Olive-sided Flycatcher

How to find it

Scan the tops of dead snags and exposed high branches at forest edges and clearings. Look for an upright bird that flies out to catch an insect. It is often very abundant along the Caribbean coast in September and early October. Birders also found it in early September at the edge of cloud forest near Cinchona and Vara Blanca. Once you find a bird hawking from a snag, wait, because it keeps coming back to the same perch.

How to recognise it

This is a large, thick-set Contopus with a sturdy bill and a fairly short tail. It is about 17 cm long and weighs about 32 g. It looks bull-headed, with a slight crest.

The mark to learn is the vest:

- Dark gray sides frame a white stripe down the centre of the breast, so the front looks like an open vest.

- The olive-gray colour runs across the breast.

- From behind, a white patch shows from behind the wing onto the sides of the rump, and white tufts at the rump are sometimes visible.

The upper bill is black and the lower bill is dull orange with a dark tip. The legs are black.

What it sounds like

Recording: julesthebirder, CC BY 4.0, source, read 4 Nov 2026.

Behaviour and diet

It is solitary and territorial. It sits on very high perches and makes long sallies after insects, then returns to the same prominent branch. It perches upright, so the shape is easy to pick out.

It mainly eats flying insects caught in flight, such as bees, wasps, moths and beetles. It may also eat some fruit while migrating or wintering.

Where it lives

During migration in Costa Rica it can turn up almost anywhere, on bare snags and open branches. Migrants are found countrywide, from the lowlands up to about 2500 m, and only rarely as high as 3000 m.

In winter it uses the canopy and edges of forests, savannas, scrub, pastures, gallery forest and tree plantations. It mostly favours edges, clearings and broken canopy of highland forest and semi-open areas. Wintering birds are rare on both slopes, mostly in the foothills and mountains between 600 and 2300 m.

When to see it

Fall passage runs from late August to late October, and spring passage from mid-March to early June. Wintering birds have been reported in January, near La Fortuna on 22 January 2019 and on the La Gamba to Golfito road in late January 2023.

Similar birds

It can be confused with other Contopus pewees, such as Greater Pewee and the wood-pewees. The Greater Pewee has a plain gray breast, unlike the vested pattern of this bird. The white centre stripe between dark sides is the mark to check.

Names and lore in Costa Rica

The official Spanish name is Pibí Boreal, with Tontillo also listed. Elsewhere in Latin America it goes by pibí colicorto in Nicaragua, papamoscas boreal in Mexico, atrapamoscas boreal in Colombia, and mosquero lados olivos.

Status and conservation

The official Costa Rican bird list marks it as M, a migrant, and globally it is rated Near Threatened because its population has been declining.

Photography tips

Scope views are often possible. A bird hawking insects from an exposed snag keeps returning to the same perch, so you can frame the branch and wait for it to come back.