The Arctic warbler (''Phylloscopus borealis'') is a widespread

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 20 ...

birch A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech-oak family Fagaceae. The genus ''Betula'' contains 30 ...

or mixed birch

forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...

near water throughout its breeding range in

Fennoscandia __NOTOC__ Fennoscandia (Finnish language, Finnish, Swedish language, Swedish and no, Fennoskandia, nocat=1; russian: Фенноскандия, Fennoskandiya) or the Fennoscandian Peninsula is the geographical peninsula in Europe, which includes ...

and the northern

Palearctic The Palearctic or Palaearctic is the largest of the eight biogeographic realms of the Earth. It stretches across all of Eurasia north of the foothills of the Himalayas, and North Africa. The realm consists of several bioregions: the Euro-Sibe ...

. It has established a foothold in

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

, breeding in

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...

. This warbler is strongly migratory; the entire population winters in

southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consistin ...

. It therefore has one of the longest migrations of any

Old World The "Old World" is a term for Afro-Eurasia that originated in Europe , after Europeans became aware of the existence of the Americas. It is used to contrast the continents of Africa, Europe, and Asia, which were previously thought of by the ...

insectivorous bird. It traditionally included populations that breed in Kamchatka, the

Kuril Islands The Kuril Islands or Kurile Islands (; rus, Кури́льские острова́, r=Kuril'skiye ostrova, p=kʊˈrʲilʲskʲɪjə ɐstrɐˈva; Japanese: or ) are a volcanic archipelago currently administered as part of Sakhalin Oblast in the ...

and

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

, but genetic and vocal evidence strongly suggested these should be treated as separate species, and are all now considered distinct with the

Kamchatka leaf warbler The Kamchatka leaf warbler (''Phylloscopus examinandus'') is a species of leaf warbler (family Phylloscopidae). It was formerly included in the "Old World warbler" assemblage. It is closely related to the Arctic warbler and the Japanese leaf warb ...

in Kamchatka,

Hokkaido is Japan's second largest island and comprises the largest and northernmost prefecture, making up its own region. The Tsugaru Strait separates Hokkaidō from Honshu; the two islands are connected by the undersea railway Seikan Tunnel. The la ...

and the Kuril Islands, and the

Japanese leaf warbler The Japanese leaf warbler (''Phylloscopus xanthodryas'') is a leaf warbler (family Phylloscopidae). The species was first described by Robert Swinhoe in 1863. It was formerly included in the "Old World warbler" assemblage. It is closely related ...

in Japan (except

).Alström, P., Ssaitoh, T., Williams, D., Nishiumi, I., Shigeta, Y., Ueda, K., Irestedt, M., Björklund, M., and Olson, U. (2011). ''The Arctic Warbler Phylloscopus borealis– three anciently separated cryptic species revealed.''

Ibis The ibises () (collective plural ibis; classical plurals ibides and ibes) are a group of long-legged wading birds in the family Threskiornithidae, that inhabit wetlands, forests and plains. "Ibis" derives from the Latin and Ancient Greek word f ...

153(2): 395–410 The nest is on the ground in a low

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

. Like most Old World warblers, this 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 are distinguished from other orders of birds by t ...

is insectivorous. This is a typical leaf warbler in appearance, greyish-green above and off-white below. Its single wing bar distinguishes it from most similar

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

except the

greenish warbler The greenish warbler (''Phylloscopus trochiloides'') is a widespread leaf warbler with a breeding range in northeastern Europe, and temperate to subtropical continental Asia. This warbler is strongly migratory and winters in India. It is not un ...

, ''Phylloscopus trochiloides''. It is larger than that species and has a heavier, dagger-like bill, with a dark tip to the lower mandible. Its

song A song is a musical composition intended to be performed by the human voice. This is often done at distinct and fixed pitches (melodies) using patterns of sound and silence. Songs contain various forms, such as those including the repetitio ...

is a fast trill. This species occurs as an autumn vagrant in western

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

and is annual on

Great Britain Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...

. There were 225 confirmed arctic warbler sightings in Britain between 1958 and 2001. The genus name ''Phylloscopus'' is from

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

''phullon'', "leaf", and ''skopos'', "seeker" (from ''skopeo'', "to watch"). The specific ''borealis'' is from

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

and means "northern".

References

{{Taxonbar, from=Q720497

Arctic warbler The Arctic warbler (''Phylloscopus borealis'') is a widespread leaf warbler in birch or mixed birch forest near water throughout its breeding range in Fennoscandia and the northern Palearctic. It has established a foothold in North America, b ...

Birds of the Arctic Birds of North Asia Birds of Scandinavia

Holarctic birds