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July 26, 2026Sources cited
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Swallow

Swallows are small, agile passerine birds in the family Hirundinidae, known for their long, pointed wings, forked tails and aerial insect-feeding.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 26, 2026|2 min read| Fact-checked

Swallows are small, agile passerine birds in the family Hirundinidae, known for their long, pointed wings, forked tails and aerial insect-feeding. In many English-language contexts, “swallow” commonly refers to the Barn Swallow (Hirundo rustica), a widespread migratory species found across much of the Northern Hemisphere.

Description

Swallows are small birds with slender bodies, long pointed wings and a forked tail. The Barn Swallow is typically dark blue-black above with a reddish throat and pale underparts.

Behaviour and diet

Swallows are highly aerial birds that spend much of their time on the wing. They feed mainly on flying insects such as flies and aphids, which they catch while flying.

Habitat and nesting

They are common in open habitats near water and farmland, and many species adapt well to human buildings. Barn Swallows build mud-and-straw cup nests on ledges, in barns and under eaves.

Migration

Many swallows are long-distance migrants that breed in temperate regions and winter farther south. Barn Swallows breeding in the UK typically move to Africa for the winter.

Conservation

Barn Swallow populations have shown declines in some regions, including North America, while UK trend data show fluctuation and strong regional variation. Conservation status can vary by region and assessment system.

Key facts

  • Swallows are adapted for catching insects in flight.
  • They typically have blue or blue-black upperparts, pale underparts and a deeply forked tail.
  • Barn Swallows often nest on ledges and under the eaves of buildings using mud nests.
  • They are summer visitors in parts of Europe, including the United Kingdom, where they usually arrive in April and leave in October.
  • Swallows are widespread, but the term may refer either to the bird family as a whole or to the Barn Swallow specifically.
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Canadian context

Swallows are familiar summer birds in Canada, where several species breed and hunt insects over fields, wetlands and open water. Their seasonal migrations and insect-eating habits make them relevant to Canadian birdwatching and agricultural landscapes.

Frequently asked questions

What is a swallow bird?
A swallow is a small, agile insect-eating bird in the family Hirundinidae, often seen flying low over open habitats while catching insects in the air.
Does “swallow” mean a specific species?
Often yes: in the UK and Ireland, “swallow” commonly refers to the Barn Swallow (Hirundo rustica), though the word can also mean the broader bird family.
What do swallows eat?
They mainly eat flying insects such as flies and aphids, which they catch while in flight.
Where do swallows nest?
Barn Swallows usually nest on ledges or under the eaves of buildings, especially in barns, farm structures and similar sheltered places.
Are swallows migratory?
Many species are migratory. Barn Swallows breeding in temperate regions typically move south for winter, including to Africa.
Are swallows common in Canada?
Yes. Swallows occur in North America, including Canada, where several species breed and migrate seasonally.

References

  1. RSPB — https://www.rspb.org.uk/birds-and-wildlife/swallow
    Supports: Description, habitat, migration and UK trend notes for swallow/Barn Swallow.
  2. The Wildlife Trusts — https://www.wildlifetrusts.org/wildlife-explorer/birds/swallows-swift-martins-and-nightjar/swallow
    Supports: Scientific name, plumage, nesting, diet, habitat and conservation status in the UK.
  3. Cornell Lab of Ornithology — https://www.allaboutbirds.org/guide/Barn_Swallow/id
    Supports: Identification features including shape, wings and tail.
  4. Cornell Lab of Ornithology — https://www.allaboutbirds.org/guide/Barn_Swallow/lifehistory
    Supports: Population trend, global breeding population estimate and conservation concern score.
  5. U.S. Fish & Wildlife Service — https://www.fws.gov/story/nuisance-swallows
    Supports: Swallow species present in North America.
  6. Woodland Trust — https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/animals/birds/swallow/
    Supports: Habitat, diet, appearance and predation notes.