In the past 40 years, Canadian swift populations have plummeted by 96%

The Chimney Swift Chaetura pelagica is a little, high-flying, dark grey bird whose diet consists entirely of insects caught on the wing. It spends summers in eastern North America and winters in South America. In the 40 years since 1968, Chimney Swift numbers in Canada have declined by 96% (8.3% annually, on average).

In Canada and the United States, theonly two countries where Chimney Swifts nest since the mid-1960s, numbers have been dropping by 1.5% per year. Continentally, numbers have fallen nearly 30% in the last decade. In the spring of 2009, the IUCN (International Unionfor the Conservation of Nature) assigned the status of Near Threatened to the Chimney Swift. While many states report declines, the decrease has been more pronounced in Canada. In the past 40 years, Canadian swift populations have plummeted by 96%. This represents a 8.3% population decrease per year. In Ontario, the average decline rate during the past decade or so stands at a staggering 18.7% annually. Within the whole of the Chimney Swift range, the most acute population declines havebeen found in the northeastern United States and adjacent Canada. This region lies down-wind of or within an area having a high density of human population as well as a huge industrial and environmental footprint. In 2007, researchers suggested there may be as few as 12,000 breeding Chimney Swifts remaining in Canada. Of these, they estimated that about 7,500 reside in Ontario, 2,500 in Quebec, and the remainder in western Canada and the Maritimes.

Source: CHIMNEYS AND CHIMNEYSWIFTS IN LONDON, ONTARIO
By Winifred Wake, Chimney Swift Liaison for Nature London (McIlwraith Field Naturalists) May 19, 2011
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