The second edition (2014) is essentially an entirely new book, created by revising every element of the first edition, adding some new material, and assembling the updated parts into a new whole. Over 100 new species have been added, and over 600 new images. Most of the original paintings have been retouched in some way, and all were rescanned using the latest technology. The text is largely rewritten, maps updated, and the layout adjusted to allow more text and a more logical arrangement of text on each page.
Information from the publisher Alfred A. Knopf, Inc.
The creation of the Sibley Guides
The original (2000) edition of the Sibley Guide to Birds represents more than 12 years of work. The final draft of the artwork and text took over six years to complete, and the finished book was published in October 2000.
Before painting and writing the final draft I spent over 6 years working on the problems of layout and design. The challenge was to meet the goal of illustrating every species and every significant plumage variation; illustrating every species in flight from above and below; describing the complete range of vocalizations for each species; showing all significant subspecies variations; and doing it all in a format that is logical and easy to understand so that even beginners would not be overwhelmed by the amount of information.
The solution was a new and unique design arranging each species in a vertical column on the page. This allows the user to make comparisons easily between different plumages of the same species (by scanning up and down) as well as between similar plumages of different species (by scanning left to right). If you’ve seen a drab fall warbler, all you need to do is scan the upper images of each species to see all of the drabbest warblers. If you’ve seen a woodpecker in flight, a quick horizontal scan across several pages will show all the possibilities at a glance.
More information is available here
Also available from:
First printing – October 2000
First printing – March 2014