We did this last year with our 2 y.o. However, we bought tickets directly from the place (you can also purchase online) and took a cab from the port. It was cheaper than the excursion price and we didn't want to commit to plans in advance because the weather was looking iffy. FYI, you can buy tickets for the whole park including the pool and snorkeling, or just the turtles. We enjoyed the turtles, but it was pretty limited. We were there barely an hour. Would rather have gone to the beach for sand/surf.