Black Grouper in Cozumel
Black Grouper (*Mycteroperca bonaci*) in Cozumel: how to identify it, where it is reliably seen, and what it is commonly confused with.
A large, dark, powerfully built grouper marked with rectangular chain-link blotches over a brassy-grey body, and a squared-off tail with a thin pale edge.
Quick ID
| Scientific name | Mycteroperca bonaci |
|---|---|
| Group | Predators & Big Fish |
| Typical size | 70–130 cm on Cozumel reefs |
| Depth range | 10–40 m |
| When to see it | Year-round |
| Active | Daytime |
| Conservation status | Vulnerable |
| Notes | — |
Where You Will See It In Cozumel
The deeper walls — Santa Rosa, Colombia Deep and Punta Sur — where large individuals hold station near the drop-off.
Reliable sites: Santa Rosa Wall, Colombia Deep, Punta Sur.
Behaviour
More mobile and more wary than the Nassau grouper. Frequently seen being cleaned at cleaning stations, mouth and gills held open while gobies and shrimp work.
Commonly Confused With
- Nassau grouper — Nassau has clean vertical bars and a black saddle on the tail base.
- Yellowfin grouper — Yellowfin shows yellow along the outer edge of the pectoral fins.
Diving Etiquette And Safety
Give cleaning stations space. A grouper holding its mouth open is mid-service, and swimming in ends the interaction for every fish there.
Part of the Cozumel marine life guide · see Cozumel dive sites · plan your Cozumel dive trip
Photo: Bernard DUPONT, CC BY-SA 2.0, via Wikimedia Commons.
