The yellow-breasted warbler (Phylloscopus montis) is a species of Old World warbler in the family Phylloscopidae. It is found in Indonesia, Malaysia, and Palawan Island in the Philippines. The species is most common on the islands of Sumatra and Borneo in Indonesia. Its natural habitats are subtropical or tropical moist lowland forest and subtropical or tropical moist montane forest. The species nests in mid-February and breeds February-April. It builds domed nests with a side entrance out of grasses and bryophytes. Nests are found among roots under the overhanging lip of an eroded bank or other similar place. It forages for food alone or with small parties of not more than five birds. (Source: Wikipedia.org, CC BY-SA)