Plain-brown Woodcreeper

How to find it

Look for army ant swarms in humid lowland forest first. Around a swarm it clings to a vertical trunk or vine, usually 4 to 10 m up, so scan those heights. Listen for the rattle and the sharp stick note. Do not stop at the ants: check mixed-species flocks and monkey troops too, since it does not depend on swarms alone. Birders also say it often drops in to check trees near homes, so gardens beside forest can turn it up.

How to recognise it

This is a medium-sized woodcreeper, 19 to 22.5 cm long, and plain brown overall with no streaks.

Look for these marks:

- a moderately long, nearly straight, black bill

- a slight crest

- rufous tail and wings, a warm contrast with the brown body

- a dark, diffuse malar stripe on the grayish face, its main field mark among Costa Rica's woodcreepers

- chin the same colour as the rest of the underparts, in even olive-brown plumage

Males and females look alike. Juveniles look like adults but have a buff tint on the face and throat and are slightly paler below.

What it sounds like

Recording: Michael Bakker Paiva, CC BY 4.0, source, read 4 Nov 2026.

Behaviour and diet

It regularly follows army ants, clinging upright to trunks and darting out or dropping to the ground to catch insects and spiders fleeing the swarm. It hits bark or wood hard to flush out insects.

It is usually seen alone, but several birds may gather where army ants are swarming. It is not tied to swarms, though. Across its range it is also seen feeding alone, with mixed-species flocks and alongside troops of monkeys.

Where it lives

In Costa Rica it is a fairly common resident of the Caribbean lowlands and foothills, ranging from sea level up to about 750 m, and mostly found below about 900 m. It prefers low and middle levels of humid forest, tall second growth and partly open areas.

It reaches the Pacific side through low passes in the Cordillera de Guanacaste, and it is less common in the drier lowlands south of Lake Nicaragua. One photograph was taken in submontane cloud forest at about 914 m.

When to see it

A Costa Rican natural history page says it breeds from May to August.

Similar birds

Unstreaked woodcreepers can be confused with the Northern Barred-Woodcreeper. The Plain-brown is much smaller, has no barring, shows a dark malar stripe and has a noticeably shorter bill. Elsewhere in its range, its even olive-brown plumage, matching chin and distinct face pattern separate it from the White-chinned Woodcreeper.

Names and lore in Costa Rica

Costa Rica's Spanish name is Trepador Pardo. Elsewhere it is also called trepatroncos fuliginoso, and in Honduras trepatroncos café.

Status and conservation

The AOCR list marks it as a resident (R), and IUCN rates the species Least Concern with a very large range.

Photography tips

Army ant swarms are the best stage, because the bird clings to a vertical trunk or vine, usually 4 to 10 m up, and stays busy there. Watch trunks near the swarm and be ready for it to drop to the ground or dart out after prey.