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The corn crake, corncrake or landrail (''Crex crex'') is a bird in the rail family. It breeds in Europe and Asia as far east as western China, and migrates to Africa for the northern hemisphere's winter. It is a medium-sized crake with buff- or grey-streaked brownish-black upperparts, chestnut markings on the wings, and blue-grey underparts with rust-coloured and white bars on the flanks and undertail. The strong bill is flesh-toned, the iris is pale brown, and the legs and feet are pale grey. Juveniles are similar in plumage to adults, and downy chicks are black, as with all rails. There are no subspecies, although individuals from the east of the breeding range tend to be slightly paler than their western counterparts. The male's call is a loud ''krek krek'', from which the scientific name is derived. The corn crake is larger than its closest relative, the African crake, which shares its wintering range; that species is also darker-plumaged, and has a plainer face. The corn crake's breeding habitat is grassland, particularly hayfields, and it uses similar environments on the wintering grounds. This secretive species builds a nest of grass leaves in a hollow in the ground and lays 6–14 cream-coloured eggs which are covered with rufous blotches. These hatch in 19–20 days, and the black precocial chicks fledge after about five weeks. This crake is in steep decline across much of its former breeding range because modern farming practices often destroy nests before breeding is completed. The corn crake is omnivorous but mainly feeds on invertebrates, the occasional small frog or mammal, and plant material including grass seed and cereal grain. Natural threats include introduced and feral mammals, large birds, various parasites and diseases. Although numbers have declined steeply in western Europe, this bird is classed as least concern on the IUCN Red List because of its huge range and large, apparently stable, populations in Russia and Kazakhstan.〔 Numbers in western China are more significant than previously thought, and conservation measures have facilitated an increased population in some countries which had suffered the greatest losses. Despite its elusive nature, the loud call has ensured the corn crake has been noted in literature, and garnered a range of local and dialect names. ==Taxonomy== The rails are a bird family comprising nearly 150 species. Although origins of the group are lost in antiquity, the largest number of species and least specialised forms are found in the Old World, suggesting this family originated there. The taxonomy of the small crakes is complicated, but the closest relative of the corn crake is the African crake, ''C. egregia'', which has sometimes been given its own genus, ''Crecopsis'', but is now more usually placed in ''Crex''.〔〔 Both species are short-billed brown birds with a preference for grassland rather than wetland habitats typical of rails. ''Porzana'' crakes, particularly the ash-throated crake (''Porzana albicollis'') are near relatives of the ''Crex'' genus.〔 Corn crakes were first described by Linnaeus in his ''Systema Naturae'' in 1758 as ''Rallus crex'',〔 but was subsequently moved to the genus ''Crex'', created by German naturalist and ornithologist Johann Matthäus Bechstein in 1803, and named ''Crex pratensis''.〔 The earlier use of ''crex'' gives it priority over Bechstein's specific name ''pratensis'', and leads to the current name of ''Crex crex''.〔 The binomial name, ''Crex crex'', from the Ancient Greek "κρεξ", is onomatopoeic, referring to the crake's repetitive grating call.〔〔 The common name was formerly spelt as a single word, "corncrake", but the official version is now "corn crake". The English names refer to the species habit of nesting in dry hay or cereal fields, rather than marshes used by most members of this family.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「corn crake」の詳細全文を読む スポンサード リンク
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