Isthmus & Boquerón Reef
Boat dive · Reef wall
Sheer cliff-like walls on Mona Island, fed by currents from the open Atlantic and draped in gorgonian sea fans and black corals.
About this site
Mona Island — often called the Galápagos of the Caribbean — lies about 50 miles off Puerto Rico and is reached by a long boat ride or, best of all, by liveaboard. Flushed by currents from the open Atlantic as well as the sheltered Caribbean, it enjoys exceptional visibility and marine biodiversity. The Isthmus and Boquerón Reef are the island's signature walls: sheer, cliff-like drop-offs where huge gorgonian sea fans and black corals hang in the current. Strong currents and depth make these dives best suited to experienced divers.
Marine life spotted here
- Gorgonian sea fans & black corals
- Reef sharks
- Sea turtles
- Large pelagics
- Clouds of reef fish
More in West Coast & Offshore Islands
Silver Banks & Southern Pride
Offshore sites visited by passing pelagics — sharks, leatherback sea turtles and dolphins. Conditions can be tough, best suited to experienced divers.
Mona Passage
The channel between Mona Island and the main island, where humpback whales pass through in the winter months — spectacular breaching and socialising in family groups.
Little Monita (Hobbit House)
An open-ocean seamount beside Mona Island visited by large numbers of sharks. Only diveable when sea conditions allow.