These, the world's smallest cuckoo, are found throughout Australia in all but the driest areas, they are also found from the Malay Peninsula through Indonesia and across to southern New Guinea.
They are fairly common in a wide range of habitats such as open woodland, coastal scrub and forest that have a range of under-story plants such as grasses, shrubs or heath.
Their diet is almost entirely insects and their larvae, especially hairy caterpillars, although they may sometimes eat plant matter.
Like many other cuckoos they are nest parasites with most of the recorded hosts being gerygones of one sort or another. The female, who differs from the male in having a pale eye ring, lays one egg in the host's nest, this egg can sometimes resemble the host's eggs in markings but not necessarily. The relationship between parasite and host birds is complex and outside the scope of this article, sometimes the host evicts the imposter and sometimes the newly hatched young cuckoo ejects the eggs or nestlings of the host. When the Cuckoo is successful the host parents incubate the cuckoo egg and feed the young for up to several weeks after it fledges.