Pearled Treerunner

Overview

The pearled treerunner (Margarornis squamiger) is a species of bird in the ovenbird family Furnariidae, native to the Andes of South America. It is classified as Least Concern by the IUCN and is considered a year-round resident throughout its range.

Identification

• Size and weight: Approximately 15 to 16 cm long and weighing between 14 and 19 g.
• Plumage: Features a yellowish buff supercilium, dark brown crown, and bright reddish brown back; underparts are rufescent with oval yellowish spots on the upper breast that stretch out on the belly.
• Tail: The tail is bright reddish brown with feather ends that lack barbs, giving a distinctive spiny appearance.
• Vocalisation: Produces a rapid series of high-pitched, thin 'tick' notes, along with short trills such as 'trrrt-trrrt'.

Habitat

Found in the Andes of Bolivia, Colombia, Ecuador, Peru, Venezuela, and possibly Argentina, this species primarily inhabits montane evergreen and elfin forests, as well as Polylepis woodland and secondary forest. It favours areas heavy with moss and epiphytes at elevations between 1,500 m and 3,800 m, though typically between 2,500 m and 3,500 m.

Diet

Feeds on a variety of arthropods, typically foraging in pairs, small groups, or mixed-species flocks within the mid-storey to canopy of the forest. It acrobatically hitches up trunks and limbs using its tail for support, often gleaning prey from moss, epiphytes, and dead leaves while hanging upside down.

Did you know?

The tail feathers of this bird lack barbs at their ends, giving them a uniquely spiny appearance. It constructs ball-shaped nests with a side entrance by forming moss into a ball, placing them under a limb or rock.