While the Sibley Guide to Birds (reviewed here) may be the ultimate field guide, the National Geographic Complete Birds of North America is the desk reference to go with it. First, this is not a field guide by any stretch of the imagination. It’s larger and heavier than the Sibley’s guide as well as being a hardcover book and not a paperback.
Physically the National Geographic Complete Birds of North America is a well bound hard cover book. My copy came with a printed dust cover featuring a portrait of a Golden Eagle, that mirrors exactly the printing on the hard cover it’s self. The pages are a medium weight coated paper with a matte finish. The printing is clear and readable and the illustrations are usually well reproduced. Though the same complaint I have with the Sibley books I have here which is that sometimes the illustrations are a bit too small to make out all the detail I’d like to be able to see.
The book is setup similar to the Sibley guides, there’s a short–in this case 4-page–introduction covering the basics of bird nomenclature, spotting marks, as well as some information about the diagrams used in the book. From there it immediately goes into the species specific details. This is where the National Geographic Complete Birds of North America separates itself from the Sibley guides and makes it clear it’s a reference not a field guide.
While the Sibley guides are intended for field use with their heavy focus on providing as many illustrations as possible laid out in a fashion that’s easy to search though and only short textual descriptions and notes. The National Geographic Complete Birds of North America is much more verbose, and that’s a good thing. This is what I think is the key to what makes the National Geographic Complete Birds of North America a solid desk reference. There is not only an illustration of the species but also a full textual description of the same along with some information about behavior. I find this immensely helpful, as under many conditions it can be difficult to tell if something is colored buff or light gray, but the text clears that up with out question.
There are some differences in the organization of this book from the Sibley book, though they are very close. I have prepared a PDF showing the differences. In addition, the National Geographic Complete Birds of North America is slightly more comprehensive featuring several species that are not contained in the Sibley guide.
I find that both guides are valuable references. Actually the National Geographic Complete Birds of North America, is the middle of my 3 book bird reference set. The Sibley Guide to Birds is my first reference, but when I either cannot find a bird or am not completely sure of an identification, I turn the the National Geographic Complete Birds of North America. The final book is the Sibley Guide to Bird Life and Behavior (review coming) which is where I turn when I need more information about the behaviors of a species I’m trying to photograph.
I strongly recommend both books, but if your budget is tight and you can only afford one I lean towards the Sibley Guide to North American Birds or one of the two region specific Sibley guide books first and save this one for later.