I just did the "Dunk-U" course yesterday.
www.dunk-you.com

This was the most interesting thing I have done in a long time. Gives a
whole new perspective to flying over water. Required by my pals at
www.angelflight.ca

Do they teach you about water survival too?

Should be required for all pilots in Hawaii. You can't fly a xcountry
that's 50 nm here without crossing large bodies of [sometimes
shark-infested] water.

Alex, PE in training.