<P> The barn swallow (Hirundo rustica) is the most widespread species of swallow in the world . It is a distinctive passerine bird with blue upperparts, a long, deeply forked tail and curved, pointed wings . It is found in Europe, Asia, Africa and the Americas . In Anglophone Europe it is just called the swallow; in Northern Europe it is the only common species called a "swallow" rather than a "martin". </P> <P> There are six subspecies of barn swallow, which breed across the Northern Hemisphere . Four are strongly migratory, and their wintering grounds cover much of the Southern Hemisphere as far south as central Argentina, the Cape Province of South Africa, and northern Australia . Its huge range means that the barn swallow is not endangered, although there may be local population declines due to specific threats . </P> <P> The barn swallow is a bird of open country that normally uses man - made structures to breed and consequently has spread with human expansion . It builds a cup nest from mud pellets in barns or similar structures and feeds on insects caught in flight . This species lives in close association with humans, and its insect - eating habits mean that it is tolerated by humans; this acceptance was reinforced in the past by superstitions regarding the bird and its nest . There are frequent cultural references to the barn swallow in literary and religious works due to both its living in close proximity to humans and its annual migration . The barn swallow is the national bird of Estonia . </P> <Table> <Tr> <Td> </Td> <Td> Recording of barn swallows A barn swallow song recorded at the Minnesota Valley National Wildlife Refuge </Td> </Tr> <Tr> <Td_colspan="2"> Problems playing this file? See media help . </Td> </Tr> </Table>

Where do barn swallows go in the winter