The Crossley ID Guide
Copyright 2011 by Richard Crossley
Published by Princeton University Press
Richard Crossley, an avid birder residing in one of North America's hottest birding spots- Cape May, NJ- breaks new ground with the release of his beyond-comprehensive 529-page tome for identifying eastern birds. (The 'East' is comprised of the Rocky Mountains to the west, Mexico and The Bahamas to the south, Nuussuaq, Greenland to the east, and north of the Arctic Circle up to Boothia Peninsula. Western birds that are known to be eastern vagrants are also included.)
Crossley himself took over 10,000 photographs for this undertaking, and uses them in a myriad of ways. The book starts with a size guide for the various classifications of birds- swimming waterbirds, walking waterbirds, raptors, etc.- which places a picture of each bird to scale with their alpha code and page number on which the particular species is discussed in further detail. The 660 species in the book are illustrated by placing a number of photographs of each species atop a photographic scene akin to its natural habitat as a background. Eastern birders will easily recognize some of the background photographs and be able to verify that the birds are indeed pictured at their usual haunts: the 2nd Street Jetty in Cape May for the Black Skimmer; the area off the 8th Street Jetty in Avalon, NJ for the Black Scoter; or, the Cape May Point, NJ breeding grounds for the American Oystercatcher.
There's not just one photograph for each species, however. Crossley includes photos of juveniles and adults of both sexes, also providing examples of birds as they transition from breeding to high breeding plumage. Any differences in appearance related to age are also accounted for photographically. Nowhere is this more impressive than in the scenes featuring the various species of gulls, which even experts are sometimes unable to identify definitively, occasionally relying on probabilities to make a final determination. There are eight identifying photographs for the Lesser Black-backed Gull alone, documenting yearly changes until the bird finally reaches adulthood. There is also a written description, scientific name, and territorial map for each species of bird.
When one considers the amount of time and effort that Crossley must have placed into developing this guide- especially photographing the birds in flight, which can be quite challenging- the Guide is a relative steal at $35.00. A visual masterpiece, I'd recommend it to any birder of any level of experience.