A Complete Guide to Field Marks of All Species Found in North America West of the 100th Meridian and North of Mexico. "The Birder"s Bible" for more than 60 years, Roger Tory Peterson"s classic Field Guide to Western Birds includes all species found in North America west of the 100th meridian and north of Mexico. Featuring the unique Peterson Identification System, Western Birds contains 165 full-color paintings that show more than 1,000 birds from 700 species. Summer and winter ranges, breeding grounds, and other special range data are shown on easy-to-read range maps.