Hirundinidae

Hirundinidae, commonly known as swallows, is a family of small to medium-sized passerine birds celebrated for their aerial lifestyle and insectivorous feeding. Members have slender bodies, long pointed wings, and a short to moderately forked tail. They are highly agile fliers, catching insects on the wing with quick, often acrobatic movements.

Swallows are distributed worldwide, occupying a wide range of open habitats near water, fields, savannas, and human settlements. They frequently nest on vertical structures such as cliffs, bridges, eaves, and buildings. The family includes several genera, notably Hirundo (true swallows), Delichon (house martins), Progne (martins), Petrochelidon (cliff martins), Tachycineta, and Stelgidopteryx, among others. They are typically migratory, with many northern species wintering in warmer regions, though some populations are resident in tropical areas.

Diet consists almost entirely of flying insects, which they seize in rapid, sustained flight. Vocalizations are varied, and many species form large, noisy colonies during the breeding season. Nesting commonly involves mud to build cup- or vase-shaped structures attached to suitable vertical substrates; sites are often reused across years, and colonies can be conspicuous.

Reproduction generally includes clutch sizes of several eggs with incubation and fledging shared between the parents. Population trends in swallows are influenced by habitat changes, pesticide use, and availability of suitable nesting sites and aerial prey. Conservation measures often focus on preserving mud sources, reducing pesticide impacts, and providing artificial nest sites.