Audubon scientists (click here) have used hundreds of thousands of citizen-science observations and sophisticated climate models to predict how birds in the U.S. and Canada will react to climate change. Our work defines the climate conditions birds need to survive, then maps where those conditions will be found in the future as the Earth’s climate responds to increased greenhouse gases.
It’s the broadest and most detailed study of its kind, and it’s the closest thing we have to a field guide to the future of North American birds.
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That is $20 billion in the USA alone. Birding encompasses a global community and migratory birds are important.