スマトラガマグチヨタカ Batrachostomus poliolophus

A Sumatran endemic, this medium-sized nightbird is limited to foothill and montane forests between 1200 and 2000 meters, only rarely straying to lower elevations. Nocturnal and difficult to see by day as it perches quietly in the middle levels of forest. A relatively short-tailed species, Sumatran has extensive clean white scaling on the underparts. Gives a variety of vocalizations, including an eerily falling whistled trill, as well as various squawks, shrieks, and shorter whistles. Altitudinal range mostly separates it from other small frogmouths, but in situations of potential overlap, note short tail, well-demarcated (not messy) and extensive white scaling on underparts, and different vocalizations.