Biak Monarch Symposiachrus brehmii


Justification of Red List Category
This species has a very small range and appears to be restricted to unlogged lowland forest, which is severely fragmented and rapidly declining through logging and clearance for agriculture. It is therefore listed as Endangered. However, this classification is based on few data and the species may prove to be more common and widespread.

Population justification
The population is estimated to number 2,500-9,999 mature individuals based on an assessment of known records, descriptions of abundance and range size. This is consistent with recorded population density estimates for congeners or close relatives with a similar body size; the fact that only a proportion of the estimated Extent of Occurrence is likely to be occupied, and the species's rarity as judged by recent surveys. This estimate is equivalent to 3,750-14,999 individuals in total, rounded here to 3,500-15,000 individuals.

Trend justification
This species is suspected to be declining at a moderate rate, in line with the on-going loss of forest on the islands of Biak and Supiori.

Distribution and population

This species is endemic to the twin-islands of Biak-Supiori in Geelvink Bay, West Papua (formerly Irian Jaya), Indonesia (Beehler et al. 1986). It was clearly scarce historically (Mayr and Meyer de Schauensee 1939) and there are only twelve records, including six since 2008 (van Balen in litt. 2012). However, there has been little recent ornithological exploration of the forests of interior Biak-Supiori, where it may prove to be more common and widespread (K. D. Bishop in litt. 2000).


The recent observations are from lowland forest, one bird in a lichen-covered limestone riverbed in thick, lowland rainforest at c.60 m (Bishop 1982), another record from logged lowland forest with a mixture of highly degraded and pristine areas (Gibbs 1993), and a third from a tiny patch of tall forest within secondary growth and plantations (S. van Balen in litt. 2000).


Large areas of forest on Biak have been destroyed or damaged by logging and subsistence farming, particularly the southern plains, and the remainder is under pressure (Bishop 1982, K. D. Bishop in litt. 1996, D. Holmes in litt. 2000). Furthermore, forest does not regenerate easily on areas of raised coralline limestone. Much of Supiori comprises virtually impenetrable, forested limestone mountains, which are likely to be safe from habitat degradation.

Conservation actions

Conservation Actions Underway
There are two protected areas on the islands, Biak-Utara (110 km2) and Pulau Supiori (420 km2) Nature Reserves (Sujatnika et al. 1995).

Conservation Actions Proposed
Conduct surveys on both islands to establish its current distribution, population status and assess its habitat requirements. Afford formal protection to further key sites where appropriate. Control logging on Supiori (Bishop 1982).


17 cm. Striking black, white and pale yellow monarch. Black or dark brown head, throat, mantle, wings and central tail feathers, with white wing-patch, lower breast and belly, rump and outer tail feathers. Variable yellowish-white on head and breast may be sex- or age-related. Similar spp. Male Golden Monarch M. chrysomela is bright golden-yellow with black throat, mantle, tail and flight feathers. Northern Fantail Rhipidura hyperythra has white throat and lacks extensive white on wings, rump and tail. Voice Short rasps. Hints Rarely seen at Warafri, perhaps best to trek into forested hills inland.


Text account compilers
Benstead, P., Bird, J., Crosby, M., Dutson, G., Taylor, J., Allinson, T

van Balen, B., Gregory, P., Bishop, K., Burrows, R., Holmes, D.

Recommended citation
BirdLife International (2019) Species factsheet: Symposiachrus brehmii. Downloaded from http://www.birdlife.org on 26/05/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 26/05/2019.