five million mature individuals, though the population is believed to be decreasing. No immediate threats have been identified. "Populations are not known to be affected by humans." References Further reading Fjeldsa, J. and Krabbe, N. (1990) Birds of the high Andes: a Manual to the Birds of the Temperate Zone of the Andes and Patagonia, South America. Apollo Books, Copenhagen, Denmark Chantler and Driessens, Swifts Stiles and Skutch, A Guide to the Birds of Costa Rica white-collared swift Birds of Central America Birds of Hispaniola Birds of the Dominican Republic Birds of Haiti Birds of South America white-collared swift