The changing climate threatens hundreds of species of birds, and may put half of all North American birds at risk of extinction by the end of the century. That's the conclusion of a seven-year study released today by the National Audubon Society. The study looked at more than 40 years of climate data and bird census numbers. For more on the implications closer to home, Tom Porter talks with Doug Hitchcox, a naturalist with Maine Audubon.
View the National Audubon Society report.