Tree Swallow: Medium-sized swallow with iridescent blue-green upperparts and white underparts. The wings are dark gray and tail is dark and forked. Black bill, legs and feet. Swift, graceful flight, alternates slow, deep wing beats with short or long glides. Turns back sharply on insects it passes.
Range and Habitat
Tree Swallow: Breeds from Alaska east through southern Nunavut to Newfoundland and south to California, northern Arizona, Texas, and Georgia. Spends winters in California, Mexico, and along the Gulf Coast and Mid-Atlantic states. Preferred habitats include open areas near water, such as fields, marshes, meadows, shorelines, beaver ponds, and wooded swamps with standing dead trees.
The swallows are one of the one hundred eighteen families of birds in the order PASSERIFORMES (pronounced pas-ser-i-FOR-meez); a large taxonomic order that includes waxwings, tanagers, finches, and swallows.
A family distributed almost everywhere, the Hirundinidae (pronounced hir-un-DIN-uh-dee) are composed of eighty-eight species of swallows in nineteen genera.
There are twenty-two species of swallows in North America in nine genera. North American swallow species include the well known Barn Swallow, the Cave Swallow, and the Purple Martin.
The swallows are best known for their graceful, swooping flight and for nesting in barns, under bridges, and in an on other human-made structures. The Purple Martins of eastern North America are well known for colonial nesting in “martin houses” put up for this purpose.
The long, pointed wings and streamlined bodies of swallows are adaptations for their aerial lifestyle. These small birds have medium length to long tails that can be squared or forked in shape. Their bills are short with wide gapes, and their legs short with small feet.
Swallows come in variety of colors, the juveniles of most species and females of Progne genus martins with duller plumage in general. Depending on the species, adults have iridescent plumages in shades of green, blue, violet, and deep purple, while others are plain brown in coloration. Reddish orange plumage occurs on the underparts, throats and heads of some species, others have snow white underparts, and the Cliff and Cave Swallows have white streaks on their backs.
This family is found throughout North America except for the most northern of tundra habitats. Swallows utilize a wide variety of non-forest habitats, but are most common around rivers, lakes, and other wetlands that provide abundant food in the form of flying insects and nesting sites in the form of bridges, riverbanks, and dead snags.
Most swallow species are long distance migrants to Central and South America.
Swallows are very social birds, many species nesting in colonies and foraging in flocks. They nest in holes in the banks of rivers and lakes, in dead snags, and also build mud nests in caves, cliffs, and on structures such as bridges, barns and buildings. Foraging for flying insects and other arthropods is done in the air with fast, graceful, swooping flight.
In North America, no swallow species are threatened. This might be related to their preference for open, non-forest habitats, and their ability to nest on human-built structures.
Some populations of the Purple Martin became adapted to breeding in gourds set out by Native Americans before Europeans arrived. Eventually, they became so used to breeding in structures set up by people that in eastern North America they no longer use natural cavities. Natural cavities are mostly used by populations in western North America, however, which might explain why they are much more local in occurrence in that region.