The man with the bird on his helmet

Yesterday, on a truly beautiful fall day in NYC, my friend and I sat in Washington Square Park to soak up the sun and people watch. Watching one of those crazy live performances in the middle of the park, we couldn't help but be mesmerized by one gentleman in particular.

Sure, it's a fake bird, but I kept wondering what the purpose might be to have a fake bird on your helmet. Ideas, anyone??