The barn swallow is a type of bird that is widespread throughout the world. It can found be in almost all parts of the continental United States and much of Canada. The barn swallow is known for using man-made landscape features and buildings, especially barns, as nesting sites. In North America, it can be identified by the long fork in its tail. No other species of swallow is as widespread or appears in greater numbers.
The adult male barn swallow can be identified by its dark blue head and blue feathers at the front or top of the wings and tail. The longer wing and tail feathers are black. It has a reddish forehead and throat and lighter underparts also tinged with red. The female has lighter coloring, may have whiter underparts, and has a narrower fork in its tail. Immature barn swallows are less deeply colored at the head and over the back.
In the absence of man-made structures, barn swallows naturally nest in rocky shelters like caves or cliffs. Today they are commonly seen nesting in barns and often bridges, culverts, and other human structures near water. Like other swallows, they are known as graceful fliers. In flight, the tail feathers spread wide, and their wingtips appear very pointed. They are also noted for flying low to the ground as the birds search for insects to eat in flight.
The barn swallow migrates annually. In the United States, it begins to return from migration in February in the warmest areas and reaches northern locations in May. By August and September, the birds have usually begun to leave or have already left more northern regions. It usually spends winters in South America, reaching countries as far south as Chile and Argentina.
The male and female share the task of making a bowl-like nest formed of dried mud, which they line with grass. Barn rafters are a common nesting site. After building the nest, the female usually lays between three and seven eggs. Barn swallow pairs are usually monogamous, although this is not always true for the male. Some breeding pairs return to the same nesting site and may even rebuild an old nest in the next year.
Barn swallows can be confused with other species of swallow. One distinguishing feature is the length of the forked tail, which in males may also have whitish markings. They are also followed by their annual arrivals and departures, which occur later in both spring and fall than those of other swallows.
