The head and body are gray or greenish marked with pale blotches and small dark spots which are scattered over the upper head and body, as well as being on the pectoral fins. Subadult fish which are less than 100 centimeters (39 in) in length are overall greenish to tawny brown with diagonal, irregular darker brown bars on the body and caudal fin.
The juveniles have heavy spotting on the head, the portrayed part of the dorsal fin and the pectoral, pelvic, and caudal fins, They have 5 diagonal black bars on the body which reach onto the dorsal and anal fins and there is a black bar on base of the caudal fin. This is one of the largest species of grouper, attaining a maximum total length of 250 centimeters (98 in).
The Pacific Goliath grouper is found on offshore rocky reefs as adults, although it has also been recorded in inshore areas. The juveniles inhabit mangroves, estuaries, lagoons and bays.
It has been recorded feeding on sharks, rays, crustaceans, cephalopods, other fishes and even sea snakes and mammals. Little is known about its biology but it is thought to be similar to the Atlantic Goliath grouper.
The Pacific Goliath grouper is a sought after quarry species for recreational and commercial fisheries in the entirety of its range. It has declined over much of its range, and, in Colombia smaller Goliath groupers of lengths less than 30 centimeters (12 in) are regarded as the most valuable.
This leads fishermen to target small and sexually immature groupers which threatens the local survival of the species by taking the fish they get an opportunity to reproduce. IUCN Red List of Threatened Species.
Groupers of the world (family Serranidae, subfamily Epinephrine). “Goliath Pacific groupers under threat in a biodiversity hotspot”.
Gulf grouper are large fish that live in shallow, coastal areas during their first 2 years of their life, before moving on to rocky reefs and kelp beds. Gulf grouper used to be very common in the eastern Pacific Ocean, but they became scarce because commercial and recreational fisherman could easily catch them.
Their abundance has severely declined since the mid-20th century primarily because of direct harvest by commercial and artisanal fisheries. Outside a known population in Bahia Magdalena, there is no published evidence of gulf grouper along the Pacific coast of the Baja California peninsula.
Adult gulf grouper are mainly found around rocky reefs, underwater mountains, and kelp beds. Gulf grouper are also likely protogynous hermaphroditic, which means that they mature as females and later transition into males.
Adult gulf grouper gather in large groups to reproduce once per year. They gather at reefs and underwater mountains and form spawning aggregations from April to June.
Activities that may degrade their habitat include the release of contaminants, such as urban runoff, wastewater, or oil and gas spills. Pollution can also reduce the amount of oxygen in the water or deliver chemicals that are toxic to these fish.
Physical barriers, such as shoreline and offshore development can also threaten gulf grouper by limiting their access to important breeding or feeding areas. Overfishing Direct harvest of gulf grouper, especially at spawning aggregation sites, is the biggest threat to the species.
This means that there are fewer male groupers left in the oceans, which makes reproduction more difficult. Underwater photograph taken at the Cab Pull Marine Reserve, East Cape, Baja California Sur, August 2003.
Photograph courtesy of Mark Mayor, Los Bar riles, Baja California Sur. Mark commented: We sighted this huge fish at a dive site called Las Capital.
Globally, there are 100 species in the genus Epimetheus, of which 11 are found in Mexican waters, 6 in the Atlantic and 5 in the Pacific Ocean. 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 are highly territorial and feed predominately on crustaceans and lobsters, sea turtles, stingrays, and small fish.
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 Baa, in the lower two-thirds of the Sea of Cortez, and along the coast of the mainland south to Guatemala. 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. Contributing to the demise of this species is the fact that small individuals, landed only occasionally, fetch high market prices.
The giant grouper has a robust body which has a standard length equivalent to 2.4 to 3.4 times its depth. The dorsal profile of the head and the intraorbital area are convex, The properly has a rounded corner and a finely serrated margin.
The gill cover has a convex upper margin. There are 11 spines and 14-16 soft rays in the dorsal fin while the anal fin has 3 spines and 8 soft rays.
The adults are greyish-brown in color overlain with a mottled pattern and with darker fins. The giant grouper can grow to huge size with the maximum recorded standard length being 270 centimeters (110 in), although they are more common around 180 centimeters (71 in).
And a maximum published weight of 400 kilograms (880 lb). The giant grouper is a species of shallow water and can be found at depths of 1 to 100 meters (3.3 to 328.1 ft).
Large specimens have been caught from shore and in harbors. They are found in caves and in wrecks while the secretive juveniles occur in reefs and are infrequently observed.
The adults are mainly solitary and hold territories on the outer reef and in lagoons. They have also been caught in turbid water over silt or mud sea beds by prawn fishermen.
The giant grouper is an opportunistic ambush predator which feeds on a variety of fishes, as well as small sharks, juvenile sea turtles, crustaceans and mollusks which are all swallowed whole. Fish which inhabit coral reefs and rocky areas favor spiny lobsters as prey and 177 centimeters (70 in) specimen taken of Maui in Hawaii had a stomach contents of two spiny lobsters and a number of crabs.
Fish living in estuaries environments in South Africa were found to be feeding almost exclusively on the crab Scylla errata. They are, however, curious and frequently approach divers closely.
They are not generally considered dangerous to humans but divers are advised to treat large specimens with caution and not to hand feed them. They are aggregate broadcast spawners, usually with several females per male.
Studies in captive populations suggest that the dominant male and female begin the spawning event as nearly the only spawners for the first day or two, but other members of the aggregation fertilize more eggs as the event progresses, with even the most recently turned males fathering offspring. Giant groupers are diabetic protogynous hermaphrodites, meaning that although some males develop from reproductively functional females other males start to produce sperm without ever having gone through a phase as a reproductive female.
The giant grouper is a highly valued food fish and is taken by both commercial and recreational fisheries. As well as the consumption of its flesh its skin, gall bladder and stomach are used in Traditional Chinese Medicine.
It is valued in Hong Kong as a live fish for the live reef food fish trade, especially smaller specimens. This species is cultured in agriculture and this practice is widespread but there is a restricted supply of juveniles, although hatcheries in Taiwan have produced captive bred juveniles, exporting some for to be grown on in other parts of South-East Asia.
Many of the fish produced in aquaculture are hybrids between this species and E. fuscoguttatus. IUCN Red List of Threatened Species.
“A study into parental assignment of the communal spawning protogynous hermaphrodite, giant grouper (Epimetheus lanceolatus)”. ^ Peter Palma; Akihito Nakamura; Garden XYZ Libunaoa; et al. (2019).
“Reproductive development of the threatened giant grouper Epimetheus lanceolatus “. ^ Scholar, W. N.; Cricket, R. & van der Loan, R.