An unabridged and unaltered republication of the work first published in 1921 as the Smithsonian Institution National Museum Bulletin 113. The all-inclusiveness of Bent's volumes on North American birds has made them classics of our time. Arthur Cleveland Bent was one of America's outstanding orthinologists, and his twenty-volume series on American birds, published under the auspices of the Smithsonian Institution, forms the most comprehensive, most complete, and most-used single source of information in existence. No ornithologist, conservationist, amateur naturalist or birdwatcher should be without a copy. In this volume the reader will find an encyclopedic collection of information about 50 different gulls and terns. Not a group of general descriptions, but a collection of detailed, specific observations of individual flocks throughout the country, it describes in readable language and copious detail the nesting habits, plumage, egg form, distribution, food behavior, field marks, voice, enemies, winter habits, range, courtship procedures, molting information, and migratory habits of every known North American gull and tern. Completely modern in its approach, the study was made with the full recognition of the difficulties inherent in the observation and interpretation of wild life behavior. For that reason, not only the reports of hundreds of contemporary observers throughout the country were utilized, but also the writings of America's great naturalists of the past - Audobon, Burroughs, William Brewster. The complete textual coverage is supplemented by 16 full- page black-and-white plates showing types of eggs, and 77 plates containing 149 photographs of young at various stages of growth, nesting sites, etc.