[9] The adult females and the juveniles are normally pale grey to brown-grey marked with darker blotches and wavy lines that give a marbled appearance to the upper flanks and back.

When resting they often assume a camouflage pattern with 5 dark brown saddles separated by white bars along the base of the dorsal fin.

The large adult males are typically pale to medium grey in colour, with an indistinct reticulated pattern underneath the dorsal fin.

The northern population is found around Bermuda and along the eastern coast of the United States from North Carolina south to Yucatan Peninsula of Mexico[8] but it is largely absent from Cuba, apart from one record of a vagrant.

They have been recorded producing thumping sounds when under stress, this is done by vibrating the swim bladder using muscular contractions.

[9] The fishes preyed upon are largely herring, sea bream, jacks and pompanos, drums and grey mullet.

[6] This species is a protogynous hermaphrodite; all fish start life as females, attaining sexual maturity between the ages of 5 and 6 years old and having reached a total length of 67 to 75 centimetres (26 to 30 in), they will spawn at least once and then some will change sex and become males.

[10] The gag grouper is targeted by commercial and recreational fisheries using handline, bottom longline and speargun.

Fishermen target the spawning aggregation while the juveniles are frequently caught as bycatch in the bait-shrimp fishery that fishes over sea grass beds.