Pallas's Warbler
Encyclopedia
The Pallas's Warbler or Pallas's Leaf Warbler (Phylloscopus proregulus) is a leaf warbler
which breeds in southern Siberia
(from Novosibirsk Oblast
east to Magadan Oblast
), northern Mongolia
, and northeastern China
. It is strongly migratory
and winters mainly in subtropical southern China
and northeastern Indochina
, but also in small numbers in western Europe
.
It is one of the smallest warblers; at 9–10 cm long and 4–7 g weight it is slightly smaller than a Yellow-browed Warbler
and barely any larger than a Goldcrest
. Overall, it has greenish upperparts and white underparts, but is very striking, with prominent pale yellow wingbars on the tips of the greater and median coverts, bold yellow supercilia and central crown stripe, and a lemon-yellow rump. It is not shy, but its unobtrusive arboreal lifestyle makes it difficult to observe. It is constantly in motion, and often hovers briefly like a Goldcrest. Its song is a medley of whistles, with some phrases reminiscent of a Canary ; the call is a short 'chweey'.
It breeds in coniferous taiga
and mountain forests, and like most warblers, is insectivorous
. The nest is built in a tree, usually next to the trunk at 0.5–10 m above ground; four to six eggs are laid, hatching after 12–13 days, with the chicks fledging when 12–14 days old.
In winter, it uses a slightly broader range of habitats, including broadleaf forest and scrub as well as conifers. Although the vast majority winter in southern China south of the Yangtze River
(where they are present from October to April), small numbers also regularly winter in western Europe
. These arrive in Great Britain
in October to November after a 5,000 km migration from the western end of the breeding range, about the same distance that they would need to fly to reach the normal wintering areas in southern China. Exact numbers in this population are unknown, but up to 300 per year have been found arriving in Great Britain in autumn; given their unobtrusive behaviour, this is probably only a fraction of the total. In the past widely considered to be vagrants
, these birds are now thought to be undertaking a normal regular migration, taking advantage of the mild oceanic climate
winters on the western fringes of Europe for wintering.
, who discovered it on the Ingoda River
in Siberia in 1811; the species name proregulus derives from its similar size to the Goldcrest Regulus regulus. In the past, it was treated as a complex of several subspecies
; apart from the nominate subspecies breeding in northern Asia, two to four other subspecies were accepted, breeding much further south at high altitudes in the Sino-Himalayan mountain system from the western Himalaya east to western China
(Yunnan
north to Gansu
and Hebei
). Even though they differ only slightly in plumage, they are very distinct vocally with both song and calls differing. Genetic analysis has also shown them to be distinct, and they are now treated as separate species:
Of these, Phylloscopus chloronotus forresti is possibly also a separate species, but further analysis is required to confirm this. Gansu Leaf Warbler and Chinese Leaf Warbler overlap in breeding range in southern Gansu, but are separated ecologically, with Gansu Leaf Warbler using taller forest habitats and Chinese Leaf Warbler in lower, often scrubby habitats.
Note that the sixth edition of Clements checklist refers to Pallas's Grasshopper Warbler
, rather than this species, as "Pallas's Warbler".
Leaf warbler
Leaf-warblers are small insectivorous birds belonging mainly to the genus Phylloscopus. They were formerly included in the Old World warbler family but are now considered to belong to the Phylloscopidae, a family created in 2006. The genus is closely related to Seicercus and some species have been...
which breeds in southern Siberia
Siberia
Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
(from Novosibirsk Oblast
Novosibirsk Oblast
Novosibirsk Oblast is a federal subject of Russia located in southwestern Siberia. Its administrative and economic center is the city of Novosibirsk. Population: -Overview:...
east to Magadan Oblast
Magadan Oblast
Magadan Oblast is a federal subject of Russia in the Far Eastern Federal District. Its administrative center is the city of Magadan....
), northern Mongolia
Mongolia
Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...
, and northeastern China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
. It is strongly migratory
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
and winters mainly in subtropical southern China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
and northeastern Indochina
Indochina
The Indochinese peninsula, is a region in Southeast Asia. It lies roughly southwest of China, and east of India. The name has its origins in the French, Indochine, as a combination of the names of "China" and "India", and was adopted when French colonizers in Vietnam began expanding their territory...
, but also in small numbers in western Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
.
It is one of the smallest warblers; at 9–10 cm long and 4–7 g weight it is slightly smaller than a Yellow-browed Warbler
Yellow-browed Warbler
The Yellow-browed Warbler is a leaf warbler which breeds in temperate Asia. This warbler is strongly migratory and winters mainly in tropical southeast Asia, but also in small numbers in western Europe...
and barely any larger than a Goldcrest
Goldcrest
The Goldcrest, Regulus regulus, is a very small passerine bird in the kinglet family. Its colourful golden crest feathers gives rise to its English and scientific names, and possibly to it being called the "king of the birds" in European folklore. Several subspecies are recognised across the very...
. Overall, it has greenish upperparts and white underparts, but is very striking, with prominent pale yellow wingbars on the tips of the greater and median coverts, bold yellow supercilia and central crown stripe, and a lemon-yellow rump. It is not shy, but its unobtrusive arboreal lifestyle makes it difficult to observe. It is constantly in motion, and often hovers briefly like a Goldcrest. Its song is a medley of whistles, with some phrases reminiscent of a Canary ; the call is a short 'chweey'.
