VU
Black Partridge Melanoperdix niger



Justification

Justification of Red List Category
The continuing rapid reduction in the extent and quality of its habitats across much of this partridge's range is suspected to be causing a rapid population decline, qualifying it as Vulnerable.

Population justification
The population size has been previously suggested to fall into the band 10,000-19,999 mature individuals, based on a relatively high population density from related species (10 individuals per square kilometer) and an estimated low occupied proportion of the mapped range. However, there is much uncertainty in this population size. Given that there are so few recent records of the species it appears that the density used may be unrealistically high. There is no direct density estimate, primarily because encounters are so rare, despite considerable ornithological effort in multiple areas of expected occurrence. While it is a very unobtrusive species, whose vocalisations are confusing and have been poorly-known until recently (van Balen & Fischer 2016), this evidence points to occurrence at a very low density or very patchily in the available forest habitat. Noting that it is classified in a monotypic genus, inference from other species may be unwise. In addition, remapping the species's range indicates that the potential area of suitable habitat is smaller than previously judged, and occupancy is still likely to be very low in this newly estimated extent. There remains a relatively large area of potentially occupied habitat on Borneo, but that in Peninsular Malaysia and Sumatra now appears to be small. As such, it is suspected that the current population size could be smaller than that previously estimated, potentially much smaller. As such a new global population estimate is a high research priority for the species.

None have been observed in Peninsular Malaysia for more than a decade (eBird 2021, D. L. Yong in litt. 2021, GBIF.org 2021), despite searches, and here the population is likely to be small or very small. The area of intact forest remaining in 2020 contiguous with forest containing records of the species since 1980 is c. 2,300 km2, based on the remnant intact forest after the application of the plantation layer (Peterson et al. 2016, Harris et al. 2019) and forest cover loss since the production of this layer (data from Global Forest Watch 2021). 

There are recent records in the few larger remnants of dense peat-swamp forest on Sumatra (eBird 2021, GBIF.org 2021), but the extent of forest cover loss here has been very rapid. Current apparently suitable forest here has an extent of 11,087 km2, (estimated as above). On the island of Borneo, a similar forest extent assessment results in potentially over 240,000 kmremaining potentially suitable habitat. However, it is unclear what proportion is actually suitable for the species as it has only been recorded at a handful of widely spaced sites on Borneo, and much of this area may actually be degraded logged forest.

Trend justification
Rates of forest loss in the Sundaic lowlands have been extremely rapid, with total forest cover loss within suitable elevations in the range of the species estimated at 32.9% over the 14 years between 2006-2020 (data from Global Forest Watch 2021). This rate of deforestation is suspected to have driven a rapid population decline in this species, which is expected to continue and may slightly accelerate: average annual rates of forest loss have increased such that projecting the average annual rate for the past five years results in a 34.3% forest cover loss over the next three generations.

Distribution and population

Melanoperdix niger is known from Peninsular and East Malaysia (including both Sabah and Sarawak), and Kalimantan and south Sumatra, Indonesia. It is described as local and sparse to uncommon in Peninsular Malaysia, and there are recent records from at least three sites in Kalimantan and one in Sumatra. It seems scarce and patchy in distribution, although it is easily overlooked owing to a previous lack of information on vocalisations and its elusive behaviour (B. van Balen in litt. 2012). As a result, its distribution and population status are generally very poorly known across its entire range. It is presumably declining because of rapid on-going reductions in its habitat.

On Peninsular Malaysia, the area of intact forest remaining with records of the species since 1980 (GBIF.org 2021) is c. 2,300 km2, based on the remnant intact forest after the application of the plantation layer (Peterson et al. 2016, Harris et al. 2019) and forest cover loss since the production of this layer (data from Global Forest Watch 2021). There are recent records in the few larger remnants of dense peat-swamp forest on Sumatra (eBird 2021, GBIF.org 2021), but the extent of forest cover loss here has been very rapid. Current apparently suitable forest on Sumatra has an extent of 11,087 km(estimated as above). On the island of Borneo, a similar forest extent assessment results in potentially over 240,000 km2 potentially suitable habitat remaining. However it is unclear what proportion is actually suitable for the species: it has only been recorded at a handful of widely spaced sites on Borneo, and much of this area may actually be degraded logged forest, in which Black Partridge seems to be absent. 

