Great trip with Searious. Three snorkel stops, the park headquarters, beach barbeque. When we went there was a loggerhead going back out to sea after dropping her eggs. Willie picked her up, partially out of the water, so we could see her. Really cool. Definitely worth the time and money.
Bacalar Chico is a protected area and one must register and pay a fee (I think it is around $5.00 PP) at the park office located on the lagoon side of the island. There is a really cool model of the Bacalar area inside the park office. Lots of great snorkeling ,touring and the cut is interesting too, Very narrow in places. One of the few places where You can touch Mexico (Without a passport)