Bottom fishing is the most effective method of catching gag grouper. Anglers commonly use depth sounders to locate rocky outcrops and irregular bottom where gags congregate, anchoring when a likely area is located. Wrecks and oil rigs in shallow shelf waters of the Gulf also attract many gag grouper. Trolling lipped diving plugs in shallower areas of rocky bottom or reef is also a very effective method to catch these fish. They are an excellent light-tackle target for those fishing relatively shallow waters and the white flaky flesh of this species makes it an excellent eating fish. The following are fishing methods used to catch this fish:
The coloration of this species is extremely variable but generally brownish gray overall with a pattern of dark, worm-like or kiss-shaped markings along the sides. Gags can be distinguished from black grouper, Mycteroperca bonaci, that often occur in the same habitat by the distinctive color pattern and the shape of the preopercle (the middle bone of the gill cover). The gag has a noticeably notched preopercle with a distinct lobed appearance while black groupers have an evenly rounded preopercle with no definite lobe below.