Cuculus canorus - Common Cuckoo
Feather characters. Barbules are extremely long (2.8-4.2 mm) and pigment is concentrated in parts of internodes (no pigment in nodes). Diamond-shaped nodes are equally distributed along the entire length of barbules (12-16 per mm). They are all about the same size, slightly decreasing towards distal end. Villi are absent and internodes are occasionally kinked. Minute prongs may be present on distal end of barbules and on both sides of the pennulum.
Field characters. Size 33 cm. Weight 113 g (Dunning, 1993). Best-known for brood-parasitism and male's song. Slate-grey head and upperparts, ash-grey throat and chest, white underparts with blackish bars (except on vent), dark grey wing and grey-black tail with white spots on tip and along margins. In female, a rare rufous morph has upperparts chestnut, barred black; head and chest somewhat lighter and more finely barred; underparts white with brownish wash, finely barred black; wing and tail dark brown with broad chestnut bars; tail-feathers white tipped. In juveniles of either sex both morphs are common; grey morph lacks bluish tinge of male adult, being more dark grey; upperparts finely barred with black. Rufous morph is duller in colour and more prominently barred than rufous female; colour pattern of either morph similar to that of adults, but distinguishable by white spot on nape, white feather margins on entire plumage, and considerable white spotting on tail. Potential hosts include wagtails, pipits, wrens (Troglodytidae, not included in BRIS) and warblers.
Voice. Song of male "cu-coo"; female has liquid musical note not unlike the sound of bubbling water and resembling that of Little Grebe.
Distribution. A common bird in Europe; winters in Africa. Map: see MapIt.
Habitat. Very varied; no special preference known, although it shuns very cold and hot habitats (arctic tundra and desert); presence of brood-hosts and high look-outs are a prerequisite.
Food. Predominantly caterpillars, even hairy ones avoided by other birds; beetles and other insects. When laying egg in host's nest, an egg is taken and eaten.