Chaetura pelagica

May constitute a superspecies with C. vauxi and C. chapmani (AOU 1998).

Numbers are still in millions.

BREEDING: east-central Saskatchewan east across southern Canada to Nova Scotia and probably Newfoundland, south to eastern New Mexico, southern Texas, Gulf Coast, and southern Florida, and west to southeastern Wyoming and eastern Colorado (AOU 1998). NON-BREEDING: western Peru, northern Chile, and upper Amazon basin of eastern Peru and Brazil (Stiles and Skutch 1989, AOU 1998). MIGRATION: eastern Mexico, Caribbean slope of Middle America, Colombia, and western Venezuela (AOU 1998).

This species is represented by a large number of occurrences (subpopulations), with an estimiated global population of almost 8 million birds (Partners in Flight, 2013).

The most significant threat to the species appears to be the decreasing number of nesting and roosting sites caused by logging operations, the demolition of old abandoned buildings and, especially, the sharp decline in the number of suitable and accessible traditional chimneys, which are this species's main breeding habitat (COSEWIC 2007, R. Windingstad in litt. 2010). It is projected that very few suitable sites will remain within the next thirty years (COSEWIC 2007). The number of breeding sites in Quebec is limited, and it is estimated that only 60% of breeding-age adults actually reproduce; a trend which is thought to be replicated across Canada (COSEWIC 2007). Hurricanes during the migration period and harsh weather conditions during breeding season have caused a considerable number of deaths (COSEWIC 2007, Dionne et al. 2008). In its South American wintering area, the species is threatened by intensive logging operations and by fires (COSEWIC 2007) (Birdlife International, 2014). HABITAT CHANGE: In Texas, construction of homes without fireplaces and the screening of chimneys is thought to have slowed the expansion of the swift within the state (Oberholser 1974). Chimney screening and demolition of buildings (businesses, homes, silos) historically used for nesting/roosting can eliminate important habitat. The loss of historic roosts used by 1000s of individuals during fall migration could be devastating if alternate sites are unavailable. The surface of metal flue pipe emplaced within newly-constructed chimneys is too smooth for swifts to cling to, resulting in the entrapment and death of birds. PREDATION: Confirmed predators of adults include Mississippi Kites (ICTINIA MISSISSIPPIENSIS; Bolen and Flores 1993) and Sharp-shinned Hawks (ACCIPITER STRIATUS; Bent 1940); nestlings are preyed upon by Rat Snakes (ELAPHE OBSOLETA; Cink 1990). OTHER: Large flocks roosting in chimneys are sometimes accidentally killed. Between 3000 and 5000 swifts were killed in October in a chimney in Quincy, Illinois when the heat was turned on due to unseasonably cold weather (Bent 1940). Prolonged periods of wet, cold weather during the spring, which decrease flying insect abundance, can result in starvation (Bent 1940). Birds sometimes also starve during migration (Spendelow 1985). Threats on the wintering grounds are unknown.