Cliff Swallows nest in colonies of hundreds or even thousands — the famous 'swallows of Capistrano' are this species.
They build gourd-shaped enclosed mud nests with a small entry tunnel, distinct from the open-cup nests of Barn Swallows.
Like Barn Swallows, they readily switched from cliffs to bridges, culverts, and building eaves and now thrive across human landscapes.
Cliff Swallows nest colonially under bridges and barn eaves. A single homeowner can rarely 'attract' a new colony, but you can support an existing one.
If a colony has formed under your eaves, the open shelf can host overflow pairs. Mount 10–15 ft up against a vertical wall.
Mud is essential — a small puddle or mud patch nearby is critical during nest-building.
Aerial insects. No feeders work.
House Sparrows take over Cliff Swallow nests aggressively; managing sparrows is the most effective protection.
Don't power-wash old nests off — colonies will use them again the next spring with minor repair.
A colonial swallow that breeds across most of North America and winters in South America. Highly tied to vertical surfaces — historically cliffs, now mostly man-made.
Common throughout the Pacific Coast, Mountain West, and Great Plains.
Local but increasing east of the Mississippi; abundant around bridges and barns.
Winters in southern Brazil, Paraguay, Argentina, and Uruguay.
Open country near vertical surfaces — cliff faces in the West, bridges, culverts, and barn eaves elsewhere. Mud puddles are essential within ¼ mile.
No entrance hole, no front wall — just a sheltered ledge. Includes drainage and the integrated mounting tab.
See the full lineupLong-distance migrant from southern South America. Mud-source proximity is the single biggest factor in nest-building success.