Now in its fourth edition, the National Geographic Field Guide to the Birds of North America is the ultimate birder's field guide. Sturdy, portable, and easy-to-use, it features the most complete information available on every bird species known to North America. This revised edition features 250 completely updated range maps, new plumage and species classification information, specially commissioned full-color illustrations, and a superb new index that allows birders in the field to quickly identify a species. The National Geographic Field Guide to the Birds of North America, Fourth Edition will continue to be a bestseller among the fastest-growing sector in the U.S. travel market--the nearly 25 million people who travel each year specifically to observe wild birds.