Canary in the coal mine – finch

When it comes to global warming, the canary in the coal mine isn’t a canary at all. It’s a purple finch.

An Audubon Society study released Tuesday found that more than half of 305 birds species in North America, a hodgepodge that includes robins, gulls, chickadees and owls, are spending the winter about 35 miles farther north than they did 40 years ago.
NBC News, 10 Feb 2009