The gill cover has a convex upper margin. The adults are greyish-brown in color overlain with a mottled pattern and with darker fins.
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).
Although some populations are below target levels, U.S. wild-caught red grouper is still a smart seafood choice because it is sustainably managed and responsibly harvested under U.S. regulations. Fishing gear used to catch red grouper rarely contacts the ocean bottom and has minimal impacts on habitat.
They engulf prey whole by opening their large mouths, dilating their gill covers, rapidly drawing in a current of water, and inhaling the food. Large sharks and carnivorous marine mammals prey on adult red grouper.
Red grouper are found in the western Atlantic Ocean from Massachusetts through the Gulf of Mexico and south to Brazil. Annual catch limits are used for red grouper in the commercial and recreational fisheries.
Both the commercial and recreational fisheries have size limits to reduce harvest of immature red grouper. The commercial and recreational fishing seasons are closed from January through April to protect red grouper during their peak spawning period.
To reduce by catch, there are restrictions on the type of gear fishermen may use and where they can fish. Minimum size limits protect immature red grouper.
The red grouper has a body with a standard length which is 2.6 to 3 times as long as it is deep. The properly is subangular with the serrations at its angle being slightly enlarged and the upper edge of the gill cover is straight.
The They are dark reddish brown on the upper part of the head and body, shading to paler pink on the underparts, they are marked with lighter spots and blotches across their body and there are darker margins to the fins. This species has a maximum published total length of 125 centimeters (49 in), although they a more commonly found at lengths around 50 centimeters (20 in), and a maximum published weight of 23 kilograms (51 lb).
The redgrouper's typical range is coastal areas in the western Atlantic, stretching from southern Brazil to North Carolina in the US and including the Gulf of Mexico and Bermuda. The red grouper is a reversal, largely sedentary species which has an extended (~40 day) pelagic larval stage before it settles in shallow coastal hard bottom habitat as juveniles.
While primarily eating benthic invertebrates, the red grouper is an opportunistic feeder in the reef community. The diet commonly includes mantid and portend crabs, juvenile spiny lobster, and snapping shrimp, with the occasional fish.
The red grouper is of moderate size, about 125 cm and weighs 23 kg or more. When aggravated (they are highly territorial) or involved in spawning activities, these fish can very rapidly change coloration patterns, with the head or other parts of the body turning completely white, and the white spots appearing more intense.
Red grouper (Epimetheus Mario) on an excavated site on Pulley Ridges on the West Florida Shelf Red grouper actively excavate pits in the seafloor. They start digging in the sediment from the time they settle out of the plankton and continue throughout their lifetime.
They use their caudal fin and their mouths to remove debris and sediment from rocks, creating exposed surfaces on which sessile organisms actively settle (e.g., sponges, soft corals, algae). The exposure of structure also attracts a myriad of other species, including mobile invertebrates and a remarkable diversity of other fishes, from bodies and butterfly fish to grunts and snapper.
The lionfish Steroid Holsteins started invading red grouper habitat by 2008, from Florida Bay to the Florida Keys and offshore to Pulley Ridge, a despotic coral reef on the West Florida Shelf west of the Dry Tortugas. Known for being extremely capable predators on small reef fish, scientists are very interested in determining the extent to which their invasion changes the functional dynamics of associated communities.
Smithsonian Marine Station at Fort Pierce. “Helming parasites of Epimetheus Mario (Pisces: Serranidae) of the Yucatán Peninsula, southeastern Mexico” (PDF).
Red grouper is available year-round with peak catches in the Atlantic and Gulf of Mexico occurring during the summer and fall. Red grouper flesh is white and lean with a notable lack of bones, and is very forgiving when cooked as it remains moist, firm, and has large flakes.
Red grouper are protogynous hermaphrodites, meaning they all begin life as a female and eventually some may transform into males. Red grouper have large mouths with a slight under-bite, which allows them to eat their prey whole by dilating their gill covers and rapidly inhaling.
Red grouper act as “marine engineers” in their ecosystem by hollowing out flat-bottomed areas to create their home and attract mates. This process provides habitat to other species such as spiny lobster, black grouper, red porgy, and vermilion snapper.
Allocates an annual catch limit between commercial (76 percent) and recreational (24 percent) fishers Restricts certain gear types to reduce by catch Sets minimum size restrictions to protect immature red grouper Establishes year round and seasonal area closures for both commercial and recreational fishers to protect spawning stock and essential fish habitat The If program allocates shares of the total commercial catch limit amongst individual fishers.
Under the program, each fisher owns a share of the quota and can choose to fish it at anytime during the open season. Strict commercial reporting requirements prevent fishers from harvesting more than their individual allocation.
The Reef Fish FMP has been a success in allowing red grouper populations to bounce back from overfishing that had occurred on and off in the Gulf since the 1970s. They are fairly long-lived and come together to spawn in large numbers, characteristics that make them vulnerable to fishing pressure.
The Gulf of Mexico population in the was declared overfished in 2000 and then was rebuilt to target levels in 2007, according to the U.S. National Marine Fisheries Service. The South Atlantic stock is no longer overfished, but a 2010 assessment showed it hasn’t been fully rebuilt.
Grouper fisheries have high impacts on nontarget species, the Monterey Bay Aquarium reported. Venting tools are also employed to make it easier for reef fish to survive when released.
In the United States, red grouper management measures include permits, annual catch limits, fishing quotas, marine protected areas that are closed to fishing, seasonal closures, gear restrictions, minimum size limits, and data reporting requirements. Its range includes the Gulf of Mexico and Florida Keys in the United States, the Bahamas, most of the Caribbean, and most of the Brazilian coast.
Scientists from our Southeast Fisheries Science Center are working to understand the changes that have occurred in coral reef ecosystems following the loss of top predators, such as groupers. From 1997-2005, our researchers collaborated with Florida State University's Institute for Fishery Resource Ecology (Dr. Chris Koenig and Dr. Felicia Coleman) to monitor the status and recovery of Goliath grouper.
This Goliath grouper research program investigated juvenile and adult Jewish abundance, distribution and migration patterns; their age and growth; and their habitat utilization. With the help of Don Maria we have tagged over 1,000 adult Jewish and have observed aggregations of Goliath grouper in both the Gulf of Mexico and more recently, the South Atlantic.
Posters created by the Center of Marine Conservation help disseminate information about our project and its requirements, highlighting our tagging study and the morphology of Goliath grouper. Given that these groupers were afforded protected status, researchers worked to utilize and develop novel non-lethal techniques to procure and analyze biological samples for life history information.
Researchers have also determined that soft dorsal rays hold promise for aging older fish (Marie et al., 2008). These casualties, resulting from red tide, gave our biologists a unique opportunity to collect a multitude of biological samples, without having to sacrifice healthy animals.
From these decomposing carcasses, biologists were able to record length for use in an age/length relationship, and were able to extract monoliths and remove dorsal spines and rays for comparison of hard parts in age and growth analysis. Tissue samples were also removed and sent to the Florida Marine Research Institute, so they could evaluate the level of red tide toxin.
The sampling trip gave these biologists an opportunity to educate the curious beach goers about red tide and Goliath grouper (a few of which had been misidentified as baby manatees). Attempts to evaluate the data needed to assess the status of these depleted stocks and develop rebuilding plans present unique challenges.
In 2010, the Florida Fish and Wildlife Conservation Commission and NOAA Fisheries convened a benchmark Goliath grouper assessment for the continental U.S. population. This project would not have been possible without ongoing collaboration with researchers from Florida State University, Everglades National Park, and the recreational fishing and SCUBA diving communities.