I paddled in one of these races a few years ago in the northern part of Kyoto. They called them dragon canoes. They were really heavy and although a lot of fun, certainly not very competitive. I met another Canadian there and asked how long his team had been practicing. He looked at me blankly. I then saw him paddling around warming up with his hands on the wrong ends of the paddle (holding the blade like a righty but sitting on the left).
Dragon boating in Japan is fun (especially hearing all the commands in english), I'd recommend it if any of you ever go.