Justification of Red List category
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined 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 decreasing, but based on forest loss estimates, the population is not believed to be decreasing sufficiently rapidly to approach the thresholds under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, but due to its common occurrence and high density in degraded habitats, it is not believed 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.
The species was recently split, previously being lumped with Purple-chinned Starling (A. circumscripta) under A. metallica (Collar 2018). The global population size of Metallic Starling has thus not been quantified, but is considered to be generally common across most of its range. The species also occurs at higher densities in secondary habitats such as coconut plantations and mangroves (G. Dutson in litt. 2020). Population density estimates measured at 3 birds/hectare in primary lowland forests and 1-7.5 birds/hectare in degraded lowland habitats and mangroves on Kolombangara (Buckingham et al. 1990) therefore suggest that the overall population may be large and numerous. Recent surveys in New Britain, Papua New Guinea also showed that the species remains common in oil palm plantations, being recorded in 60% of all forests observed (R. Davis in litt. 2020).
The population trend is difficult to determine because of uncertainty over the impacts of habitat modification on population sizes. However, assuming that population declines are occurring at the same rate as forest loss, recent forest loss analysis (per Tracewski et al. 2016, Global Forest Watch 2020) suggests the species is undergoing a decline at a rate of c. 14% over a three-generation period (11.4 years; Bird et al. 2020). Pressures from hunting for food may additionally exacerbate population declines over forest loss alone. However, as the species commonly occurs in plantations and secondary forests however, it is though to be tolerant of some degraded habitats. The rate of decline is therefore tentatively placed in the band of 10-15%.
Aplonis metallica has a wide range extending from east Indonesia, through Papua New Guinea, to the Soloman Islands and south to Queensland, Australia. The species is described as locally common to abundant (especially in lowland forests across the Melanesia Islands; G. Dutson in litt. 2020), although uncommon or rare on the Tanimbar islands and Sulu Islands in Indonesia (Feare and Craig 1998).
The species inhabits lowland areas such as rainforests, coastal woodlands, and mangroves, usually occurring below 1,000 m (Craig and Feare 2020). It is also known to occur across forest edges, clearings, gardens, and savannas. It is therefore thought to be tolerant of some habitat degradation due to commonality in plantations and secondary habitats (G. Dutson in litt. 2020, R. Davis in litt. 2020).
Although forest loss is marginal and the species readily inhabits degraded areas, it may be affected by land clearance for oil palm plantations (G. Dutson in litt. 2020). In New Guinea and parts of Australia, local communities also treat the species as a traditional source of food (Craig and Feare 2020). It is however not thought to be used in the wild bird trade as much as other similar species (Craig and Feare 2020).
Conservation Actions Underway
No targeted conservation actions are known for this species.
Text account compilers
Butchart, S., Davis, R.A., Dutson, G., Eaton, J., Ekstrom, J. & van Balen, B.S.
BirdLife International (2023) Species factsheet: Aplonis metallica. Downloaded from http://datazone.birdlife.org/species/factsheet/metallic-starling-aplonis-metallica on 11/12/2023.
Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://datazone.birdlife.org on 11/12/2023.