Around the early 1950s, during the intermissions of the Sunday radio broadcasts of the New York Philharmonic Orchestra, the announcer introduced recordings of extremely complicated birdcalls. The sounds were obviously somewhat comparable to various musical instruments and marvelously complex. Perhaps one of your bird librarians might be interested in finding the source of the early recordings used in those broadcasts. Also, I have been teaching my local mockingbirds the “birdie, birdie” call of the eastern cardinal, followed by the two-note bridge of “Somewhere over the Rainbow.” They do quite well in repeating them back to me and in teaching them to their offspring.

Dolan Eargle
San Francisco, Calif.