Amazon.com (ISBN 0679428518, Turtleback)

A favorite of birdwatchers (especially those who prefer photographs to illustrations), this field guide, revised for 2000, accounts for the 544 bird species that live in the region west of the Great Plains. The clearly printed color photographs capture birds at rest and in flight; preceded by black-and-white silhouettes, the plates are organized by visually based, intuitive categories--"hawk-like birds," "pigeon-like birds," and "perching birds," for example--that make on-the-fly identification a fairly simple matter. The images are matched by clearly written text that describes a given bird, gives an approximation of its voice, and details its habitat, range, nests, and behavior. Sized to fit in a jacket or backpack pocket, this is a valuable companion for any birding outing in the region. --Gregory McNamee