I now can identify certain birds by song thanks to this book. The Backyard Birdsong Guide: A Guide to Listening by Donald Kroodsma is a real treat — especially as Spring approaches. Look up a variety of birds located in Eastern and Central North America and you will find a photo of the bird, a brief description, information about their habitat, as well as information about their singing. But what is really nifty is that you can then punch in the number located next to the bird in the sound device located in the book and listen to the bird singing!