Crystal,
When you hear a swan and want to hear a Canada, your mind will let you believe it is a muted off tone goose. I can honestly say that one morning when the canadas were flying, I was hunting a-8, we needed one more goose for me. two birds honking and flying at us right out of the morning sun. Right as they approached shooting range my hunting buddy called me off the shot...I wanted them to be a goose, we both thought we heard goose. But my fatal flaw would have been that I could not identify the bird. If you can not identify the bird as being what you are after -->Don't shoot...