If you're on the island you already know about this one. If you're doing a day trip though and haven't paid to feed the dolphins - it's almost as magical just to watch the wild tangalooma dolphins playing in their habitat.
The feedings start shortly after sunset so just make your way over to the jetty about then to catch the show.
The wildlife team are great throughout the show and will talk you through who each of the dolphins are and their back stories.
Get there early to get a decent seat otherwise you'll be standing around for most of it.