The Barn Swallow is the most abundant and widely distributed swallow species in the world.
Female Barn Swallows prefer to mate with males that have the longest and most symmetrical tails.
An unmated male Barn Swallow may kill the nestlings of a nesting pair. His actions often succeed in breaking up the pair and afford him the opportunity to mate with the female.
For more information about Barn Swallows, visit these sites: