Birders who come to the American Southwest often keep an eye out for Mexican species that stray across the border. Many neotropical migrants of western North America winter in Sonora, and a host of hummingbirds make their home south of the border as well. This eagerly awaited volume by two respected authorities covers more than 500 species of birds and contains a vast amount of information not available elsewhere. The Birds of Sonora describes all the species known from that state and includes information on distribution, seasonal patterns of occurrence, abundance, and habitats. The first book of its kind in more than half a century to treat birds of this Mexican state immediately south of Arizona, it also contains details of nesting activity for breeding species, provides insight into factors influencing distribution, and notes historical changes in status. Each account is accompanied by a range map depicting the bird's range in Sonora—valuable information not available from any other source and useful to anyone interested in the distribution and ecology of North American birds. Drawings by internationally known wildlife artist Ray Harm enhance many of the entries. Because other books on Mexican birds don't treat Sonora in detail, The Birds of Sonora is an indispensable resource for birders, and its background descriptions of Sonoran geography, climate, and habitats also make it a key reference for conservation and land use planning. A useful companion to field guides, it is a narrative account that puts readers in touch with birds of this important biogeographic area.