The common cuckoo (Cuculus canorus) is a summer breeder in Mongolia.
Adult male has grey plumage. Upperparts are ashy-grey, including the wings. The tail is dark brownish with white spots and tips, and black bars.Underparts are white, heavily barred dark grey to black. Chin and upper breast are pale ashy-grey. Undertail feathers are black with white spots and edges. Head is grey. The bill is yellow at base and black-tipped. Eyes are yellowish-brown to orange, surrounded by yellow eye-ring. Legs and feet are orange-yellow.
Female is almost similar, except the upper breast which is rather rufous than grey. In the race “canurus” we can find a rufous morph in females, with chestnut tinge instead grey.
Juvenile has pale brown upperparts, heavily barred black, with white-tipped feathers. Tail is strongly barred black.
Underparts are white, finely barred dark grey. Eyes are dark brown with yellow eye-ring.
Length : 32-36 cm
Wingspan: 54-60 cm
Weight : 115 gr
Habitat: Common Cuckoo frequents coniferous and deciduous forests and woodlands, open wooded areas, forest edges and clearings, steppes with trees, meadows, marshes and reedbeds, cultivated areas with trees and bushes. It may be found up to 2000 metres of elevation, and much more according to the range.
Diet: Common Cuckoo feeds primarily on insects and caterpillars. These hairy caterpillars are rejected by the other birds’ species. But in order to avoid to be poisoned, the cuckoo bites one end of the insect and slices it open with the bill, and then, it shakes it to extract the toxic matter before to swallow it. The hairs of the caterpillar are regurgitated later in pellets.
Behavior: Common Cuckoo is a shy bird, often seen alone outside breeding season. At this time, they become noisier, both male and female uttering their calls.
Common Cuckoo perches in exposed tree or pole, with cooked and spread tail, and drooped wings.
Common Cuckoo is a brood parasite, which means female lays her eggs in other birds’ nests. Some explanations about this particular behaviour try to give the reasons. Common Cuckoos adults feed on poisonous insects. This food is not adapted to chicks and young birds. So, parents choose other host species, able to provide good food to their young.
They commonly be found in the northern, north-eastern, north-western parts of Mongolia in open woodland, edges of mountain taiga and riparian forests.
Read about the 10 Strange Facts About Cuckoo on our Bird Mongolia Blog.