Symposiachrus brehmii (Schlegel, 1871)

Bishop, K. David, 2023, The avifauna of Biak Island, Papua, Indonesia with comments on status, conservation, natural history and taxonomy, Bulletin of the British Ornithologists’ Club 143 (1), pp. 3-62 : 49-50

BIAK MONARCH Symposiachrus brehmii # RR, Endangered

Range Biak, Supiori.

Status Endemic species. Rand & Gilliard (1967) stated that ‘it seems a very rare bird, at least in collections, and to have been met with by few naturalists’. The holotype was collected by von Rosenberg in March 1869 on Supiori (Schlegel 1871, von Rosenberg 1875). In May 1875 a male was collected at Korrido by Beccari (Salvadori 1875). Not met with by Ripley ( Mayr & Meyer de Schauensee 1939). Until 1982 only the adult male ( Fig. 13 ) had been described. On 8 July 1982 KDB observed a bird in a lichen-covered, limestone river-bed at c. 40 m in dense lowland forest on the south coast of Supiori. A characteristic, grating monarchine flycatcher-type call was heard and eventually KDB had a clear view of a large, bold, chunky monarch. Its overall plumage was jet black with a large white throat and upper breast patch. The relatively long tail was edged orange-brown as were the coverts and flight feathers, forming an incomplete patch. We suggest that this was the previously undescribed female or juvenile plumage. The bird was constantly active, moving between perches, hawking and hover-gleaning in the subcanopy c. 10 m up. In January 1997 SvB observed a male in a mixed flock with a female Carterornis chrysomela , two Dicrurus bracteatus , Rhipidura rufiventris and Biak Leaf Warbler Seicercus misoriensis . Thereafter the species was very rarely seen until c.2000 when visitors to Biak greatly increased and local guides learnt where to find it. Although recorded in well-developed lowland forest in southern Biak and primary lowland forest on Supiori, we postulate that this scarce species prefers hill forest and is best searched for in mixed flocks of insectivores. Categorised as globally Endangered by BirdLife International (2021) we concur with Beehler & Pratt (2016) that it may be better classified as Vulnerable.

Breeding 9 July 2009: family party including two young in south-east Biak (Brickle & Tizard 2009).

Figures

Figure 13. Male Biak Monarch Symposiachrus brehmii, Biak, 5 July 2017 (© Daniel Lopez-Velasco)