Pacific Goliath Grouper, Epinephelus quinquefasciatus
Pacific Goliath Grouper, Epinephelus quinquefasciatus. Underwater photograph taken at the Cabo Pulmo Marine Reserve, East Cape, Baja California Sur, August 2003. Photograph courtesy of Mark Rayor, Los Barriles, Baja California Sur. Mark commented: “We sighted this huge fish at a dive site called Las Casitas. It is in Cabo Pulmo National Marine Park near Iguana Beach. The location is about 50 feet deep and has unique rock formations with cavern-like pockets. It was a great surprise to encounter this huge Goliath Grouper. It was very social, not afraid of us, and stuck around for about 15 minutes while we watched and took pictures. My first guess was around 500 lbs. It may have been closer to 700 or 800 lbs. I tend to be conservative. We spent a lot of time close enough to touch. When it swam, its belly dragged in the sand.“
The Pacific Goliath Groupers vary in color as they grow in size. Specimens less than 1.0 m (3 feet 3 inches) in length are a greenish-brown color with a series of oblique dark brown bars along their sides. Larger fish are gray-green with a series of pale blotches and smaller dark brown spots scattered over their upper body, head, and pectoral fins. They have disproportionately tiny eyes, with a space that is flattened or depressed between them. Their anal fin has 3 spines and 8 rays and is rounded; and, their first dorsal fin has 11 spines, a gap and their second dorsal fin has 15 to 16 rays.
The Pacific Goliath Groupers are found in and around caves at depths up to 91 m (300 feet) but are normally located at depths of less than 30 m (100 feet). Juveniles and young adults inhabit fresh-water bays, lagoons, and estuaries. Adults are normally found around offshore reefs. They reach a maximum of 2.5 m (8 feet 2 inches) in length and 309 kg (700 lbs) in weight. They are highly territorial and feed predominately on crustaceans and lobsters, sea turtles, stingrays, and small fish. They do not sexually mature until reaching at least 1.0 m (3 feet 3 inches) in length. Since catch landings are dominated by fish that are less than 50 cm (18.5 inches), fish currently in the wild capable of reproducing are very limited. The Pacific Goliath 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 Pacific Goliath Groupers is a resident of Mexican waters of the Pacific but has a limited distribution being found from Magdalena Bay, Baja California Sur, southward along the southwest coast of Baja, in the lower two-thirds of the Sea of Cortez, and along the coast of the mainland south to Guatemala.
The Pacific Goliath Grouper can be confused with the Giant Sea Bass, Stereolepis gigas (straight caudal tail; large brown spots on sides; pointed anal fin) and the Spotted Cabrilla, Epinephelus analogus (large pupil size; uniformly distributed spots on body; 10 dorsal spines; curved and elevated space between eyes; four faint bars on sides).
From a conservation perspective the Pacific Goliath Grouper is currently considered to be Data Deficient and have not been formally evaluated. However, they are a major target of both commercial and recreational fishermen and due to this intense fishing pressure, they have undergone severe population reductions over the past 30 years. At present there is little information about their population size, however from extensive interviews with fishermen, landings of large adults ( 9 kg / 20 lbs to 91 kg / 200 lbs) are now almost never observed, whereas they were common 20 to 30 years ago. Contributing to the demise of this species is the fact that small individuals, landed only occasionally, fetch high market prices. As they are slow-moving and have no fear of humans they are taken routinely by commercial and recreational spear fishermen.