Bougainville Thrush Zoothera atrigena


Justification of Red List Category
This enigmatic species is classified as Near Threatened because it is thought to have a very small population on a single island, given the very few records but the population is considered to be stable in the absence of plausible threats within its known range.

Population justification
The population is placed in the band 600-1,700 mature individuals, equating to 1,000-2,500 individuals in total. This is based on the area above the minimum altitudinal limit for the species within the species extent of occurrence.

Trend justification
There are no data on population trends and at the altitude of the species it is not considered likely that there are threats operating that would be causing significant population declines; the threat of introduced predators does not seem to be directly applicable, following observations of congeners on Makira persisting alongside a large feral cat population (G. Dutson in litt. 2016).

Distribution and population

Zoothera atrigena is a very infrequently recorded species of Bougainville, Papua New Guinea. It is known only from the type-locality at 1,500 m  in one region in the Crown Prince Range (Hadden 1981, Ripley and Hadden 1982). As with other Zoothera spp., it is a very secretive species and is likely to have been under-recorded. However, it does genuinely appear to have a small total population size.


It has only been recorded from montane forest in the Crown Prince Range above 1,000 m. The subspecies Z. atrigena has been reported to feed in gardens of taro (Araceae crops) within montane forest (Dutson 2011).


The species has a high dependence on primary forest, and so forest loss and degradation may be a low threat, but rates of loss within the altitudinal range of the species are very low (Hansen et al. 2013).

Conservation actions

Conservation Actions Underway
None is known.

Conservation Actions Proposed
Re-discover and survey the subspecies atrigena



Text account compilers
Derhé, M., Dutson, G., Mahood, S. & O'Brien, A.

Dutson, G.

Recommended citation
BirdLife International (2020) Species factsheet: Zoothera atrigena. Downloaded from http://www.birdlife.org on 10/08/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 10/08/2020.