EN
White-throated Wren-babbler Rimator pasquieri



Justification

Justification of Red List Category
This species is listed as Endangered owing to knowledge indicative of a decline in the extent and quality of suitable habitat within its very small range, in which it is restricted to only three locations. Further research into the species's status and microhabitat requirements is urgently required.

Population justification
The global population size has not been quantified, but the species is described as scarce within its tiny range.

Trend justification
This species's population is suspected to be undergoing an unquantified decline owing to on-going habitat loss and degradation driven largely by the cultivation of cardamom.

Distribution and population

Rimator pasquieri has a very limited range, being restricted to the Hoang Lien Mountains in West Tonkin, northern Vietnam (del Hoyo et al. 2007). Nine specimens have been collected, all from Mount Fansipan (located in Hoang Lien Son Nature Reserve) (Eames and Mahood 2011). It has also been recorded in recent years at Mu Cang Chai Species and Habitat Conservation Area (Yen Bai Province) and Van Ban Nature Reserve (Lao Cai Province) (Eames and Mahood 2011); although note recorded at the latter in a survey in 2012 (Hung et al. 2015).

Ecology

It inhabits submontane and montane forest habitats, including broadleaf evergreen forest, secondary growth and bamboo stands, at c.1,220-2,500 m (del Hoyo et al. 2007). It appears to strongly favour areas of forest with an undergrowth dominated by dwarf bamboo of the genus Arundinaria (Eames and Mahood 2011). Nothing is known of the species' diet, but it has been observed to skulk on the forest floor and in undergrowth, where it rummages amongst fallen leaves (del Hoyo et al. 2007, Eames and Mahood 2011).

Threats

The species is threatened by on-going forest clearance (Eames and Mahood 2011), although it occurs in secondary growth (del Hoyo et al. 2007) and may tolerate some forms of habitat degradation and disturbance. Cardamom cultivation has increased markedly in north-western Vietnam since c.2006 (J. Pilgrim in litt. 2011) and is perhaps the most important threat to the species (Eames and Mahood 2011). Cardamom cultivation involves the removal of natural undergrowth (dense Arundinaria sp. bamboo) from intact forest and is equally prevalent within and outside protected areas, with the apparent support or tacit acceptance of authorities (Eames and Mahood 2011, J. Pilgrim in litt. 2011). The resulting understorey of cardamom is much simpler in structure than bamboo and is thought to be unsuitable for the species. All recent records have been from locations with a dense understory of Arundinaria sp. bamboo and surveys have thus far failed to find it in cardamom plots. Cardamom cultivation is so widespread that it is reportedly now almost impossible to find undisturbed evergreen forest undergrowth in Hoang Lien Son and Van Ban Nature Reserves (Eames and Mahood 2011, J. Pilgrim in litt. 2011). Cardamom cultivation has recently spread to Mu Cang Chai Species and Habitat Conservation Area, where it was previously uneconomic owing to access constraints. The construction of two new roads that will allow access to this site from the north and the south is on-going and in addition to encouraging cardamom cultivation, these roads will facilitate illegal logging and forest loss. These roads will service four proposed hydroelectric power schemes (at least one of which has been approved for construction) which will inundate land adjacent to the site; the associated work crews and the staff that serve them are likely to be resident in the area for many years, leading to additional forest loss (Eames and Mahood 2011). Fansipan is currently being heavily degraded by tourism, both on site with the development of a cable car, and nearby with recreational facilities and hotels (J. Pilgrim in litt. 2016). Large areas of unprotected montane forest adjacent to this site in Son La Province have been destroyed since c.2001.

Conservation actions

Conservation Actions Underway
It occurs in Hoang Lien Son Nature Reserve, Mu Cang Chai Species and Habitat Conservation Area and Van Ban Nature Reserve, which evidently provide very limited protection (Eames and Mahood 2011, J. Pilgrim in litt. 2011). No targeted actions are known.

Conservation Actions Proposed
Carry out surveys to determine the current status at Van Ban Nature Reserve. Survey new areas of suitable habitat to acquire improved knowledge of its distribution. Carry out surveys to confirm habitat requirements and determine if it can tolerate dense secondary regrowth. Monitor rates of habitat loss and degradation within its range. Improve the management of existing protected areas. Increase the area of suitable habitat that receives robust protection.

Identification

11-12 cm. Small, almost tailless, streaky brown babbler, with a very long, slightly decurved bill and prominent white throat. Its crown, nape and head side are darkish rufescent brown with vague buff streaks. Dorsal feathering long, darkish brown and with long buff streaks, becoming vague on dark rufescent rump. Upperwing and tail plain darkish rufescent-brown, face slightly paler, with dark brown submoustachial streak bordering pure white on chin and throat, with clear-cut break to darkish ochre-tinged brown underparts marked with long whitish-buff streaks.

Acknowledgements

Text account compilers
Taylor, J., Westrip, J., Symes, A., Allinson, T

Contributors
Hung, L., Pilgrim, J., Mahood, S.


Recommended citation
BirdLife International (2017) Species factsheet: Rimator pasquieri. Downloaded from http://www.birdlife.org on 23/11/2017. Recommended citation for factsheets for more than one species: BirdLife International (2017) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 23/11/2017.