Northern Prairie Wildlife Research Center
STATUS: Rare or uncommon.
HABITAT: Found in areas with rocky cliffs available for nesting, varying from ocean cliffs to mountain ledges, at elevations from sea level to 11,000 feet.
SPECIAL HABITAT REQUIREMENTS: Crevices or ledges on rocky cliffs for nesting, preferably near or behind a waterfall.
NEST: Nests in small colonies, from 5 to 15 pairs, on a sea cliff, ledge, or cave, or in a crevice or ledge on a sheer, high, moist cliff face near or behind a waterfall, or over a pool.
FOOD: Feeds exclusively on insects captured, usually high in the air, during long-distance foraging flights over all types of terrain. It eats various flies, midges, beetles, termites, flying ants, aphids, bees, wasps, and some spiders.
REFERENCES: Bailey and Niedrach 1965, Lack 1956, Terres 1980, Verner and Boss 1980.