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Order Perciformes Family Serranidae(sea basses, groupers, fairy basslets) Giant grouper Epinephelus lanceolatus(Bloch, 1790). Max/270cm(TL), 400kg. Korean name/대왕바리 ChTaipei/鞍帶石斑魚 Global name/Giant grouper, Brindle grouper D/spine 11, soft ray 14 - 16; A/spine 3, soft ray 8. P1/soft-rays 18 - 20. P2/more or less normal.Lateral line scale(pored)/54 - 62. Scales in lateral series/95 - 105. Gill rakers/ 22 - 27
Distribution; Indo-Pacific: Red Sea to Algoa Bay, South Africa and eastward to the Hawaiian and Pitcairn islands, north to Jeju Island of Korea, southern Japan, south to Australia. Absence in the Persian Gulf is puzzling(source; fishbase.org). General; The giant grouper has a wide Indo-Pacific distribution, it is the most widely distributed species of grouper in the world. The giant grouper (Epinephelus lanceolatus), also known as the Queensland groper(grouper), brindle grouper or mottled-brown sea bass, is one of the largest extant species of bony fish. The body is fusiform and laterally compressed. 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 preopercle has a rounded corner and a finely serrated margin. The gill cover has a convex upper margin. Pelvic fins short, 2.3-2.7 in head length. Caudal fin rounded. The giant grouper can grow to huge size with the maximum recorded standard length being 270 centimetres, although they are more common around 180 centimetres, and a maximum published weight of 400 kilograms.
Colour: small juveniles(less than 15 cm) yellow, with 3 irregular black areas, the first from spinous dorsal fin to belly and chest and extending onto head, the second from base of soft dorsal fin to anal fin and the last at the peduncle. Subadults(25-60 cm) with irregular white or yellow spots on the black areas and fins with black spots; adults(90-165 cm) dark brown with faint mottling, the fins with numerous small black spots; large adults 180-250 cm) dark brown, fins darker.
Habitat and biology; The giant grouper is a species of shallow water fish and can be found at depths of 1 to 100 metres. It is associated with reefs and is the largest known bony fish found on reefs. Large specimens have been caught from shore and in harbours. 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 molluscs which are all swallowed whole. Fish which inhabit coral reefs and rocky areas favour spiny lobsters as prey; a 177-centimetre (70 in) specimen taken off Maui in Hawaii had a stomach content of two spiny lobsters and a number of crabs. Fish living in estuarine environments in South Africa were found to be feeding almost exclusively on the crab Scylla serrata. This species is normally solitary and long-lived. 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 as there have been reports of large specimen attacking humans.
Reproduction; Like most groupers, giant groupers are protogynous hermaphrodites. They spawn on a lunar cycle, with spawns lasting about 7 days. They are aggregative 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 diandric 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.
Use; The giant grouper is a highly valued food fish and is taken by both commercial and recreational fisheries. It is valued in Hong Kong as a live fish for the live reef food fish trade, especially smaller specimens, and its skin, gall bladder, and stomach, are used in Traditional Chinese Medicine. This species is cultured in mariculture 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.
The Registration of the Giant Grouper as a Korean Species; In 2009, an unidentified grouper caught by a set net in Gangjeong Port, Seogwipo, Jeju Island, was preserved as the first official specimen(SL/67~80cm). Based on research of this specimen, it was recorded as a previously unrecorded species in Korea, the "Giant Grouper(Epinephelus lanceolatus)", in 2013 (Myoung et al.). Its Korean name, Daewang-bari(대왕바리), literally translates to "Great King Grouper." The water depth where it was collected was 18m, and the water temperature at the time was approximately 17℃. According to a report published on the National Institute of Fisheries Science(NIFS) website in November 2021, research into crossbreeding the heat-tolerant tropical-subtropical Giant Grouper with native Korean groupers(Epinephelus akaara and Epinephelus bruneus) is reaching a successful stage. This is explained as a countermeasure for Korean species that suffer significant damage from high water temperatures caused by global warming. Experiments revealed that these hybrid groupers do not die even in high water temperatures of 35°C; instead, they grow faster at 28°C, reaching a marketable size of 1 kg within a single year.
The Story of Bubba: The Fish Treated for Cancer; The giant grouper was the first fish to receive chemotherapy, and the protagonist was a giant grouper named "Bubba" who lived at the Shedd Aquarium in Chicago. One day in 1987, an anonymous donor left a bucket containing a fish at the entrance of the Shedd Aquarium along with a note. The note requested that the fish be raised there. This fish, about 25 cm long, was a juvenile giant grouper(Epinephelus lanceolatus). Giant groupers are protogynous hermaphrodites, meaning most are born female and some later change sex to male. The donated juvenile was female at the time but transitioned to male in the mid-1990s. While living in the "Wild Reef" shark exhibit, the fish grew to a weight of about 70 kg, leading aquarium staff to call him "Bubba," a nickname meaning a large man with a dignified manner.
In 2001, Bubba developed an unusual growth on his forehead, which was eventually diagnosed to be malignant; the aquarium called in veterinarians to remove the growth surgically and treat Bubba with chemotherapy that year, and again in 2003, when it regrew. Shedd officials stated that Bubba was popular with cancer survivors, especially children, and was a favorite of visitors. The oncology department of Hope Children's Hospital in Oak Lawn, Illinois, recognized Bubba with a tile in the ward. Bubba died on August 22, 2006, presumably due to problems with his health that were related to his old age and medical history.
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