The grey thornbill, ashy gerygone or mountain gerygone is a species of bird in the family Acanthizidae. It is found in the New Guinea Highlands. Its habitat includes subtropical and tropical moist montane forests.
Region
New Guinea Highlands
Typical Environment
Occurs along the Central Range of New Guinea in subtropical and tropical moist montane forests, including mossy cloud forest, forest edges, and secondary growth. It forages from the understory to mid-canopy, often along vine tangles and bamboo. The species tolerates selectively logged areas if sufficient understory and mid-story structure remain. It is typically absent from lowland rainforest and open grasslands.
Altitude Range
900–2800 m
Climate Zone
Highland
Ease of Keeping
Beginner friendly: 1/5
Also known as the ashy gerygone or mountain gerygone, this tiny passerine belongs to the Australasian family Acanthizidae. It inhabits the montane forests of New Guinea, where it actively gleans insects among foliage. Like other gerygones, it builds a neat, domed, hanging nest with a side entrance. Its high, tinkling calls can carry surprisingly far through mossy forest.
Temperament
active and somewhat skulking
Flight Pattern
short rapid wingbeats with brief flits between perches
Social Behavior
Usually encountered singly, in pairs, or in small family groups, and it often joins mixed-species flocks. Pairs are likely monogamous and defend small territories during breeding. The nest is a domed, pendant structure suspended from fine branches or vines, with a side entrance and lining of soft plant fibers.
Migratory Pattern
Resident
Song Description
A high, tinkling series of thin notes that may accelerate into a light warble. Contact calls are soft, high-pitched seeps that carry through dense foliage without being loud.
Plumage
Soft, ashy-grey upperparts with paler grey to off-white underparts and a clean whitish throat; wings and tail slightly darker with subtle pale edging. Overall appearance is plain and smooth-textured, aiding camouflage in shaded montane foliage.
Diet
Primarily small insects and other arthropods such as spiders and caterpillars. It gleans prey from leaves, twigs, and mossy substrates and occasionally hover-gleans to snatch items from leaf undersides. Foraging is deliberate but continuous, covering short distances with frequent pauses to inspect foliage.
Preferred Environment
Feeds within the understory and mid-canopy of moist montane forest, especially along edges, vine tangles, and bamboo thickets. It also uses secondary forest and shrubby regrowth when structure is suitable.
