Every June hundreds of Canadians and Americans volunteer to participate in the Breeding Bird Survey, helping to track trends in bird populations. Four decades of these counts show that the birds that are declining the most rapidly in North America are the prairie birds at the heart of the continent — the birds that need grassland. Forty years of data is enough to prove that grassland bird decline is for real — not merely cyclical or temporary. Yet it doesn’t give much in the way of historic background. How many Sprague’s Pipits were there 60 years ago? What did the prairie sound like before it was settled, or even shortly after settlement?
For more from this story: http://www.cbc.ca/ideas/features/pastures-unsung/index.html
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