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Classification and description

Thursday 14 March 2013

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<media88|insert|left|credits>The Corncrake (Crex crex) is a member of the Rallidae. This family, which occurs on all continents, contains 133 species. These are mainly aquatic and tend to nest in wetlands.

Classe : Oiseaux
Class : Birds
Order : Gruiformes
Family : Rallidae

Other species of Rallidae that breed in France include the Water Rail (Rallus aquaticus), the Crakes (genus Porzana), the Common Moorhen (Gallinula chloropus), the Purple Swamp-hen (Porphyrio porphyrio) and the Eurasian Coot (Fulica atra).


The Corncrake’s general colour is buff, streaked with black. The extended head, with a laterally compressed strongish bill, is marked by an eyebrow which is blue-grey in the male and rust-coloured in the female.

The relatively short wings are rust-coloured. The sides of the chest, flanks and undertail coverts are a barred rust colour.

The robust legs have well developed pinkish-grey tarsi with long, slender digits

Total body length is 27 to 30 cm. Males weigh between 135 and 200 g, females between 120 and 150 g.

Identifying juveniles

The chicks are born black. They attain their juvenile plumage at the age of 20-25 days. The identification of immature birds is difficult. In autumn, their feathers are more yellowish than those of adults, showing less contrast. The best criterion for judging age is eye colour: the iris is green in juveniles, but varies from yellow to bright orange in older birds.


Credits : chants-oiseaux.fr

During the breeding season, males emit a repetitive, highly audible, far-carrying, disyllabic grating “krek krek”, similar to rubbing a piece of wood against a comb; this is the distinctive cry from which the bird’s scientific and common names are derived.

Both sexes emit sounds like the weak clucking of chickens. Chicks give repeated short chirps.