This is the only large Cypseloides swifts known to occur north of Sinaloa, Mexico. In most regions where it occurs it is rather uncommon and local but in its British Columbia breeding range, flocks of several thousands have been seen during the breeding season and during migration.
The largest swift in the U.S. and Canada. Black overall with pale gray head. The tail is forked, though there is some variation in this. When seen in the distance, this swift appears long-winged. In the northern part of its range, it is the only strikingly dark swift with a forked tail.
Distribution and Population Trends
Black Swift has an extensive range but within this range occurs in rather isolated pockets sometimes separated from each other by hundreds of miles. It is found from the Nearctic to Central America and in the West Indies. In North America, its breeding range extends from southeastern Alaska through northwestern and central British Colombia and southwestern Alberta south along the western coastal states to southern California, northwestern Montana, Colorado, central Utah, to north-central New Mexico. Black Swifts nest at Audubon Colorado's Box Canyon Falls and Park Important Bird Area which may support the state's largest population. Audubon California has identified the Fall River Valley Area Important Bird Area within which the state's largest breeding population of Black Swifts (20+ pairs) occurs at McArthur-Burney State Park. The species is thought to winter in South America but the location of its wintering grounds remains a mystery. In general the species never occurs in very high abundance except occasionally flocks of thousands have been seen in its British Columbia range. Though the species is difficult to survey because of its inaccessible nest sites and high-flying habits, Breeding Bird Survey trend analysis shows a 6.3% per year rangewide decline from 1966-2001. Of greatest concern is the fact that some of the greatest declines are in its British Columbia breeding range where it has traditionally occurred in highest abundance.
Black Swift is considered primarily a mountainous species, occurring over a range of highland habitats, particularly over rugged terrain and coastal cliffs. Nests on canyon walls near water and sheltered by overhanging rock or moss, preferably near waterfalls or on sea cliffs. It occasionally occurs in lowlands during migration or in bad weather conditions. It breeds in California from May to September. Autumn migration from northern portions of the breeding range begins as early as late August. The species' wintering grounds are not definitively known. The nests are shallow cups made of moss bound with mud. Lays one to two eggs. Feeds on flying insects.
The general relative inaccessibility of nest sites suggests that threats at these sites are not a major problem though increasing numbers of recreational rock-climbers in some areas and hikers and cave explorers near waterfalls may disturb birds. A more likely broad-scale threat is from decreases in aerial insect abundance from habitat loss and use of pesticides on breeding and wintering grounds. Birds may also be ingesting pesticides directly and bioaccumulating them in tissues which may cause decreases in reproductive output and increases in adult mortality, especially under extreme weather conditions.
While little conservation activity has been directed at the Black Swift, some actions for other species may benefit this one. For example, seasonal closures of cliff areas from recreational rock-climbers to protect Peregrine Falcons and other birds could decrease human activity near potential Black Swift nest sites. On public lands, government agencies should consider similar seasonal closures at known Black Swift nesting sites and rerouting of trails near waterfall breeding areas. Land protection activities in swift foraging areas should help to protect the insect populations necessary for this species' survival.
Unfortunately, the lack of basic knowledge about the species' life history and factors causing population declines currently hampers our ability to take actions that we know will stop the declines and increase swift populations. Research to better understand these issues should be a priority for government and university scientists.
What Can You Do?
Audubon's Important Bird Area program is a vital tool for the conservation of Black Swifts as well as other species. To learn more about the Important Bird Area programs in states with breeding populations of Black Swift, and how you can help, visit: http://www.audubon.org/bird/iba/
Support local land trusts, government agencies, and other organizations working to preserve Black Swift foraging and nesting habitat in your area. Contact your state Important Bird Areas coordinator (http://www.audubon.org/bird/iba/state_coords.html) to find out if there are sites in your area important for Black Swifts that need increased protection.
Volunteers are crucial to the success of programs that monitor the long-term status of wintering populations of Black Swift and other bird species. Audubon's Christmas Bird Count (CBC) is one of the longest-running citizen-science monitoring programs in the world and has helped to follow changes in the numbers and distribution of Black Swift. To learn more about the CBC and how you can participate, visit: http://www.audubon.org/bird/cbc
Information on where Black Swifts occur and in what numbers is vital to conserving the species. Help in monitoring this and other species by reporting your sightings to eBird. A project of Audubon and the Cornell Lab of Ornithology, eBird is the world's first comprehensive on-line bird monitoring program: http://www.audubon.org/bird/ebird/index.html
Chantler, P.1995. Swifts: A Guide to the Swifts and Treeswifts of the World. Yale University Press, New Haven, CT.
Kaufman, K. 1996. Lives of North American Birds. Houghton Mifflin Company, Boston, MA.
Raffaele, H., J. Wiley, O. Garrido, A. Keith, and J. Raffaele. 1998. A Guide to the Birds of the West Indies. Princeton University Press, Princeton, NJ.