NT
Black-and-white Bulbul Microtarsus melanoleucos



Justification

Justification of Red List category
This forest-associated species is listed as Near Threatened because it is suspected to be undergoing a moderately rapid decline (20-29% over three generations) owing to the extensive loss of lowland forests from large areas of the Sundaic lowlands.

Population justification
The global population size of this species has not been quantified, but it is evidently scarce and probably highly nomadic in response to fruiting events (Wells 2007, Eaton et al. 2021, eBird 2024) in remaining tracts of lowland forest, which remain widespread, although much reduced in extent compared to three generations ago. Accordingly, its global population size is likely to be relatively large.

Trend justification
No direct population trend data are available for this species, however remote sensing data are considered a suitable proxy for this forest-dependent species. Over the past three generations, forest cover within its range reduced by c. 18-22% (Global Forest Watch [2024], based on data from Hansen et al. [2013] and methods therein). This species is commonest at lower elevations, where rates have been most rapid, and the species may be additionally impacted by forest degradation and fragmentation. Accordingly, rates of population reduction may be slightly higher than remote sensing data alone indicate. Accordingly, the rate of population reduction for the past three generations is set at 20-29%.

Distribution and population

Microtarsus melanoleucos is confined to the Sundaic lowlands, where is it known from peninsular Thailand, Sabah, Sarawak and Peninsular Malaysia, Singapore (where rare and only sporadically seen), Kalimantan and Sumatra (including Mentawai ), Indonesia and Brunei (BirdLife International 2001).

Ecology

This species occurs in broadleaved evergreen forest (including selectively logged forest), mixed-dipterocarp forest, secondary growth and forest edge, from lowlands up to at least 1,500 m but recorded to 3,050 m (Eaton et al. 2021). It is also recorded from luxuriant gardens and cultivation, peatswamp forest and overgrown plantations. Its nomadic tendencies suggest a degree of specialisation in its foraging niche, although further research is needed to determine its habitat requirements.

Threats

The chief threat to this species is forest loss, which has been especially rapid in the Greater Sundaic bioregion due to timber extraction and the proliferation of plantations (chiefly oil-palm and rubber). These threats are thought to have driven declines of more than 20% over the past three generations. Forest fires associated with climate change may become more frequent over time, adding an additional pressure to this species including in protected areas. There is no evidence, however, that the species is heavily trapped.

Conservation actions

Conservation Actions Underway
This species occurs in numerous protected areas across its range, which safeguard it from more precipitous rates of population decline. No specific measure is known.

Conservation Actions Proposed

Continue to monitor rates of population decline using habitat extent as a proxy. Protect more areas of lowland forest. Instigate longer-term monitoring at some sites to determine whether there are additional threats to habitat loss.

Acknowledgements

Text account compilers
Richardson, L., Berryman, A.


Recommended citation
BirdLife International (2024) Species factsheet: Black-and-white Bulbul Microtarsus melanoleucos. Downloaded from https://datazone.birdlife.org/species/factsheet/black-and-white-bulbul-microtarsus-melanoleucos 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.