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 I, Status, Distribution, and Taxonomy, contains detailed information on the ecology, status, and distribution of all species. Introductory chapters deal with geography, climate, and vegetation; bird migration in Ecuador; Ecuadorian ornithology; endemic bird areas in Ecuador; and conservation. Individual species accounts treat habitat, distribution, and taxonomy.