These widely anticipated volumes comprehensively treat the nearly 1600 species of birds that can be found in mainland Ecuador. The authors describe Ecuador this way: "One of the wonders of the natural world. Nowhere else is such incredible avian diversity crammed into such a small country. Birds are, happily, numerous in many parts of Ecuador: even the downtown parks of the big cities such as Quito and Guayaquil host their complement." Volume II, Field Guide, contains 96 full-color plates and facing pages of descriptive text, a color map of Ecuador, 2 line drawings of bird anatomy, 115 silhouette outlines, and nearly 1600 distribution maps. All species are illustrated in full color, including migrants and vagrants and visually distinctive subspecies. The text focuses on the field identification aspects of each species, including their behavior, vocalizations, and nest appearance.