Chimney Swift

How to find it

Plan around migration, since that is the most reliable way to see this swift in Costa Rica. Start in the Caribbean lowlands, especially near the coast, and scan the sky rather than the trees. Look for a dark, cigar-shaped bird with long, narrow, curved wings and quick, stiff, shallow wingbeats. Stormy weather can bring thousands down into feeding flocks over open country. Migrants usually fly high, so expect distant views, and expect big flocks to be easier to pick out than single birds.

How to recognise it

Look for a small, sooty gray swift with very long, slender wings and very short legs.

Silhouette is the best clue:

- a tiny, dark, cigar-shaped body

- curved wings

- stiff, shallow wingbeats

- a short tail that is hard to notice in flight

Its upperparts are the most evenly colored of the Chaetura swifts, with little contrast between back and rump.

Swallows are a useful comparison. They have broader, triangular wings and a tail that is easy to see, while the Chimney Swift has long, narrow, curved wings and a tail you will barely notice. It hunts insects over rooftops, fields and rivers.

What it sounds like

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

Behaviour and diet

This swift spends almost its whole life in the air and feeds on flying insects. It cannot perch. When it rests, it clings to vertical surfaces such as chimney walls, hollow trees or caves.

During passage through Costa Rica, stormy weather can pull thousands into feeding flocks over open country, where they sometimes mix with other swifts. Almost always, you will see it in flight.

Where it lives

In Costa Rica this is a bird of the sky above open country, hunting insects over fields, rivers and rooftops. It is mostly seen on the Caribbean slope, where it is sometimes common to abundant, especially near the coast. Numbers there are patchy, not steady. Migrating birds usually fly high, above about 50 m, so the weather and the timing of passage matter more than the habitat below.

When to see it

Northbound birds pass from mid-March to late April, and spring passage is also listed as running to mid-May. Southbound birds pass from early October to early November. A Costa Rica birding writer calls April a peak month, with large numbers of swallows and Chimney Swifts.

Similar birds

Vaux's Swift looks similar, but it has a paler throat and rump. It is a little smaller and paler, has a slightly different shape, and its calls are higher pitched. Unlike the Chimney Swift, Vaux's Swift stops its migration in Central America. The Costa Rican list also shows Gray-rumped Swift (resident) and Costa Rican Swift (endemic) as Chaetura swifts that could be confused with it.

Names and lore in Costa Rica

The Costa Rican bird list gives the Spanish name Vencejo de Paso. Other Spanish names used for the species are vencejo de chimenea, vencejo pasajero and vencejo espinoso.

Status and conservation

On the Costa Rican list (AOCR) it is a migrant (M), breeding in eastern North America and passing through on the way to South America.

Photography tips

Migrating Chimney Swifts usually fly high, above about 50 m, so expect distant views. Big flocks are easier to see than single birds, so aim for a good migration day and look for the shape of the flock against the sky.