Cliff Swallow

1/160s at f5.6, ISO:1600, Canon EOS-1D X w/800mm

American Cliff Swallows breed in large colonies. They build conical mud nests and lay 3 to 6 eggs. The natural nest sites are on cliffs, preferably beneath overhangs, but as with the Eurasian House Martin, man-made structures are now the principal locations for breeding. Female American Cliff Swallows are known to lay eggs in and move previously laid eggs into the nests of other birds within the colony. This species has always been plentiful in the west of North America, where there are many natural sites, but the abundance in the east has varied. European settlement provided many new nest sites on buildings, but the population declined in the late nineteenth and early twentieth centuries as the supply of unpainted barns declined. There has been a subsequent revival as dams and bridges have provided suitable sites. It breeds in North America and is migratory, wintering in western South America from Venezuela southwards to northeast Argentina.
Chandler, AZ