Assuming that the species is still present in Peninsular Malaysia and widely (though patchily and at low density) on Borneo, a minimum convex polygon around the range encompasses an area of 1,560,000 km2. Within this, the sum of the area estimated to remain potentially suitable forest within suitable elevation is 256,500 km2, 95% of which is on Borneo and much of which may not actually be suitable habitat. Over the past three generations, between 29.4% (year 2010 forest extent estimate at 75% canopy cover) and 33.8% (year 2000 forest extent estimate at 75% canopy cover) forest cover has been lost from within the elevation range of the species (data from Global Forest Watch 2021). The most recent 5-year annual rate of forest loss is equivalent to a three generation past and future rate of 29.8-34.6% (data from Global Forest Watch 2021). This is considered to be equivalent to the rate of continuing decline in the area of suitable habitat for the species, as all sightings are from intact primary forest (mostly lowland peat forest) with high percentage canopy cover.

Ecology

In Peninsular Malaysia, it is judged to be a lowland specialist, where it has a proclivity for primary or mature, regenerated, closed-canopy evergreen forest on alluvial soils. In Indonesia, it has been recorded in peatswamp forest, and historically was described as inhabiting brushwood and high bamboo-jungle. Recent evidence from Borneo suggests that it probably extends up to at least 900 m, perhaps occasionally up to 1,200 m, but the specific habitat requirement at these elevations is unknown.

Threats

The overriding threats are habitat loss, degradation and fragmentation as a result of large-scale clearance for plantations of oil-palm and to a lesser extent rubber and timber. The conversion of habitat is typically preceded by commercial logging, which targets all remaining stands of valuable timber, even within protected areas. Rates of forest loss in the Sundaic lowlands have been extremely rapid and have been around 30% over the past three generations (14 years). Associated impacts of forest loss such as degradation and increased access for hunting may be having additive impacts on the rate of reduction, but this is uncertain for this very poorly known species. Drought fires appear to be increasing in frequency and severity on Sumatra and Borneo and a more general drying of lowland forest would be suspected to have further negative impacts on the species. Hunting for food may pose an additional, more localised, threat.

Conservation actions

Conservation Actions Underway
It is known to occur in at least six protected areas: Taman Negara and Krau Wildlife Reserve (Peninsular Malaysia), Kinabalu National Park (Sabah), Gunung Mulu National Park (Sarawak), Tanjung Puting National Park and Gunung Palung Nature Reserve (Kalimantan), and Berbak Game Reserve (Sumatra). It also occurs in Pasoh Reserve Forest in Peninsular Malaysia.

Conservation Actions Proposed
Afford the species full protection under Indonesian and Malaysian law. Conduct research into its ecology and habitat requirements. Identify and record its vocalisations to aid field surveys. Identify remaining suitable habitat tracts, and conduct extensive field surveys and village interviews within these areas to clarify its current distribution and population status. Following surveys, review whether key populations are adequately represented within the existing protected areas network, and advocate protection of further areas if necessary. Develop support mechanisms for key Important Bird Areas (IBAs) in Peninsular Malaysia.

Identification

c.24-27 cm. Black (male) or chestnut-brown (female) partridge with distinctive short, stout bill. Male wholly black, female rich chestnut-brown with variably paler (creamy) throat and belly/vent, and blackish bars across inner secondaries. Both have grey legs and feet. Similar spp. Male Roulroul Rollulus rouloul has white crown-band, red crest and red legs. Ferruginous Wood Partridge (Caloperdix oculea) has brighter rufous plumage than female with bold black-and-white markings on upperparts and flanks. Arborophila partridges are duller with less uniform body plumage. Voice Poorly known, but reportedly utters double whistle similar to R. rouloul, and low creaking sound. Hints Shy, typically sits tight until approaching human within few metres, then runs away.

Acknowledgements

Text account compilers
Martin, R.

Contributors
Wells, D.R., van Balen, B.S., Eaton, J., Keane, A., Bird, J., Taylor, J., Benstead, P., Davidson, P. & Yong, D.


Recommended citation
BirdLife International (2022) Species factsheet: Melanoperdix niger. Downloaded from http://www.birdlife.org on 27/06/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 27/06/2022.