The Sibley Guide to Birds, Second Edition: A Review of an Iconic Guide in a New Edition
10,000 Birds
APRIL 1, 2014
In The Warbler Guide , Tom Stephenson and Scott Whittle drew on science to create sonograms, visual depictions of bird song that showed just how a Pine Warbler trill really was different from a Chipping Sparrow trill. In a huge improvement, Sibley Two includes page references for each species (see Falcons introductory page above).
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