The Sumatran blue robin is an Old World flycatcher in the family Muscicapidae. It is endemic to the Indonesian island of Sumatra. It was formerly considered a subspecies of the Javan blue robin, with the two being united under the name Sunda robin, but a 2020 study found them to represent distinct species. M. sumatrana can be physically distinguished from M. diana by its much darker plumage in both males and females.
Region
Southeast Asia
Typical Environment
Confined to the Barisan mountain range of Sumatra, it inhabits mature montane evergreen and mossy forests. It favors shaded understory with dense shrub layers, root tangles, and ferny banks along streams and ravines. Birds are typically low to the ground, moving between perches and leaf litter patches while foraging. It tolerates light disturbance but is most frequent in intact forest and older secondary growth.
Altitude Range
900–2500 m
Climate Zone
Highland
Ease of Keeping
Beginner friendly: 1/5
An Old World flycatcher endemic to Sumatra, this species was split from the Javan blue robin in 2020 after vocal and plumage differences were confirmed. Males are notably darker, deep cobalt-blue compared to their Javan counterparts, and females are also duskier overall. It keeps to shaded montane forest understory, often near streams and mossy gullies, where it can be surprisingly skulking.
Temperament
secretive and territorial
Flight Pattern
short rapid wingbeats between low perches
Social Behavior
Usually solitary or in pairs within well-defined territories. Nests are presumed to be cup-shaped and placed low on banks, roots, or ledges, as in close relatives; both sexes likely participate in care of the young. Often associates loosely with mixed-species understory flocks while foraging.
Migratory Pattern
Resident
Song Description
Song is a series of thin, high-pitched, musical whistles with short pauses, sometimes delivered from concealed perches. Calls include sharp tsip notes and soft, sibilant contact calls in the understory.
Plumage
Male is a deep, dark cobalt-blue above with slightly paler blue underparts and a subtly darker facial mask; wings and tail are dusky blue-black. Female is dark brown to olive-brown with faint bluish tones on the tail and slightly paler underparts. Both sexes lack wing bars and appear darker overall than Javan blue robin.
Diet
Feeds primarily on insects and other small arthropods, gleaning from leaves, mossy trunks, and the forest floor. It picks prey from low foliage and sallies short distances to catch flushed insects. Occasional small berries may be taken, but animal prey dominates.
Preferred Environment
Forages in shaded understory, especially along stream gullies, damp banks, and mossy ravines. Often works close to the ground where leaf litter and root tangles provide cover and prey.
