Vaux's Swift

How to find it

Evening is a good time to watch. At dusk, swifts circle around a known roost tree at Wilson Botanical Garden, which gave a tour group good views. Middle elevations were where most birds were seen on a January 2023 tour. The same tour had a vocal bird along the road to Esquinas, so listen for the twittering calls. Scan the sky over forest, pastures and towns, since it hunts over both forest and more open areas. Whenever you can, try for a good view of the rump.

How to recognise it

Look for a very small swift, small even among its Chaetura relatives.

Shape: a cigar-shaped body, curved wings and a short, blunt, squared tail. It looks swallow-like and seems to have no tail at all.

Colour: mostly glossy black, with the rump and breast a dull dark grayish brown.

Throat: pale gray.

Bill and feet: black.

Its pale, dull underparts and small size help separate it from other swifts. Against Chimney Swift, a similar small, evenly dark swift that passes quickly through Central America, Vaux's has a paler throat and rump.

What it sounds like

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

Behaviour and diet

Vaux's Swift is social and often travels in flocks of 30 or more. It sometimes joins other swifts, such as White-collared Swifts. Its flight mixes stiff wingbeats with wobbly glides, a useful clue when the light is poor.

It feeds in the air on ants, termites, bugs, flies and wasps, so watch the sky rather than the branches.

Where it lives

A Costa Rican bird site says it lives in pastures, cities and forests, and calls it the common black swift of the highlands. Across its range the species uses dry, moist lowland and moist montane forest, and it also uses heavily degraded former forest.

On a January 2023 tour in Costa Rica, Vaux's Swifts were mostly seen at middle elevations.

Similar birds

Costa Rican Swift is the look-alike to check. It has a broader, darker rump band and a clear pale throat patch, and Vaux's looks very similar unless you get a good view of the rump. A Costa Rican guide suggested counting the spiny tail-feather tips on a photo, saying Costa Rican Swift shows about two and Vaux's four or more. Wing shape also matters.

Names and lore in Costa Rica

The official Costa Rican Spanish name is Vencejo Común, and a Costa Rican bird site also gives Vencejo Grisáceo. Elsewhere in Spanish it is called vencejo de Vaux, vencejo de lomo marrón or vencejo lomimarrón.

Status and conservation

The official Costa Rican bird list marks it as a resident species (R), and the IUCN lists it as Least Concern.

Photography tips

Evening is a good time to watch, when swifts circle around the roost tree at Wilson Botanical Garden at dusk. For identification, a photo that shows the rump and the spiny tail-feather tips will help.