The definitive photographic guide to North American gullsGull identification can be challenging for even the most seasoned birder. While these birds are common to coasts, lakes, and rivers, they exhibit remarkable plumage changes related to age, which is sometimes complicated by similarities between species and a readiness to hybridize. This book provides an invaluable identification guide to all regularly occurring gull species and subspecies throughout North America. It is packed with the very latest research on field identification, updated taxonomy, current distribution trends, color maps, and helpful notes on natural history, aging, and molt. The Gull Guide integrates the essential elements that are critical to understanding gulls, setting an entirely new standard for identifying and enjoying these marvelous birds. Features more than 1,800 superb color photosCovers 36 gull species as well as 7 of the most commonly encountered hybrid gullsGives equal attention to rarities from Asia, Europe, and South AmericaDescribes the key characteristics of all age groups, from juvenile through adult plumagesInnovative photo collages give side-by-side comparisons, enabling readers to distinguish between similar species and avoid common pitfalls associated with gull identificationComes with a one-of-a-kind “cheat sheet” describing key features of select Larus speciesA must for the bookshelf of every birder and ornithologist