The Encyclopedia Americana (1920)/Cliff Swallow

CLIFF SWALLOW, a swallow of North America also known as the eaves swallow, which makes its nest about barns and outbuildings. It has a white forehead, a gray breast and collar and a square tail. Its nest is always placed on the outside of the building, unlike that of the fork-tailed barn swallow. Before the country was settled these birds nested in colonies on the sides of cliffs. Its nests in these situations were globular with a narrow neck. With the advent of civilization the birds abandoned the cliffs and began to build their nests in the better-sheltered spaces under the eaves of houses and bams. Their nests have also in some cases lost their flask-like form, now being mostly in the shape of a cup. Consult Knowlton, ‘Birds of the World’ (New York 1909).