NT
Chestnut-rumped Babbler Stachyris maculata



Justification

Justification of Red List category
This species is widespread and relatively common, occurring within secondary and logged forest habitats. However, it occurs predominantly within the plains-level lowlands, and is therefore at increased risk from wholesale habitat clearance and may be declining moderately rapidly. It is therefore considered Near Threatened.

Population justification
The global population size has not been quantified, but the species is described as generally common in primary forests, but less abundant in secondary forests, and is extinct in Singapore (del Hoyo et al. 2007).

Trend justification
Remote sensing data indicate a relatively rapid rate of forest loss, equivalent to c.20% over three generations (Global Forest Watch 2021). A continuing decline is inferred from forest degradation, owed to clearance for logging, land conversion for agriculture and fires (Collar and Robson 2020). Although the species is known to occur in logged and secondary forests, it is thought to be in far less abundance than primary forest (D. Edwards in litt. 2020). As such, the scale of damage from forest clearance is thought to have been previously overlooked (D. Edwards in litt. 2020). In a comparative study of understorey babblers in the Sundaic region, Styring et al. (2016) found densities of 4.3 individuals/ha in continuous natural forest, 3.6 individuals/ha in logged native forest fragments, 6.1 individuals/ha in mature plantations and 3.6 individuals/ha in young (<5 years old) plantations, but none were found in oil palm plantations. This suggests the impact of forest clearance may be mitigated partly by the increase in plantation area, however Edwards et al. (2010) and Hamer et al. (2015) found that while present, birds occurred at half the density in twice-logged forest than in unlogged forest: hence a very significant population decline may be masked if judged on presence alone. Rates of deforestation have been rapid within the range, and much of this has been absolute clearance of intact forest and replacement with unsuitable oil palm. This species is therefore suspected to be declining, and continue to decline, at a relatively rapid rate of 20-29% over three generations (11.4 years; Bird et al. 2020).

Distribution and population

Stachyris maculata occurs in the Sundaic lowlands, from peninsular Thailand, Sabah, Sarawak and Peninsular Malaysia, Singapore (formerly), Kalimantan and Sumatra, Indonesia and Brunei. It is generally common within suitable habitats across this range.

Ecology

This species is found in broadleaved evergreen forest, including primary forest, peat swamps, and heath forests. It also occurs in overgrown plantations, secondary and logged formations, although in reduced abundance at c. 20-25% less than original density (D. Edwards in litt. 2020). Hamer et al. (2015) found that while present, birds occurred at half the density in twice-logged forest than in unlogged forest, and in a comparative study of understorey babblers in the Sundaic region, Styring et al. (2016) found densities of 4.3 individuals/ha in continuous natural forest, 3.6 individuals/ha in logged native forest fragments, 6.1 individuals/ha in mature plantations and 3.6 individuals/ha in young (<5 years old) plantations, but none were found in oil palm plantations. It is largely restricted to lowlands, with an upper limit of 800 m.

Threats

Rates of forest loss in the Sundaic lowlands have been extremely rapid (Global Forest Watch 2021), owing partly to the escalation of illegal logging and land conversion, with deliberate targeting of all remaining stands of valuable timber including those inside protected areas. Forest fires have also had a damaging effect (particularly in 1997-1998). As this species persists in secondary and logged forests, and plantations however, it may not be under immediate threat from selective logging and may be relatively secure in areas where habitat clearance is incomplete. However, it appears to be intolerant of the oil palm plantations that proliferate the Sundaic region, and there are indications that it may not persist long-term in fragmented patches of secondary forest.

Conservation actions

Conservation Actions Underway
No targeted conservation actions are known for this species, although it does occur in several protected areas, including; Danum Valley Conservation Area (Sabah), Berau district forest (east Kalimantan), Similajau National Park (Sarawak), Tanjung Puting National Park (south Kalimantan), Gunung Leuser and Way Kambas National Park (Sumatra), as well as the now destroyed Padang-Sugihan Wildlife Reserve (south Sumatra) (Collar and Robson 2020). 

Conservation Actions Proposed
Continue to monitor population and habitat trends throughout the range. Conduct ecological studies to determine its response to habitat fragmentation. Effectively protect significant areas of suitable forest at key sites, in both strictly protected areas and community-led multiple use areas.

Acknowledgements

Text account compilers
Fernando, E.

Contributors
Benstead, P., Edwards, D., Gilroy, J. & Taylor, J.


Recommended citation
BirdLife International (2024) Species factsheet: Chestnut-rumped Babbler Stachyris maculata. Downloaded from https://datazone.birdlife.org/species/factsheet/chestnut-rumped-babbler-stachyris-maculata on 22/11/2024.
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 22/11/2024.