Mangrove Vireo

How to find it

Scan low, short red mangroves rather than tall forest, and look in the lower growth. Birders on a mangrove boat trip along the Rio Tarcoles used playback in the main channel to draw the vireo out. Another group found it during a short stop at a mangrove swamp near a restaurant at Caldera, south of Puntarenas. Because it feeds low, alone or in pairs, watch for movement close to the water and listen for the scratchy "chi" notes. A Guanacaste dry-forest day can also begin in mangroves, where guides search for it alongside Northern Scrub-Flycatcher and Panama Flycatcher.

How to recognise it

This is a small vireo, about 11 to 12 cm long, weighing roughly 9 to 13 g. Some forms have a greenish brown crown and face, with a buffy patch above the lores and past the eye.

The Costa Rican subspecies nicoyensis is paler and duller than the other forms. It has an almost pure white throat and belly.

Its iris color varies a lot, from light brown to white, so do not rely on eye color alone. Overall, expect a small, pale bird rather than a bold one.

What it sounds like

Recording: Ryan F. Mandelbaum, CC BY 4.0, source, read 4 Nov 2026.

Behaviour and diet

Along the Pacific coast the vireo usually feeds low above the ground, alone or in pairs. It sometimes joins other species.

Birders have called it elusive, yet also one of the common mangrove specialties. It is present in Costa Rican mangroves but never abundant, so a patient scan of the lower growth is the best way to begin.

Where it lives

On the Pacific coast the vireo is found only in mangrove forest, and it is a specialist of red mangrove, especially small or young trees. In Costa Rica it lives on the Pacific side in the northwest.

The Nicoya Peninsula and the area around the Gulf of Nicoya hold the subspecies nicoyensis. The nominate form pallens reaches the northwest of the country. Costa Rica is the southern end of the Pacific range.

Similar birds

Despite its darker eye, the Mangrove Vireo is thought to be closely related to the White-eyed Vireo. The White-eyed Vireo's song is very different, so voice is a useful way to tell the two apart.

Names and lore in Costa Rica

In Costa Rica and Honduras the bird is called vireo de manglar. Nicaragua uses vireo de los manglares, and Mexico uses vireo manglero. The species was first described from specimens collected at El Realejo in Nicaragua and at Puntarenas in Costa Rica, and Puntarenas is a long-known place for it.

Status and conservation

Resident (R) on the AOCR list; the IUCN rates it Least Concern, and it is described as fairly common within its small Costa Rican range.

Photography tips

Look for it in the lower mangrove growth, where it feeds low above the ground, usually alone or in pairs. Scan low, short red mangroves rather than tall forest. It sometimes joins other species, so a mixed group of small birds is worth checking.