Qualifies for the list as a Declining Yellow List Species

Photo: Bill Schmoker http://schmoker.org

The Black Swift is an uncommon and local breeding species at scattered localities in mountainous regions and coastal cliffs of the western U.S. including southeastern Alaska. It is also found in western Canada, Mexico and Central America, and in the West Indies, where it is resident and relatively common. The migratory populations are presumed to winter in parts of northern and western South America, but the nonbreeding range is not well known.

The five ecological requirements for nesting locations are water, high relief, inaccessibility, unobstructed flyways, and darkness. These represent the consequences of nesting behind or next to waterfalls or in sea caves. Its inaccessible nest sites and rapid flight high in the air mean it is hard to census the species. Continental populations are estimated at 10-15,000 individuals.

There is little information on population trends, though recent declines in its British Columbia breeding range are cause for concern. Pesticide use may be causing a decrease in abundance of aerial insects; in addition the birds may be accumulating pesticides in tissues, resulting in decreased reproduction and adult mortality. Managers of public lands should assure that nesting sites are not disturbed by hikers and rock climbers during the breeding season.