Birds of North America Trial
Birds of North America Online
http://bna.birds.cornell.edu/BNA/
Birds of North America Online (BNA Online) is a continually updated, comprehensive reference for life history information on over 700 different bird species that breed in the United States and Canada. In addition to the text, figures, and illustrations included in the original hard copy version, BNA Online includes photo galleries, vocalizations, updated text and video for many species. This reference resource is maintained by the Cornell Lab of Ornithology.
Available until May 10, 2007