It breeds in coniferous taiga
Taiga
Taiga , also known as the boreal forest, is a biome characterized by coniferous forests.Taiga is the world's largest terrestrial biome. In North America it covers most of inland Canada and Alaska as well as parts of the extreme northern continental United States and is known as the Northwoods...
and mountain forests, and like most warblers, is insectivorous
Insectivore
An insectivore is a type of carnivore with a diet that consists chiefly of insects and similar small creatures. An alternate term is entomophage, which also refers to the human practice of eating insects....
. The nest is built in a tree, usually next to the trunk at 0.5–10 m above ground; four to six eggs are laid, hatching after 12–13 days, with the chicks fledging when 12–14 days old.
In winter, it uses a slightly broader range of habitats, including broadleaf forest and scrub as well as conifers. Although the vast majority winter in southern China south of the Yangtze River
Yangtze River
The Yangtze, Yangzi or Cháng Jiāng is the longest river in Asia, and the third-longest in the world. It flows for from the glaciers on the Tibetan Plateau in Qinghai eastward across southwest, central and eastern China before emptying into the East China Sea at Shanghai. It is also one of the...
(where they are present from October to April), small numbers also regularly winter in western Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
. These arrive in Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
in October to November after a 5,000 km migration from the western end of the breeding range, about the same distance that they would need to fly to reach the normal wintering areas in southern China. Exact numbers in this population are unknown, but up to 300 per year have been found arriving in Great Britain in autumn; given their unobtrusive behaviour, this is probably only a fraction of the total. In the past widely considered to be vagrants
Vagrancy (biology)
Vagrancy is a phenomenon in biology whereby individual animals appear well outside their normal range; individual animals which exhibit vagrancy are known as vagrants. The term accidental is sometimes also used...
, these birds are now thought to be undertaking a normal regular migration, taking advantage of the mild oceanic climate
Oceanic climate
An oceanic climate, also called marine west coast climate, maritime climate, Cascadian climate and British climate for Köppen climate classification Cfb and subtropical highland for Köppen Cfb or Cwb, is a type of climate typically found along the west coasts at the middle latitudes of some of the...
winters on the western fringes of Europe for wintering.
Taxonomy
Pallas's Warbler is named after the German zoologist Peter Simon PallasPeter Simon Pallas
Peter Simon Pallas was a German zoologist and botanist who worked in Russia.- Life and work :Pallas was born in Berlin, the son of Professor of Surgery Simon Pallas. He studied with private tutors and took an interest in natural history, later attending the University of Halle and the University...
, who discovered it on the Ingoda River
Ingoda River
Ingoda River is a river in Zabaykalsky Krai of Russia. The length of the river is 439 miles . The area of its basin is 37,200 km². Together with the Onon River, it forms the Shilka River. Unlike the nearby Yazanrifai river, the Ingoda River freezes up in early November and stays under the ice...
in Siberia in 1811; the species name proregulus derives from its similar size to the Goldcrest Regulus regulus. In the past, it was treated as a complex of several subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
; apart from the nominate subspecies breeding in northern Asia, two to four other subspecies were accepted, breeding much further south at high altitudes in the Sino-Himalayan mountain system from the western Himalaya east to western China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
(Yunnan
Yunnan
Yunnan is a province of the People's Republic of China, located in the far southwest of the country spanning approximately and with a population of 45.7 million . The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.Yunnan is situated in a mountainous area, with...
north to Gansu
Gansu
' is a province located in the northwest of the People's Republic of China.It lies between the Tibetan and Huangtu plateaus, and borders Mongolia, Inner Mongolia, and Ningxia to the north, Xinjiang and Qinghai to the west, Sichuan to the south, and Shaanxi to the east...
and Hebei
Hebei
' is a province of the People's Republic of China in the North China region. Its one-character abbreviation is "" , named after Ji Province, a Han Dynasty province that included what is now southern Hebei...
). Even though they differ only slightly in plumage, they are very distinct vocally with both song and calls differing. Genetic analysis has also shown them to be distinct, and they are now treated as separate species:
- Lemon-rumped Warbler Phylloscopus chloronotus. Himalaya, SW China. Three subspecies, P. c. chloronotus, P. c. forresti, P. c. simlaensis.
- Gansu Leaf Warbler Phylloscopus kansuensis. Central western China. Monotypic.
- Chinese Leaf Warbler Phylloscopus yunnanensis (syn. P. sichuanensis). Western China. Monotypic.
Of these, Phylloscopus chloronotus forresti is possibly also a separate species, but further analysis is required to confirm this. Gansu Leaf Warbler and Chinese Leaf Warbler overlap in breeding range in southern Gansu, but are separated ecologically, with Gansu Leaf Warbler using taller forest habitats and Chinese Leaf Warbler in lower, often scrubby habitats.
Note that the sixth edition of Clements checklist refers to Pallas's Grasshopper Warbler
Pallas's Grasshopper Warbler
The Pallas's Grasshopper Warbler, Locustella certhiola, is an Old World warbler in the grass warbler genus Locustella. It breeds in east Asia. It is migratory, wintering from India east to Indonesia....
, rather than this species, as "Pallas's Warbler".