This is a handy, pocket-sized foldout reference to the 45 most commonly seen North American warblers. • Photos include side-on, underside, and 45-degree views • Drawings of undertail patterns provide at-a-glance comparisons between species • Icons depict generalized color patterns for each bird and where the species is usually found—on the ground, low in trees or vegetation, midstory, or toward the top of trees • Succinct text describes key identification features for each species • A QR code takes you to a range of common vocalizations for each species About the authors: Scott Whittle and Tom Stephenson are the authors of the award-winning book and companion app The Warbler Guide and The Warbler Guide App (both Princeton).