クロアゴカササギビタキ Symposiachrus boanensis

A striking black-and-white, heavy-billed flycatcher-like songbird confined to Boano Island. Black above, with black head and throat, white collar, and all-white underparts. Note broad white outer tail feathers. Juveniles gray above with buffy underside. Pairs or singles join mixed-species flocks in understory of lowland forest and forest edge. The species lacks a strong peach collar and wash on the breast, unlike Spectacled Monarch. Song is a level-pitched whistle, “sweee,” sometimes followed by a buzzing trill. Also gives harsh, rasping “grrrt” alarm notes and twittering phrases.