I love hearing the kookaburra "laugh" in Australia! This time I was lucky enough to see one "laughing" as well as hear it. It was in a built up area and there were at least 8 or 10 kookaburras, so I can imagine the local residents were not as intrigued as me. They really were making quite a racket.
It's beak is open as it "laughs" and is vibrating as well. I really needed to take a movie so you could appreciate the call.