Smallmouth Grunt in Cozumel

Yellow stripes on silver, a yellow tail, and a mouth noticeably smaller than the other grunts. They hang in tight groups in the shade, often more tightly packed than French grunts.

Quick ID

How To Identify It

Silver-white body with straight yellow horizontal stripes running the full length, all fins yellow, and a small mouth. The stripes do not diverge below the lateral line.

Where You Will See It In Cozumel

Smallmouth Grunt is tagged on reef profiles right along the west coast, across a depth band of roughly 6 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 Yucab, Chankanaab Bolones, Columbia Shallows, La Francesa and Las Palmas. No advanced certification needed.

Deeper, and on the walls. It also shows up on Chun-Chacaab, Maracaibo, Palancar Horseshoe and Paso del Cedral.

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

Rests by day and moves out to feed on plankton and small invertebrates at night. It takes smaller prey than other grunts, which is what the reduced mouth is for.

Commonly Confused With

• French grunt — Larger mouth, and the lower stripes run diagonally rather than straight.
• Bluestriped grunt — Blue on yellow, with a dark tail.

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.