A Photographic Guide to North American Raptors.—Brian K. Wheeler and William S. Clark. 1999. Academic Press, San Diego, California. xviii + 198 pp., 377 color photographs. ISBN 0-12-745531-0. Paper, $19.95.—Field guides are to field ornithologists what hammers are to carpenters: essential tools of the trade. With the right field guide in hand, even a novice field worker in a new land stands a sporting chance of identifying birds. Without a good field guide, frustration can quickly set in. The role that field guides (together with their essential companion, binoculars) have played in ornithology is difficult to overstate. Consider for example, our understanding of the migratory behavior of Broad-winged Hawks (Buteo platypterus). At the beginning of the twentieth century, this obligate transequatorial migrant was thought by many to be a resident species throughout much of its North American breeding range. The broadwing was, after all, cryptic and difficult to see during the breeding season. The paucity of winter broadwing sightings, confounded by their frequent misidentification as young Red-shouldered Hawks (B. lineatus), led even seasoned field workers to consider the broadwing a year-round inhabitant in many areas.
All of that changed, however, as prismatic binoculars came into widespread use among field workers, leading to the development of the modern field guide. Roger Tory Peterson's A Field Guide to the Birds (1934) and its successors, as well as other regional bird guides revolutionized field identification of birds. But, over the years, that was refined to the point where the guides themselves demanded the creation of a new kind of bird guide devoted to specific birds within a particular region.
For raptors, these new specialty guides have run the gamut from “gestalt” text driven—black-and-white illustrated offerings like Harkness and Murdoch's Birds of Prey in the Field (Witherby Press, London, 1971) and Dunne, Sibley and Sutton's Hawks in Flight: The Flight Identification of North American Migrant Raptors (Houghton Mifflin, Boston, 1988)—through Clark and Wheeler's traditional full-color, art-driven A Field Guide to Hawks in North America (Houghton Mifflin, Boston, 1987) to, finally, the color-photograph-filled volume reviewed here.
Kimball L. Garrett's excellent review of the 1995 edition of Wheeler and Clark appeared in The Auk in 1997 (Auk 114:306–307). I won't go over previously trodden ground here as the current edition remains almost identical to the earlier hardcover edition except for a new cover, some minor corrections in typesetting, some photo reorientation, and several additions to the text that focus principally on age differences in eye color. I will, instead, reflect on my experiences using the earlier version and introducing it to others while working at a raptor migration observation site in eastern Pennsylvania in the United States.
Anyone who has spent time in the field helping others identify raptors knows that the new observers will need all the help they can get. Although raptors are relatively large birds, under many circumstances they can be difficult, often impossible, to identify to species level. Although part of the difficulty arises from the fleeting glimpses we often have of the birds, much of the problem can be traced to subtle intraspecific variation in their appearance. In many instances, plumage variation within a species can be greater than between species, making identification quite difficult at times. Wheeler and Clark deal with those circumstances by presenting 377 color photographs of North American raptors and vagrants, as compared to 33 and 193 images, respectively, in the first (1934) Peterson bird guide and the most recent National Geographic Field Guide to the Birds of North America (National Geographic Society, Washington, D.C., 1999). In most instances, the photos in Wheeler and Clark's guide are crisp, clear, and helpful. Nuances in species-specific coloration and individual variation within species, including those related to age and sex, are further detailed in the relatively sparse text and highlighted in the volume's copious photo legends. The book also provides an exhaustive (sometimes a bit exhausting) review of the general complexities of raptor identification.
Does the book succeed in its avowed mission? Most certainly, but only when used in conjunction with other guides. Although I would not recommend Wheeler and Clark's volume as a first and only guide for most hawk watchers, I would recommend it as a supplement to other specialty raptor guides. In conjunction with a more comprehensive bird guide, the book can turn an otherwise frustrating day at a raptor migration observation site into a rewarding experience for teacher and pupil alike. The work can also serve as a great teaching tool away from the field. In summary, I highly recommend this useful guide amazingly priced at $10.00 less than its 1995 edition!