scarce. Soft feathers get soaked in heavy rain, so cuckoos sun themselves afterwards, and the anis of the Americas, unusually social, breed cooperatively.
The long-tailed koel breeds in New Zealand and winters across Polynesia, Micronesia and Melanesia, a trip hailed as possibly the most impressive sea crossing by any land bird. Within Africa, ten species shuttle between the tropical centre and drier savannahs to breed. Culturally, the cuckoo was sacred to Hera in Greek myth and to Kamadeva, god of desire, in India, while in Europe it heralds spring and gave Shakespeare a joke about cuckoldry in Love's Labour's Lost.
Source: Cuckoo
