Rufous-throated Fulvetta

The rufous-throated fulvetta is a member of the family Pellorneidae found in south-eastern Asia from the Himalayas through Indochina to south-western Cambodia. Its natural habitat is subtropical or tropical moist lowland forest (Wikipedia, general species account).

That short account is the only source read for the Bhutan guide. It does not name Bhutan specifically, and gives no plumage, size, diet or breeding information, so none is stated.