EN
Black-winged Myna Acridotheres melanopterus



Taxonomy

Taxonomic note
Previously split by del Hoyo & Collar (2016) into three species, Black-winged Myna A. melanopterus in most of Java except the far east, Grey-backed Myna A. tricolor in far eastern Java and Grey-rumped Myna A. tertius on Bali. However, genetic analysis by Sadanandan et al. (2020) established that these taxa are very weakly distinguishable genetically, and that the darker coloration of tertius may be due to introgression from Javan Myna A. javanicus. Their recommendation to lump the three species is accepted here. Sometimes placed in genus Sturnus, but appears behaviourally and vocally closer to present genus. Three subspecies recognised. Prior to the 2016, this concept, including the three subspecies as detailed above, was recognised following Sibley & Monroe (1990, 1993).

Taxonomic source(s)
Handbook of the Birds of the World and BirdLife International. 2021. Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 6. Available at: https://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v6_Dec21.zip.
Sibley, C.G. and Monroe, B.L. 1990. Distribution and Taxonomy of Birds of the World. Yale University Press, New Haven, USA.
Sibley, C.G. and Monroe, B.L. 1993. A supplement to 'Distribution and Taxonomy of Birds of the World'. Yale University Press, New Haven, USA.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- C2a(i); D A2d+3d+4d; C2a(i); D1

Red List history
Year Category Criteria
2021 Endangered C2a(i,ii); D
2016 Not Recognised
2015 Critically Endangered A2d+3d+4d
2013 Critically Endangered A2d+3d+4d
2012 Critically Endangered A2d+3d+4d
2010 Critically Endangered A2d; A3d; A4d
2008 Endangered A2d; A3d; A4d
2004 Endangered
2000 Endangered
1994 Lower Risk/Near Threatened
1988 Lower Risk/Least Concern
Species attributes

Migratory status not a migrant Forest dependency low
Land-mass type shelf island
Average mass -
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 164,000 km2 medium
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 150-190 mature individuals medium estimated 2021
Population trend decreasing poor inferred 2014-2024
Rate of change over the past 10 years/3 generations (longer of the two periods) 30-49% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 10-49% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 30-49% - - -
Generation length 2.81 years - - -
Number of subpopulations 3-100 - - -
Percentage of mature individuals in largest subpopulation 1-89% - - -

Population justification: This species forms multiple subpopulations, based on the three distinct subspecies and their distribution throughout its range. Subspecies melanopterus is possibly extirpated in the wild (eBird 2021, Eaton et al. 2021) with recent records attributed to individuals that have either escaped, or are part of ongoing release attempts to re-establish a population (P.G. Akbar in litt. 2021, S. Brusland in litt. 2021). Subspecies tricolor comprises the largest population, with c.180 birds in Baluran National Park (Squires et al. in press., T. Squires in litt. 2021); at Alas Purwo National Park, the population is now estimated to comprise <5 individuals, with no confirmed sightings since two were seen in June 2019 (P.G. Akbar in litt. 2021). Subspecies tertius had previously been estimated at 200 individuals, with 190 estimated to be present within Bali Barat National Park in 2014 (Eaton et al. 2015). More recent estimates suggest 35-100 birds remain (Brillianti et al. 2019, S. Brusland in litt. 2021, J. Eaton in litt. 2021) in the National Park and surrounding areas. Small numbers of this taxon may also persist on Nusa Lembongan. The global population is therefore estimated at 220-285 birds, equivalent to c.150-190 mature individuals. The largest subpopulation, in Baluran National Park, comprises c.180 birds, equivalent to c.120 mature individuals.

Trend justification: From surveys of three of Indonesia's largest open bird markets conducted between 2010-2014, Shepherd et al. (2015) report that on average, 7 Black-winged myna birds were observed per market survey. This is a reduction of roughly 75% compared to market surveys conducted in 1991-1993, when the average was 30 per market survey. This implies that the population has reduced by roughly 75% in c.20 years. Over a 10 year period, this would be equivalent to a rate of decline of 50%. 

Subspecies A. melanopterus is thought to have declined by 80-100% over the 13 years up to 2009 (J. Eaton in litt. 2009) and is now believed to be extirpated in the wild (Eaton et al. 2021) given the demands of the bird trade, as well as the paucity of records in the field. In recent years, very few individuals of A. tricolor have been observed during market surveys. As they still command a high price (S. Chng in litt. 2016), it is likely that this scarcity is due to population declines, rather than a reduction in demand. However, A. tricolor is not as sought after as A. melanopterus (S. Chng in litt. 2016, Nijman et al. 2018), and so the overall rate of decline may not be as high as that for A. melanopterus. While A. tertius remains highly desirable, records from the wild within its now very restricted range indicate that the rate of decline is not as great as that noted in A. melanopterus (Shepherd et al. 2015; S. Chng in litt. 2016). It is therefore not thought that the global population is declining at the same rates reported for A. melanopterus. 

The rate of decline is still thought to be  high, and is suspected to fall into the band of 10-49% over 10 years. It is unlikely that the demands of the bird trade will cease soon, so the rates of decline are suspected to continue into the future.


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
Indonesia extant native yes
Singapore extant introduced yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Indonesia Bali Barat
Indonesia Baluran

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Arable Land suitable resident
Artificial/Terrestrial Pastureland suitable resident
Forest Subtropical/Tropical Dry suitable resident
Savanna Dry suitable resident
Shrubland Subtropical/Tropical Dry suitable resident
Shrubland Subtropical/Tropical Moist suitable resident
Altitude 0 - 2400 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Biological resource use Hunting & trapping terrestrial animals - Intentional use (species is the target) Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Reduced reproductive success, Species mortality
Pollution Agricultural & forestry effluents - Herbicides and pesticides Timing Scope Severity Impact
Ongoing Unknown Slow, Significant Declines Unknown
Stresses
Ecosystem degradation, Reduced reproductive success, Species mortality

Utilisation
Purpose Scale
Pets/display animals, horticulture national, international

Recommended citation
BirdLife International (2024) Species factsheet: Black-winged Myna Acridotheres melanopterus. Downloaded from https://datazone.birdlife.org/species/factsheet/black-winged-myna-acridotheres-melanopterus 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.