The Mountain Thornbill is endemic to the Wet Tropics region.
It is restricted to upland rainforests, where it forages about the foliage of trees and shrubs.
Its calls and behaviour are similar to the drab northern counterpart of the Brown Thornbill.
The Mountain Thornbill was earlier regarded as a subspecies of the Brown
Thornbill, but then distinguished as a separate species in 1969. The most tangible
difference between the two species is the distinctive white eyes of the Mountain
Thornbill.
Its breeding season is from August to February / March.
The nest is a compact dome shape made from fine grasses and fibres and decorated with mosses and
lichens on the outside. It was not until 1971 when the nest was first discovered, and eggs were not described until a few years later.
It is moderately common round Chambers Wildlife Rainforest Lodge but is most
numerous in the highest uplands.