Slightly larger than Barn Swallows, Red-rumps have a lazier, more floaty flight. They arrive well after their cousins and leave later with the nesting site not so reliant upon Man's proximity, though they do use man-made structures such as bridges and drainage culverts, to the roofs of which they stick their closed, tunnel-entrance mud nest.
They mate inside their nest with the tunnel entrance preventing an excess of males during mating.
Despite their beautiful appearance they can be aggressive towards other birds and quite often appropriate Barn Swallow nests if they so wish - if there are recently hatched chicks in any such nest these are summarily ejected to die on the ground.
With a pale, faintly streaked breast, a rufous nape and a pale rump with rusty tinge, it is difficult to mistake them for a Barn Swallow, but the best diagnostic difference is the absence of a dark chin-strap. The rump becomes redder with age. Their flight diagnostic is agreater prevalence for gliding than Barn Swallows.
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