Savi's warbler (Locustella luscinioides) is a species of Old World warbler in the genus Locustella. It breeds in Europe and the western Palearctic. It is migratory, wintering in northern and sub-Saharan Africa.
This small passerine bird is found in reed beds, usually with some bushes. Three to six eggs are laid in a nest in reeds. The adult has an unstreaked grey-brown back, whitish grey underparts and a lack of throat streaks, which is a distinction from the river warbler. The sexes are identical, as with most warblers, but young birds are yellower below. Like most warblers, it is insectivorous. This is not a shy species, but can be difficult to see in the reeds except sometimes when singing.
The song is a monotonous mechanical insect-like reeling, often given at dusk. It is similar to the song of other species in the group, but is generally faster and deeper and bears a strong resemblance to that of Roesel's bush-cricket.
Taxonomy
The common name of this bird recognises the Italian ornithologist Paolo Savi, the author of "Ornitologia Toscana" (1827–1831) and "Ornitologia Italiana" (1873–1876). In 1821, Savi was given specimens of an unstreaked, dark, rufous-brown warbler which was new to science. He published a full description of the bird in 1824, and it became known by the common name of Savi's warbler. The genus name Locustella is from Latin and is a diminutive of locusta, "grasshopper". This refers to the song of the common grasshopper warbler and some others in this genus. The specific luscinioides is from Latin luscinia, "nightingale", and Ancient Greek -oides, "resembling".
There are three subspecies. Locustella luscinioides luscinioides is the nominate subspecies which is native to Central and Eastern Europe, Spain, Portugal and North Africa. It winters in West Africa in an area stretching from Senegal to Lake Chad and northern Ghana, and probably also in South Sudan.
Description
thumb|left|Singing from an [[alder tree]]
The upper-parts of Savi's warbler are a uniform dark reddish-brown, sometimes with a slight greenish tinge. It has indistinct buff eye-stripes, dark lores and pale brown ear-coverts. The brown beak is slender and the irises are also brown. The chin, throat and belly are whitish-buff and the rest of the underparts sandy brown. In the breeding season, both upper-parts and underparts are slightly paler. The legs are brown. The bird is around long.
The song is a trill very similar to that of the grasshopper warbler but slightly lower pitched and less prolonged. It is often preceded by a series of low ticks which gradually merge into the trill. The bird sings from high on a reed head with open beak and vibrating throat. Both males and females sing. The nest is built by the female on a little reed platform in the manner of a moorhen's nest and is well concealed among dead reeds and clumps of vegetation. It is often made from leaves of Glyceria but some nests instead are neatly lined with fine grasses and leaves. It is not usually visible from above. Four to six (occasionally three) eggs are laid. They are greyish-white, liberally speckled with greyish rusty-coloured spots, sometimes in a darker band round the egg. They measure about <!--is this level of precision appropriate?-->. Incubation lasts for about twelve days and is done exclusively by the female. She also feeds the chicks when they first hatch with the male joining in as they grow. The young fledge in about twelve days and there are normally two broods.