LC
White-browed Jungle-flycatcher Vauriella insignis



Justification

Justification of Red List category
This species it is not believed to approach the thresholds for Vulnerable under the range size criterion (extent of occurrence <20,000 kmcombined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend is suspected to be stable, and hence does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is unknown but is unlikely to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Population justification
This species is described as rare and local (Dickinson et al. 1991, Poulsen 1995, Allen 2020), and the global population size has not been quantified. It is generally shy, quiet and difficult to observe (Poulsen 1995, L. Heaney in litt. 2019), but trapping studies have revealed it to be common at Balbalan-Balbalasang National Park, Kalinga Province, on Mt. Amuyao, Mountain Province, and Mt. Sicapoo, Apayao Province (L. Heaney in litt. 2007, 2019). It may have been previously under-recorded owing to its furtive nature and could prove to be more widespread, however trapping studies at various montane sites outside the Cordillera Central and Sierra Madre between 2000 and 2007 failed to find it (L. Heaney in litt. 2007). It has probably never been numerous (Poulsen 1995), though given the area of habitat remaining within the range the global population size is unlikely to be especially small.

Trend justification
This species may be affected locally by deforestation and degradation particularly in the southern third of the Central Cordillera due to logging, urbanisation and expansion of agriculture (L. Heaney in litt. 2019). However, the central and northern portions of the range have been less impacted, with some formerly logged and farmed areas beginning to regenerate (L. Heaney, pers. obs, 2010-2019). As a result, the amount of forest in the Cordillera may have stabilised or even be increasing overall (L. Heaney in litt. 2019). Remote sensing data also indicate that forest loss has been minimal (<1%) within the past three generations (Global Forest Watch 2024, using data from Hansen et al. [2013] and methods disclosed therein). Additionally, the species may not be strictly dependent on old growth forest; it has also been recorded in forest with little undergrowth as well as in second growth adjacent to oak-dominated primary forest (Poulsen 1995, Allen 2020). In the absence of evidence for any declines or substantial threats therefore, the population trend is suspected to be stable overall.

Distribution and population

This species is endemic to the mountains of northern Luzon in the Philippines, where it is known from several sites in the Cordillera Central and from Mt Los Dos Cuernos in the Sierra Madre.

Ecology

It inhabits the understorey of montane or mossy forest above 950 m (principally above 1,400 m), apparently favouring thick, shady patches in areas dominated by oaks (Allen 2020). However, it has also been recorded in forest with little undergrowth and also in second growth adjacent to oak-dominated primary forest (Poulsen 1995, Allen 2020).

Threats

Forest cover has declined substantially in the past due to conversion to agricultural land, primarily for vegetable production (M. Poulsen in litt. 2007, 2012), with selective logging an additional threat. However, remote sensing data indicate that forest loss has been minimal (<1%) in the past three generations (Global Forest Watch 2024, using data from Hansen et al. [2013] and methods disclosed therein). This species may continue to be affected locally by deforestation and degradation particularly in the southern third of the Central Cordillera due to logging, urbanisation and expansion of agriculture (L. Heaney in litt. 2019). However, the central and northern portions of the range have been less impacted, with some formerly logged and farmed areas beginning to regenerate (L. Heaney, pers. obs., 2010-2019). As a result, the amount of forest in the Cordillera may have stabilised or even be increasing overall (L. Heaney in litt. 2019).

Conservation actions

Conservation Actions Underway
No targeted conservation actions are known for this species, however at least part of its range lies within protected areas.

Conservation Actions Proposed
Conduct surveys using mist-nets to determine its current distribution and status in the Cordillera Central and the Sierra Madre mountains, as well as in other sites where the species may occur. Propose further known key sites, including Mt Polis, for establishment as formal protected areas.

Identification

19 cm. Large, vividly patterned, skulking flycatcher. Olive-brown head and upperparts, rufous-fringed wings and tail. Prominent bright white supercilium and throat. Dark rufescent-brown sides of throat and breast-band, bright burnt-orange flanks, white belly and undertail-coverts. Similar spp. Eye-browed Thrush Turdus obscurus superficially similar but has very different behaviour, paler, greyer head and lacks dark breast-band. Voice Not well known but thought to utter thin high-pitched phrases. Hints Skulking and seldom seen. Most likely to be located by song.

Acknowledgements

Text account compilers
Vine, J.

Contributors
Heaney, L. & Poulsen, M.


Recommended citation
BirdLife International (2024) Species factsheet: White-browed Jungle-flycatcher Vauriella insignis. Downloaded from https://datazone.birdlife.org/species/factsheet/white-browed-jungle-flycatcher-vauriella-insignis on 23/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 23/12/2024.