I'm no sure either but I booked through shore excursions group? I think. Definitely don't wait until the day of. We had people on our trip who were not able to get what they wanted. I will say the turtle swim was awesome. It was about an hour, they do a quick 10-15 minute intro of how to touch the turtles, habitat, etc. I think everyone has to be 5 ft maybe? It says in the description. When you get in you have to go to one spot so they can film and also so the turtles know you are there to play with them. They are very interactive and HUGE. They don't look that big but they are... and heavy. Good luck. I loved the guy who ran our time in the turtle cove and thought he did a great job. I hear rave reviews about the sea trek and sea lions too! It was tough to decide what we wanted.