Birdwatching Ears

I got the audio companion to Peterson's Field Guide today. In fact there are a couple of audio companions; one is supposed to give you the audio equivalent of the field marks that the field guide gives while the other is supposed to give the various bird songs to help a person learn what to listen for. I'm going to try to listen to it and see if I can start to pick up the sound of birds. If nothing else my latest mania for bird watching should help me to sharpen up my powers of observation anyway.