The Ría Lagartos Biosphere Reserve is a UNESCO-recognised coastal ecosystem covering over 600 square kilometres of shallow lagoons, mangrove forests, salt flats, and beach. The reserve's most famous inhabitants are its Caribbean flamingos — thousands of birds breed in the protected salt pans, and boat trips bring visitors close enough to watch them feed by filtering brine shrimp through their bent bills.
The reserve also supports crocodiles, sea turtles nesting on the outer beach, ocelots, jaguars (rarely seen), and an extraordinary diversity of wading birds. Over 300 species have been recorded here, making it one of the best birding destinations in the Yucatán. Tours leave from the town waterfront with local boatmen who know the reserve intimately; most take two to three hours and cover the flamingo flats, the mangrove channels, and at least one crocodile-spotting stretch.