The Sibley Guide to Bird Life and Behavior, published in October 2001, was conceived as the companion to the Guide to Birds. This book provides a wealth of detail about the nesting, mating, and other behavior. Even though these things do not have direct application to identification, and are not included in the identification guide, these behaviors are truly fascinating, and birders enjoy knowing about them. The plan for this book was to provide a layperson's introduction to the most intriguing and interesting facets of the birds' lives - emphasizing things that birders are likely to see and ask about, and things that add to a larger picture of the natural world. Content and images originally posted by Gaga