A huge proportion of Canada’s bird species are in serious decline. Overall, there’s been a 12 per cent drop in bird populations since 1970, says the 36-page report, entitled The State of Canada’s Birds 2012. Forty-four per cent of Canada’s 460-plus species have fallen in number, 66 of them so dramatically they are considered endangered. At the top of the list of most endangered birds is the spotted owl Strix occidentalis, whose numbers have dropped to a mere “handful”, and the great sage grouse Centrocercus urophasianus, with fewer than 100 males, down from thousands 20 years ago. Populations of grassland birds, such as meadowlarks and bobolinks Dolichonyx oryzivorus, have fallen by 45 per cent since 1970; some species that thrive in the long grasses of the Prairies or the farms of Eastern Canada are vulnerable, with numbers that have dropped by 90 per cent. Birds known as aerial insectivores — basically such species as barn swallows Hirundo rustica, chimney swifts Chaetura pelagica and flycatchers that snatch insects on the wing — are still relatively common, but have seen an overall descent in numbers of 64 per cent.
Source: The Spec.com, June 27, 2012
http://www.thespec.com/news/canada/article/750640--from-spotted-owl-to-…
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