Barn Swallow (Hirundo rustica)

Length about 7 inches; distinguished among our swallows by deeply
forked tail. While they breed throughout the United States, they
winter to South America.

This is one of the most familiar farm birds and a great insect
destroyer, seeking prey from daylight to dark on tireless wings. Its
favorite nesting site was barn rafters, upon which it stuck mud
baskets to hold its eggs. But modern barns are fewer and so tightly
constructed that swallows cannot gain entrance, and in much of this
country, they have turned to boat docks, commercial buildings,
summer homes, and the out buildings of rural suburbs to keep the
species going. Like other rural birds, they have to adjust to changing
land-use patterns.