Chitales Reef

Two low patches of coral sit on a limestone base inside the Bay of Mujeres, with a channel of sand and coral rubble running between them.1 Grande is the larger; Chico lies 30 m to its south, a short swim across the channel, so a 40 to 60 minute dive can take in both. The maximum depth is 10 m, and the tops of the patches are shallower still.

At Grande, the centre-north took the worst of Hurricane Wilma. Skeletons of elkhorn coral still stand there, covered in algae, and French grunt and blue tang school around the patch, with more grunts at Chico. Sea fans and other gorgonians sway on the rock, mustard hill coral grows among them, brown algae cover much of the stone and seagrass spreads across the sand beside the reef. One island operator speaks of a steady south-east current almost year round.

Chitales has been the bay's reef for learning scuba diving for a long time, and the setting suits it: shallow, low in relief and a short boat run from either shore.1 It also holds a plain record of what a hurricane does to a reef. Wilma in 2005 damaged 49% of the coral colonies at Grande and 34% at Chico, and fish density at Grande appears to have fallen afterwards.1 The elkhorn skeletons in the centre-north of Grande are what that damage looks like today.

If the current is running, brief for a drift, stay with the guide and carry a surface marker buoy. The dead elkhorn is brittle and the rubble in the channel is sharp, so cross it with trim level and fins well off the bottom.

Helmet walking tours (the Breathing Operating Bubble, BOB) were permitted at Chitales Grande alone under the park's 2016 programme, so ask your operator whether one still works the reef the day you dive.