||Acrocephalus tangorum La Touche, 1912
||White-browed Reed-warbler, Manchurian Reed-warbler, Manchurian Reed Warbler
||del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.
||13 cm. Small, drab reed-warbler. Uniform tawny-rufous upperparts. Bold, whitish supercilium bordered by dark brow and narrow eye-stripe. White chin, throat and belly becoming buffish-brown on flanks. Similar spp. Paddyfield Warbler A. agricola has less tawny-rufous upperparts and less clearly defined black eyebrow. Black-browed Reed-warbler A. bistrigiceps has more extensive dark crown and more obvious contrast between the black brow and pale centre of crown. Generally duller and more olive-brown upperparts. Voice Typical Acrocephalus song. Calls include a sharp chik-chik, a harsh chr-chuck and a slurred zack-zack.
|Red List Category & Criteria:
||Butchart, S. & Symes, A.
||Davidson, P., Hornskov, J., Mulligan, B., Round, P. & Duckworth, W.
||Benstead, P., Bird, J., Peet, N., Taylor, J., Allinson, T, Martin, R, North, A., Westrip, J.
This species qualifies as Vulnerable because it has a small, declining population as a result of habitat loss in both its breeding and wintering grounds.
|Previously published Red List assessments:|
- 2016 – Vulnerable (VU)
- 2012 – Vulnerable (VU)
- 2008 – Vulnerable (VU)
- 2007 – Vulnerable (VU)
- 2004 – Vulnerable (VU)
- 2000 – Vulnerable (VU)
- 1994 – Not Recognized (NR)
- 1988 – Not Recognized (NR)
|Range Description:||Acrocephalus tangorum breeds in south-east Russia and north-east China, and winters in southern Laos, Cambodia, Thailand and Peninsular Malaysia (BirdLife International 2001, Kee and Bakewell 2015). It occurs as a scarce passage migrant in Hebei, Liaoning and Hong Kong in China, Pakxan wetlands in Lao (W. Duckworth in litt. 2012) and in Vietnam. Few breeding sites are known. In China, Alström et al. (1991) reported that the species was locally common at Zhalong National Nature Reserve and is still present at Dalai Hu National Nature Reserve, Inner Mongolia, but little habitat remained at two other known sites. In Russia Khanka Lake is the best known site, though updated data on the size and trend of the population is required. |
Grasslands within the Tonle Sap floodplain in Cambodia are perhaps the most important wintering habitat and it has been noted to be locally common (Bird et al. 2007, Bird et al. 2012), however declines have been noted within the last decade (Goes 2013). Elsewhere the species is decidedly localised and rare, with small numbers regular at Khao Sam Roi Yot, Thailand, and recent observations in Perlis and Pulau Pinang in Malaysia (Kee and Bakewell 2015). The paucity of recent records for well-watched and increasingly heavily monitored and ringed sites (such as Mai Po in Hong Kong and Bung Boraphet in Thailand) suggest it is genuinely very scarce (P. Round in litt. 2012).
Cambodia; China; Lao People's Democratic Republic; Malaysia (Peninsular Malaysia); Myanmar; Russian Federation (Eastern Asian Russia); Thailand; Viet Nam
Hong Kong; Korea, Republic of
|♦ Continuing decline in area of occupancy (AOO):||Unknown|
|♦ Extreme fluctuations in area of occupancy (AOO):||No||♦ Estimated extent of occurrence (EOO) - km2:||303000|
|♦ Continuing decline in extent of occurrence (EOO):||Unknown||♦ Extreme fluctuations in extent of occurrence (EOO):||No|
|♦ Number of Locations:||11-100||♦ Continuing decline in number of locations:||Unknown|
|♦ Extreme fluctuations in the number of locations:||No|
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||The global population estimate of 2,500-9,999 mature individuals is based on a detailed analysis of records by BirdLife International (2001), where it was concluded that the species must have a fairly small world population (i.e. fewer than 10,000). This estimate equates to 3,750-14,999 individuals, rounded here to 3,500-15,000 individuals. All individuals are considered to belong to a single population on the basis of the migratory nature of the species and the lack of clear division within the known breeding range of the species.|
Trend Justification: Although perhaps more common than it was thought to be in the 1990s, this species is suspected to be continuing to decline at a moderate rate, owing to the conversion of many natural systems. While it may be tolerant of some modified habitats, the species is unlikely to cope with heavily intensified agricultural and urban environments.
|Current Population Trend:||Decreasing|
|♦ Number of mature individuals:||2500-9999||♦ Continuing decline of mature individuals:||Yes|
|♦ Extreme fluctuations:||No||♦ Population severely fragmented:||No|
|♦ No. of subpopulations:||1||♦ Continuing decline in subpopulations:||No|
|♦ Extreme fluctuations in subpopulations:||No||♦ All individuals in one subpopulation:||Yes|
|♦ No. of individuals in largest subpopulation:||100|