Wedge-tailed Grass-Finch

How to find it

Start with the right grassland: tall grass in the Térraba region of the southwest. Males sing from fairly open spots such as a fence post or the top of a shrub, and this is the best chance of a view, because the bird otherwise stays low in grass tufts. Listen for the sweet double whistle, then scan the exposed perches. At Alto Salitre a pair passed a parked car and then sang from tall grass, so slow driving with stops to listen can pay off. One trip report needed a second morning in the Salitre savannas and then saw about 6 in the same areas checked the day before, so plan for more than one visit. If a bird is flushed, watch for a low flight with a flicking tail and a drop back into cover.

How to recognise it

Above, the bird is brown with heavy black streaks. The wings are dusky with a yellow bend, the throat is white and the breast is light brown, over cream underparts. The bird is about 18 cm long.

The bill is two-toned: mostly black above, with the cutting edge and lower mandible bright yellow. The legs are pale brown to flesh colour.

The tail is the feature that stands out: very long, strongly graduated and stepped, with pointed, very thin feather tips. A Costa Rican account compares it to the tail of a spinetail (Synallaxis).

Young birds are richer in colour above, with buff and blackish streaking, and their eyebrow and underparts are pale yellow.

What it sounds like

Recording: Laura Veronica Bianchi, CC BY-SA 4.0, source, read 4 Nov 2026.

Behaviour and diet

The grass-finch forages on the ground for insects and seeds, and it lives in pairs and family groups. Away from its singing perch it is secretive and works low in grass tufts.

When startled it flies low over the vegetation, flicking its tail up and down, and then drops back into cover.

The nest is a cup of dry grass set in grass, between ground level and about 30 cm high. It holds 2 white eggs.

Where it lives

This is a bird of damp to fairly dry grassland with scattered shrubs, and it strongly prefers tall grass wherever it occurs. In Costa Rica it uses savannas with scattered trees and shrubs, and it is most common where the grass is tall and not heavily grazed or burned.

It is a resident of the Térraba region on the southern Pacific slope, in the southwest. A Costa Rican account gives an elevation range from 150 m to about 450 m, though the upper figure is partly inferred. Another account says it reaches about 800 m in the country.

When to see it

Breeding in Costa Rica runs from May to September, based on gonad data and juveniles seen. The species is a sedentary year-round resident.

Similar birds

The Lesser Grass-Finch looks almost the same, but it has a grayish face and streaked flanks. Its rasping, chattering song is quite unlike the sweet whistles of the Wedge-tailed. That comparison comes from South America, not Costa Rica, so song and a good look at the face are the clues to use.

Names and lore in Costa Rica

In Costa Rica the bird is called sabanero coludo or chicharrón. Elsewhere Spanish speakers use other names: coludo grande in Argentina, Paraguay and Uruguay, pinzón-yerbero colicuña in Panama, and sabanero cola de cuña in Peru.

Status and conservation

The AOCR list marks it as a resident (R), and the IUCN rates the species Least Concern overall, though in Costa Rica it is considered threatened locally and protected by wildlife law.

Photography tips

Patience with a long lens is the approach that has worked. One Costa Rican photographer got a bird at the Alto Salitre savannas with a 600 mm lens, after a pair passed the car and then sang from tall grass. Singing males on fence posts or shrub tops offer the clearest chance.