Black Grouper

Black Grouper, Mycteroperca bonaci

Black Grouper, Mycteroperca bonaci, Juvenile. Fish caught from coastal waters off Islamorada, Florida, January 2016. Length: 15 cm (5.9 inches). Catch, photograph, and identification courtesy of Josh Leisen (joshadventures.com), Gaylord, Michigan.

Black Grouper, Mycteroperca bonaci, Juvenile. Fish caught from coastal waters off Big Pine Key, Florida, April 2019. Length: 15 cm (5.9 inches).  Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.

Black Grouper, Mycteroperca bonaci, Juvenile. Fish caught from coastal waters off Sewalls Point, Florida, January 2023. Length: 16 cm (6.1 inches). Catch, photograph and identification courtesy of Doug Bomeisler, Fort Pierce, Florida.

Black Grouper, Mycteroperca bonaci, Juvenile. Fish caught Fish caught off the Channel 5 Bridge (MM 71.4), Florida Keys, Florida, January 2014. Length: 17 cm (6.7 inches). Catch, photograph and identification courtesy of Ryan Crutchfield, Tampa, Florida.

Black Grouper, Mycteroperca bonaci, Juvenile. Fish caught from coastal waters off Islamorada, Florida, January 2016. Length: 30 cm (12 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).

Black Grouper, Mycteroperca bonaci. Fish caught from coastal waters off southwest Florida, December 2014. Length: 88 cm (2 feet 11 inches). Catch, photograph and identification courtesy of Ben Cantrell, San Diego, California.

The Black Grouper, Mycteroperca bonaci, is a member of the Grouper or Epinephelidae Family, and is known in Mexico as cherna negrillo. Globally, there are fifteen species in the genus Mycteroperca, of which eleven are found in Mexican waters, seven in the Atlantic and four in the Pacific Ocean.

The Black Grouper has an elongated, robust, and compressed body with a depth that is 27% to 31% of standard length. They are an olive gray or gray in color with  rectangular dark gray blotches on their sides. Their anal, caudal fin and outer third of the second dorsal fins are black and their pectoral fins have yellow or white margins. Their head has a long snout, a projecting lower jaw and the preopercle is evenly rounded (a key to identification). Their anal fin has 3 spines and 11 to 13 rays; their caudal fin is straight; their first dorsal fin has 11 spines; and, their second dorsal fin has 15 to 17 rays. They have 17 to 24 gill rakers.

The Black Grouper found in coastal areas within reefs, and rocky areas at depths between 6 m (20 feet) and 75 m (250 feet). Larger individuals are found at greater depths than smaller individuals. Juveniles are found in estuarine seagrass, mangroves, and oyster rubble. Females range in length from 16 cm (6.1 inches) to 1.31 m (4 feet 4 inches) and males from 95 cm (3 feet 2 inches) to 1.52 m (6 feet 0 inches). They can be up to 100 kg (220 lbs) in weight. As of January 1, 2023, the International Game Fish Association world record stood at 56.2 kg (124 lbs) with the fish caught from coastal waters off Texas in January 2003. They are normally found as solitary individuals. The adult Black Grouper consumes other fishes (grunts, herrings, and snapper targeting their spawning aggregations) and squid; the juveniles primarily consume shrimp and other crustaceans. In turn the adults are preyed upon by numerous sharks and the juveniles are preyed upon by other groupers and moray eels. They are protogynous hermaphrodites. The majority begin life as females and at mid-life, some transition into males. Their reproduction times are lengthy as they are slow to mature. The transition normally occurs in fish that are 1.0 m (3 feet 3 inches) in length and about fifteen years in age. The population is normally one male for every four females. Reproduction is oviparous and occurs with seasonal spawning aggregations with large numbers of individuals. Fertilization is external and the eggs and larvae are pelagic. They have life spans of thirty-three years. A Grouper Family Weight From Length Conversion Table has been included on this website to allow the accurate determination of a fish’s weight and if undersize, a return to the ocean unharmed. The Black Grouper is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

The Black Grouper is most likely confused with the Gag Grouper, Mycteroperca microlepis (serrated preopercle), the Scamp, Mycteroperca phenax (lunate tail),  the Western Comb Grouper, Mycteroperca acutirostris (darky wavy stripes under the eyes), the Yellowfin Grouper, Mycteroperca venenosa (pectoral fin margin bright yellow), and the Yellowmouth Grouper, Mycteroperca interstitialis (yellow upper lip).

The Black Grouper is a resident of all Mexican waters of the Atlantic Ocean including the Gulf of Mexico and the east coast of the Yucatán Peninsula in the Caribbean.

From a conservation perspective the Black Grouper is currently considered to be NEAR THREATENED with a 30% decline in populations over the last ten years. Historically they have been heavily targeted by both commercial and recreational fishermen, especially when they aggregate for spawning. They also have long maturity times. The Mexican Government has imposed regulations on commercial fishing that include annual quota limits, commercial minimum size limits, seasonal closures and the ban of sales during spawning season. Recreational regulations include minimum size limits, daily bag limit of five groupers per person; and seasonal closures. They are considered to be a prized food fish but are also known to contain ciguatoxin. They are also utilized by the aquarium trade  on a limited basis and can be found in large public aquariums.