The Mekong wagtail (''Motacilla samveasnae'') is a species of

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...

in the family

Motacillidae The wagtails, longclaws, and pipits are a family, Motacillidae, of small passerine birds with medium to long tails. Around 70 species occur in five genera. The longclaws are entirely restricted to the Afrotropics, and the wagtails are predominan ...

. It was first described in 2001 and named in honour of the late Cambodian ornithologist Sam Veasna. It is a black and white bird, similar in appearance to the African pied wagtail, although their ranges do not overlap. Its facial features and distinctive voice distinguish it from other black and white wagtails in southeastern Asia. The Mekong wagtail is found in the

Mekong The Mekong or Mekong River is a trans-boundary river in East Asia and Southeast Asia. It is the world's List of rivers by length, twelfth longest river and List of longest rivers of Asia, the third longest in Asia. Its estimated length is , ...

valley of

Cambodia Cambodia (; also Kampuchea ; km, កម្ពុជា, UNGEGN: ), officially the Kingdom of Cambodia, is a country located in the southern portion of the Indochinese Peninsula in Southeast Asia, spanning an area of , bordered by Thailand t ...

and

Laos Laos (, ''Lāo'' )), officially the Lao People's Democratic Republic ( Lao: ສາທາລະນະລັດ ປະຊາທິປະໄຕ ປະຊາຊົນລາວ, French: République démocratique populaire lao), is a socialist ...

, and is a non-breeding visitor to Thailand and Vietnam. Its typical habitat is rocky areas beside fast-flowing stretches of river where seasonal flooding occurs. Although tolerant of humans, it is threatened by large scale alterations to its habitat such as inundation of riverine habitat following damming of the river.

Description

The Mekong wagtail most closely resembles African pied wagtail ''M. aguimp'', although two species ranges are far apart. It differs from ''M. agiump'' in several minor respects, particularly wing pattern, and its vocalisations are very distinctive. It is a very distinctive species and is the only black-and-white wagtail in South-East Asia which exhibits the plumage character combination of black forehead, lores and ear coverts, obvious white supercilia, with white a throat and neck patch.

Distribution

The

Mekong River The Mekong or Mekong River is a trans-boundary river in East Asia and Southeast Asia. It is the world's twelfth longest river and the third longest in Asia. Its estimated length is , and it drains an area of , discharging of water annuall ...

breeding in

and

, but apparently it is a non breeding visitor to

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...

. It also occurs in

Vietnam Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...

Habitat

The Mekong wagtail is found in wide lowland river channels. Territorial birds are associated with fast-flowing braided sections of river which flow through a distinctive landscape of rocks, bushes adapted to prolonged seasonal submersion, mainly ''

Homonoia riparia ''Homonoia riparia'', the willow-leaved water croton, a mangrove species, belongs to the family Euphorbiaceae. The plant is widely distributed through South Asian and South East Asian countries such as Cambodia, China, Indonesia, Laos, Papua New ...

'', with sandbars and gravel shoals. As river levels rise during the May/June–October/November rainy season these features become flooded. The species concentrates along earthen banks and associated overhanging vegetation, and patches of exposed sand and silt, where they occur in pairs, some of which are highly territorial, and small flocks of less than a dozen birds.

Threats

The Mekong wagtail is very tolerant of human presence, and its habitat is not very susceptible to human-induced changes. Damming proposals along the Mekong, in particular those on sections where the river has a low gradient, have the potential to destroy significant stretches of its riverine range by inundating the river channel

Taxonomy

The species was overlooked until 2001 when it was described. It is named in honour of the late Cambodian ornithologist Sam Veasna. It is most similar in appearance to the African pied wagtail but genetic evidence suggests that the two are not more closely related to each other compared to other black and white wagtails such as the

white wagtail The white wagtail (''Motacilla alba'') is a small passerine bird in the family Motacillidae, which also includes pipits and longclaws. The species breeds in much of Europe and the Asian Palearctic and parts of North Africa. It has a toehold in ...

''M. alba'' complex or the

white-browed wagtail The white-browed wagtail or large pied wagtail (''Motacilla maderaspatensis'') is a medium-sized bird and is the largest member of the wagtail family. They are conspicuously patterned with black above and white below, a prominent white brow, sh ...

''M. maderaspatensis''.

References

External links

Image at ADW

Mekong wagtail The Mekong wagtail (''Motacilla samveasnae'') is a species of bird in the family Motacillidae. It was first described in 2001 and named in honour of the late Cambodian ornithologist Sam Veasna. It is a black and white bird, similar in appearance ...

Birds of Cambodia Birds of Laos

Taxonomy articles created by Polbot {{Passeroidea-stub