Yellow-green Vireo

How to find it

Listen first, then look up in the foliage. Gardens and open wooded areas in the breeding season are good places to start, since the bird sings while it foraging. Newly arrived birds in March were very vocal, and song on arrival helps you find them. They were most numerous in the Pacific lowlands, especially the drier parts.

Dry country around Carara is a habitat worth checking, and birders have found it in the dry scrubland north of Tárcoles. Along Guacimo Road in the Carara area, a guide drew one in with a pygmy-owl imitation, since small birds often come to check out that sound. Garden grounds, including hotel gardens, can be good places to meet it, and one tour group had its first of the trip in a garden in the Orosi valley.

How to recognise it

This is a fairly large vireo, about 14 cm long, with no wing bars.

Adults show:

- olive green upperparts and whitish underparts

- yellow flanks and breast sides

- a bright yellow undertail

- a gray crown and a pale eyebrow

- red eyes, a brick red in Costa Rica

Young birds have brown eyes and less yellow. Compared with a Red-eyed Vireo, the head is less contrasty and the back is a brighter green. One birder describes the face as a Red-eyed without the black mascara, so the pale eyebrow looks softer. A Costa Rican blog calls the bill largish and mostly pale, and says the face pattern can look somewhat diffuse, with the yellow mostly on the vent and flanks.

What it sounds like

Recording: myrmexflora, CC0 1.0, source, read 4 Nov 2026.

Behaviour and diet

It is active and vocal, and it sings while foraging in trees. It hops and flutters along the outer foliage, often stopping to pick caterpillars and beetles off leaves and twigs. It also eats berries and arilled seeds.

Song fades as the rains approach, then peaks when nesting begins. Breeding in Costa Rica runs March to July. Only the female builds the nest and incubates, and the male helps feed the chicks.

Where it lives

In Costa Rica it uses treetops in clearings, gardens, open groves and savannas, and also the canopy and middle levels of evergreen and deciduous forest. It is less numerous in wetter, heavily forested places, and across its range it is absent from continuous unbroken forest, preferring open country with scattered trees, plantations, forest edges and riverside woods.

The Pacific slope holds the most birds, from the lowlands up to at least 1,500 m. It breeds in forested areas to about 1,524 m. The Caribbean slope has fewer, though it also reaches some highland gardens around Turrialba.

When to see it

It reaches southern Costa Rica in late January or early February and the Central Valley after mid-February or early March. It leaves in mid-October, sometimes mid-November, and winters in western Amazonia.

Similar birds

Red-eyed Vireo has a black line edging its gray crown and a black eye-line, and it lacks the clearly yellow sides and flanks of the Yellow-green. Immature Red-eyeds also show yellow on the flanks and undertail, so that feature alone is not enough. Red-eyeds pass through Turrialba September to November southbound and late March to May northbound. A Red-eyed seen from June to August may be a Chivi Vireo, and both Chivi groups sound different from Red-eyed, so recording any song helps.

Names and lore in Costa Rica

Costa Ricans use Vireo Cabecigrís as the official Spanish name, plus the nicknames Chiguisa, Chuesa, Cazadora and Fraile. Red-eyed Vireo shares the nickname Chiguisa. A regional name list also gives Yué, a Huetar name, for this species in Costa Rica. Other countries differ: Mexico says vireo verdeamarillo and Colombia says verderón verdiamarillo.

Status and conservation

The AOCR list marks it RR,M, and the IUCN lists it as Least Concern, common and abundant over most of its range.

Photography tips

Across its range it stays in the upper tree levels and often moves in shadow, so it is easy to hear but hard to see or photograph well. Follow the song, wait for it to come to the outer foliage, and try a pygmy-owl imitation, which can draw it closer.