The western Bonelli's warbler (''Phylloscopus bonelli'') is a

warbler Various Passeriformes (perching birds) are commonly referred to as warblers. They are not necessarily closely related to one another, but share some characteristics, such as being fairly small, vocal, and insectivorous. Sylvioid warblers T ...

in the

leaf warbler Leaf warblers are small insectivorous passerine birds belonging to the genus ''Phylloscopus''. Leaf warblers were formerly included in the Old World warbler family but are now considered to belong to the family Phylloscopidae, introduced in 2006 ...

genus '' Phylloscopus''. It was formerly regarded as the western subspecies of a wider "Bonelli's warbler" species, but as a result of modern taxonomic developments, they are now usually considered to be two species: * Western Bonelli's warbler, ''Phylloscopus bonelli'', which breeds in southwest

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

and north

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

* Eastern Bonelli's warbler, ''Phylloscopus orientalis'', which breeds in southeast

and

Asia Minor Anatolia (), also known as Asia Minor, is a peninsula in West Asia that makes up the majority of the land area of Turkey. It is the westernmost protrusion of Asia and is geographically bounded by the Mediterranean Sea to the south, the Aegean ...

The breeding ranges of the two species do not overlap; while their appearance and songs are very similar, the calls are completely different (see below). They also show marked difference in

mtDNA Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in ...

sequence In mathematics, a sequence is an enumerated collection of objects in which repetitions are allowed and order matters. Like a set, it contains members (also called ''elements'', or ''terms''). The number of elements (possibly infinite) is cal ...

. The species is migratory, wintering in sub-

Sahara The Sahara (, ) is a desert spanning across North Africa. With an area of , it is the largest hot desert in the world and the list of deserts by area, third-largest desert overall, smaller only than the deserts of Antarctica and the northern Ar ...

. It is a rare vagrant in Northern Europe. The genus name ''Phylloscopus'' is from

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

''phullon'', "leaf", and ''skopos'', "seeker" (from ''skopeo'', "to watch"). The English name and the specific ''bonelli'' are for the Italian ornithologist

Franco Andrea Bonelli Franco Andrea Bonelli (10 November 1784 – 18 November 1830) was an Italian ornithology, ornithologist, entomologist and collector. He worked at the University of Turin and was involved in organizing the collections of the natural history museu ...

Description

Western Bonelli's warbler is a small

passerine A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped') which includes more than half of all bird species. Sometimes known as perching birds, passerines generally have an anisodactyl arrangement of their ...

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

, found in forest and woodland. Four to six eggs are laid in a nest on the ground. The eggs are white with reddish-brown markings and are laid in clutches of 3-5 eggs. The incubation period is around 14 days long, and the chicks fledge after 10-14 days. Cuckoo nest predation and brood parasitism are major hazards to the breeding success of western Bonelli's warblers. Like most warblers, western Bonelli's warbler is insectivorous. The adult has a plain grey-green back, green-toned rump and wings and whitish underparts. The bill is small and pointed and the legs brown. The sexes are identical, as with most warblers. The western Bonelli's warbler has a browner tinge to the upperparts than the eastern Bonelli's warbler; the latter sometimes has a greenish tinge instead. The song is a fast monotone trill, only slightly different from eastern Bonelli's, and also with some similarity to the

wood warbler The wood warbler (''Phylloscopus sibilatrix'') is a common and widespread leaf warbler which breeds throughout northern and temperate Europe, and just into the extreme west of Asian Russia in the southern Ural Mountains. This warbler is stro ...

. The call of the western Bonelli's warbler is a disyllabic ''hu-it'', differing from that of the eastern Bonelli's warbler which is a hard ''chup'', reminiscent of a

crossbill Crossbills are birds of the genus ''Loxia'' within the finch family (Fringillidae), with six species. These birds are characterized by the mandibles with crossed tips, which gives the group its English name. Adult males tend to be red or orange ...

or a

house sparrow The house sparrow (''Passer domesticus'') is a bird of the Old World sparrow, sparrow family Passeridae, found in most parts of the world. It is a small bird that has a typical length of and a mass of . Females and young birds are coloured pa ...

.Helb, H.-W.; Bergmann, H.-H. & Martens, J. (1982): Acoustic differences between populations of western and eastern Bonelli's Warblers (''Phylloscopus bonelli'', Sylviidae). ''Cellular and Molecular Life Sciences'' 38(3): 356–357. Phylloscopus bonelli MHNT

References

External links

Ageing and sexing (PDF; 2.5 MB) by Javier Blasco-Zumeta & Gerd-Michael Heinze
{{Taxonbar, from=Q752489

western Bonelli's warbler The western Bonelli's warbler (''Phylloscopus bonelli'') is a warbler in the leaf warbler genus ''Phylloscopus''. It was formerly regarded as the western subspecies of a wider "Bonelli's warbler" species, but as a result of modern taxonomic devel ...

Birds of Europe Birds of Southern Europe Birds of North Africa Birds of West Africa