Black Grunt, Haemulon bonariense
Black Grunt, Haemulon bonariense. Commercial fish courtesy of Soriana’s Mercado, San José del Cabo, Baja California Sur, April 2019. Length 20 cm (7.9 inches). Note: this fish comes from the Gulf of Mexico, has been transported a long distance, is old and tired and not very photogenic.
The Black Grunt, Haemulon bonariense, is a member of the Grunt or Haemulidae Family, and is known in Mexico as ronco prieto. Globally, there are twenty-one species in the genus Haemulon, and all twenty-one are found in Mexican waters, fourteen in the Atlantic and seven in the Pacific Ocean.
The Black Grunt has and oblong compressed body that has a depth that is 36% to 40% of standard length. They have a bluish-silvery coloration and 18 narrow undulating black oblique lines on the body with a small black spot on the upper margin of the gill cover. The pectoral fins are transparent; all other fins are dusky to black. Juveniles have 2 long stripes on their body plus a short stripe above the eye. The head is deep with a convex upper profile on the nape, a small to moderate sized mouth with a finely serrated gill cover. Their anal fin has 3 spines and 8 or 9 rays, their caudal fin is forked; their dorsal fin is continuous with 12 spines and 14 or 15 rays. They have 18 to 24 gill rakers. They are covered with rough scales with the scale rows below the lateral line being oblique.
The Black Grunt is found in clear water over algal beds, coral reefs, grass beds, mangroves and mud intertidally and in the neritic zone at depths up to 30 m (100 feet). They reach a maximum of 40 cm (16 inches) in length. The juveniles consume amphipods, cladocera, copepods, and fish eggs. Reproduction is oviparous with distinct pairing during breeding season. They are stenohaline unable to survive changes in salinities. The Black Grunt 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 Grunt 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.
The Black Grunt is a fairly easy fish to identify due to its stripes. They are similar in body shape to the Latin Grunt, Haemulon steindachneri (subtle numerous bars, tail spot), and the Sailor’s Choice, Haemulon parra (similar barring, but bars are broken being composed of spots).
From a conservation perspective the Black Grunt is are currently considered to be of Least Concern, being widely distributed with stable to slightly decreasing populations. They are considered to be a quality food fish primarily sold in local fish markets fresh and salted, however, they are known to contain ciguatoxin. They are also utilized by the aquarium trade including public aquariums.