Common Grasshopper Warbler

Identification

The adult common grasshopper warbler (the name is the IOC recommended English name) has a length of about 12.5 cm (5 in). It is a very secretive bird and seldom seen, but its presence is easily detected because of its characteristic song. The upper-parts are pale olive-brown, each feather having a central darker brown streak. The cheeks are greyish, the irises are brown and there is a faint eye streak behind the eye. The upper mandible of the beak is dark brown and the lower mandible yellowish-brown. The underparts are cream-coloured or yellowish-buff with a few dark brown spots and streaks on the breast and flanks. The wings are brown with the outer edge of the feathers rimmed with paler brown. The tail feathers are reddish-brown with faint transverse bars being visible in some individuals and the under-tail coverts are streaked. The slender legs and the feet are pale yellowish-brown.<p>The song is an unmusical long, high-pitched reeling trill performed with beak held wide open and the whole body vibrating. It lasts for from a few seconds to two or three minutes with hardly a pause for breath. It varies in volume from a faint hum to a sound resembling a distant mowing machine. It is performed at any time of day from early morning until after the sun has set and is constantly to be heard from the arrival of the bird in spring until late July. The alarm call is a repeated ticking noise that has been rendered as "twkit-twkit-twkit". The song is similar to that of its congeners: the lanceolated warbler (Locustella lanceolata), Savi's warbler (Locustella luscinioides) and the river warbler (Locustella fluviatilis).

Taxonomy

The Italian naturalist Ulisse Aldrovandi included the common grasshopper warbler in the second volume of his Ornithologiae. Aldrovandi died in 1605 but the volume was not published until 1637. In 1760 the French zoologist Mathurin Jacques Brisson included a detailed description of the common grasshopper warbler in his Ornithologie. He used the French name La fauvette tachetée and the Latin name Curruca naevia but although Brisson coined Latin names, these do not conform to the binomial system and are not recognised by the International Commission on Zoological Nomenclature.<p>The common grasshopper warbler was described by the French polymath Georges-Louis Leclerc, Comte de Buffon in 1779 in his Histoire Naturelle des Oiseaux. The bird was also illustrated in a hand-coloured plate engraved by François-Nicolas Martinet in the Planches Enluminées D'Histoire Naturelle which was produced under the supervision of Edme-Louis Daubenton to accompany Buffon's text. Neither the plate caption nor Buffon's description included a scientific name but in 1783 the Dutch naturalist Pieter Boddaert coined the binomial name Motacilla naevia in his catalogue of the Planches Enluminées; he used the word naevia that had earlier been used by Brisson. The type locality is Bologna in Italy. The common grasshopper warbler is now one of 20 species placed in the genus Locustella that was introduced by the German naturalist Johann Jakob Kaup in 1829 with the common grasshopper warbler as the type species. The genus name Locustella is from Latin and is a diminutive of locusta, "grasshopper". The specific naevia is Latin for "spotted ".<p>Four subspecies are recognised.

Scientific name

Locustella naevia

Authority

(Boddaert, 1783)

Order

Passeriformes

Family

Locustellidae

Genus

Locustella

Range and habitat

The common grasshopper warbler breeds in northwest Europe and the western Palearctic. The range includes Spain, France, central Italy, Romania, Yugoslavia, the British Isles, Belgium, Netherlands, Germany, Denmark, southern Sweden, southern Finland, the Baltic States and western parts of Russia. Further east it is replaced by related species. In late summer, it migrates to northwest Africa, India and Sri Lanka where it overwinters.<p>In the breeding season, the common grasshopper warbler is found in damp or dry places with rough grass and bushes such as the edges of fens, clearings, neglected hedgerows, heaths, upland moors, gorse-covered areas, young plantations and felled woodland. In the winter, it is usually found in similar locations but information is scarce on its behaviour and habitat at this time.

Breeding range

PAL : widespread

Non-breeding range

s Asia and n AF

Migration

Complete migrants

Behavior

Migration pattern: Complete migrants.

Conservation

Population trend: stable.

Population trend

stable