The whoo-hoo.........is called the wolf whistle! My Popcorn is great at it! I'll whistle it to him, and he'll whistle it back! Its soooo cute and funny! He also knows how to whistle the cell phone melodies, part of *Mary had a little lamb*......... and several other things that I can't figure out...........but he whistles all day and it sounds just beautiful! He has his personalized cockatiel whistles too, that are basically a combination of everything he knows plus his own birdie whistles. I can't imagine a house without those daily whistles!

Muffin can whistle too, but not that much. She's a sweet little girl who prefers to squack back when I talk to her, than whistle.