@aallan & @jameswilson -- You two make me wonder what if we combined the tracing paper activity with this idea of drawing a composite bird? I'm imagining picking a certain kind of bird and adding to it every time we see a new one at the feeder -- adding new sheets of tracing paper as necessary. I may give it a try.
p/s. I agree w/Abbi about your cardinal from memory, James. Reminds me of Gary Larson.