Banks 1959 Stelgidopteryx May 10 month, San Mile Creek, sea level, Mendocino C. Calif. There are several of these birds here, feeding with Cliff & Barn Swallows, and exp. flying around a bluff on the county road going into the Foster place. Cannot tell if they are nesting - they do not enter holes in the cliff, but fly by less much more often than the other species. The county road crew, however, is eating away the cliff, so the habitat may be ruined.