Schoolmaster Snapper in Cozumel

A yellow-finned snapper that hangs in loose groups under ledges and around coral heads, facing into the current and watching you rather than fleeing.

Quick ID

How To Identify It

Pale grey-brown body crossed by faint lighter bars, bright yellow fins, and a distinct blue line under the eye that fades in older fish. The tail is yellow and slightly forked.

Where You Will See It In Cozumel

Schoolmaster Snapper is tagged on reef profiles right along the west coast, across a depth band of roughly 16 to 82 feet.

Without a boat. It turns up at Chankanaab Shallow and Playa Corona — all shore entries, so you dive them on your own schedule.

On an ordinary beginner boat dive. It is recorded at Yellow House, Yucab, Chankanaab Bolones, Columbia Shallows and La Francesa. No advanced certification needed.

Deeper, and on the walls. It also shows up on Palancar Horseshoe, Paso del Cedral, Punta Tunich and Tormentos.

Conditions change the odds more than the site does — the current, the time of day and how much the group has already stirred up the sand. Ask your guide what they have been seeing that week.

Behaviour

Sits in loose aggregations by day and hunts at night, taking small fish and crustaceans. Schoolmasters are territorial about a particular ledge and will hold position rather than bolt.

Commonly Confused With

• Mahogany snapper — Smaller, with a dark blotch high on the flank and red-tinged fins.
• Grey snapper — Duller fins, no yellow, and a more slender profile.
• Yellowtail snapper — Yellow stripe down the side and a deeply forked yellow tail; it swims mid-water, not under ledges.

Diving Etiquette And Safety

Keep fins off the reef and hands to yourself. Nothing here needs to be touched, moved or provoked to be seen well.

Part of the Cozumel marine life guide · see Cozumel dive sites · plan your Cozumel dive trip

Photo courtesy of the Cozumel Coral Reef Restoration Program, used with permission.