Taking its place as one of the most common and widespread bird species in the U.S., the Cliff Swallow is an incredible swallow species that naturally builds nests out of wet mud on the ledges of cliffs, and have taken advantage of man-made structures.

William L. Dawson, a famous ornithologist of the early 1900s and author of “Birds of California,” is quoted as saying,“Doubtless the Lord must love the Cliff Swallows, else he would not have made so many of them.”

Cliff Swallows will nest in colonies of up to 6,000 nests, and have a breeding range from Panama all the way north to Alaska, according to Birds of the World.

Originally, these birds did not nest east of the Great Plains, however, that changed when habitats were made for them to build their nests on in the form of culverts, bridges and the eaves of buildings. 

Cliff Swallows first arrive in Washington in April, after which they become common throughout the whole state as they establish and breed through the following month, according to BirdWeb. During their non-breeding season, these birds spend their time in tropical South America, mostly wintering through Ecuador, Peru, Bolivia and Brazil.