This swallow averages 13.5 cm (5 inches) long and weighs about 20 g. The bill is tiny. The adult Tree Swallow has iridescent blue-green upperparts, white underparts, and a very slightly forked tail. The female usually has duller colours than the male, often more greenish than the more bluish male. The juvenile plumage is dull grey-brown above and may have hint of a gray breast band.
Habitat and Distribution
The Tree Swallow is a migratory bird that breeds in North America and winters in Mexico, Central America and the Caribbean. It is a very rare vagrant to Western Europe.
They are excellent fliers and take off from their perch and acrobatically catch insects in their bills in mid-air. The diet consists of mainly insects, supplemented with fruit.
Tree Swallows nest in natural or artificial cavities near water and are often found in large flocks. They readily use nest boxes, including those built for bluebirds. The nest The nest consists of multiple layers of grasses and thin twigs, and is often lined with feathers from other species. The female lays 4 to 7 white eggs and incubates them by herself. The eggs hatch in about 14 days. Fledging is from 16 to 24 days.
Calls and Songs
Their song is an extended series of variable chirping notes to Chrit, pleet, euree, cheet, chrit, pleet.