BRIAN SULLIVAN has conducted fieldwork on birds throughout North America for the past twenty-five years. Birding travels, photography, and field projects have taken him to Central and South America, Australia, Antarctica, the Arctic, and across North America. He has written and consulted on various books, including popular and scientific literature on North American birds. He is a coauthor of several books, and co-creator of the groundbreaking Raptor ID app for mobile devices. He is currently project leader for eBird and photographic editor for the Birds of North America Online at the Cornell Laboratory of Ornithology.