Lineated Foliage-gleaner

The Lineated Foliage-gleaner, Syndactyla subalaris, is a modestly sized bird, measuring 17 to 19 cm in length and weighing between 26 to 40 grams. Both sexes don a similar plumage, characterized by a blend of dark and light hues, with a distinctive buff supercilium and a rich dark brown back adorned with buff streaks. The tail is a dark chestnut, and the wings bear a rufescent brown tinge. The bird's underparts are streaked with buff, fading towards the rear, and the undertail coverts are a paler brown with ochraceous streaks.

Identification Tips

To identify the Lineated Foliage-gleaner, look for its discontinuous light buff supercilium, blackish brown face with buff markings, and dark brown crown with thin buff streaks. The species exhibits a narrow, ill-defined darker brown collar with wide buff streaks. The throat is buff with blurry brownish streaks, transitioning to a dark brown breast with buff streaks. The iris is typically brown to dark brown, the maxilla dark brown to black, and the mandible ranges from grayish horn to ivory.

Habitat

This bird prefers evergreen forests in subtropical and foothill zones, often found along streams with dense undergrowth. It thrives at elevations between 1,000 and 2,300 meters, but can be found as low as 600 meters and up to 2,800 meters in Colombia.

Distribution

The Lineated Foliage-gleaner has a disjunct distribution across several countries, including Colombia, Costa Rica, Ecuador, Panama, Peru, and Venezuela. Its range is divided among six recognized subspecies, each occupying different mountain ranges and elevations within these nations.

Behaviour

A year-round resident, the Lineated Foliage-gleaner is typically observed foraging alone or in pairs, and it often joins mixed-species feeding flocks. It forages from the forest understory to mid-levels, gleaning and probing for prey among leaves, moss, and epiphytes, and is known to hang upside down to reach the undersides of branches.

Song & calls

The song of the Lineated Foliage-gleaner is a fast, accelerating series of dry, harsh, scratchy, nasal notes, which can vary in pitch and speed. Its calls are similarly dry and harsh, with a variety of sounds described as "tzuk," "tcheck," "skanh," "jert," or "kr-rk."

Breeding

Details on the breeding season of the Lineated Foliage-gleaner are scarce. It is presumed to be monogamous, with the only fully described nest being a cup of soft fibers on a twig platform, located in a tree hole and containing two eggs. Further aspects of its breeding biology remain unknown.

Diet and Feeding

The diet of the Lineated Foliage-gleaner consists mainly of arthropods, including insects and spiders, and occasionally small vertebrates like frogs and lizards. It employs a methodical approach to foraging, searching among various natural substrates while navigating large branches and vines.

Conservation status

The IUCN has classified the Lineated Foliage-gleaner as Least Concern. Despite a declining population, it boasts a large range and a substantial estimated population of mature individuals. The species is considered uncommon to fairly common within its range and is present in several protected areas.