Yucab Reef

Yucab starts over turtle grass and sand, and the pace drops there for the small animals. Stingrays lie in the grass and pufferfish hang above it. A seahorse is the animal to look for, and the occasional short bigeye turns up.

Then the reef builds. Coral heads and sponges stand out of the sand, cut by channels, with grunts and schoolmasters over them and French and queen angelfish drifting through. Along the outer edge a ledge runs with an overhang under it, the part that regular Cozumel divers single out. Spiny lobster sit in numbers around the ledges, and nurse sharks rest on the bottom and under them.

Somewhere in the second half a small swim-through opens out onto sand. How far the dive travels depends on the current and on your air, and on a strong day it can run as far as Tormentos reef next door.

Yucab is one of the Cozumel reefs where the splendid toadfish turns up, a fish of dens under coral at the line where reef meets sand. The species is IUCN Endangered. It is not strictly endemic to Cozumel, since a second locality is on record, but Cozumel is where divers go to see it.

The reef itself is a narrow strip, put at 10 to 20 m across, with coral heads standing 3 to 6 m off the sand and the interest at their base. That scale rewards slow looking: lobster in the ledges, the grass animals, a toadfish in a hole, a sleeping turtle on the flats.

Gloves and knives are prohibited in the park, so trim and buoyancy are your only tools near the coral, and the toadfish stays in its den.

Nitrox adds bottom time at these depths, so it is worth specifying when you book.