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Atlantic Goliath Grouper
The Atlantic Goliath Grouper – scientific name Epinephelus itajara – is a massive saltwater fish found in the Gulf of Mexico, the Atlantic Ocean, and the Caribbean Sea. Other common names for this fish include hamlet, giant seabass, goliath grouper, black bass, jewfish, southern jewfish, and esonue grouper.
There are also multiple names in other languages, including Portuguese, Italian, Spanish, Norwegian, Japanese, Polish, Turkish, Palicur, Italian, Greek, Finnish, German, and Icelandic.
Characteristics & Appearance
To be able to identify an Atlantic Goliath Grouper, you have to understand the unique features that make it stand out from other grouper species.
Weight & Length
Atlantic goliath grouper may grow as long as eight feet and weigh nearly 800 pounds, making it the largest type of grouper in the Atlantic Ocean.
Males are larger than females and mature faster, although both sexes of this species face a slow growth rate of around four inches each year until the age of six. Then growth slows to around 1.2″ each year until the age of 15. By the time a Goliath is 25 years old, they are growing less than .4″ a year.
A male goliath will be between 43 and 43 inches by the time they reach sexual maturity, whereas females will be between 47″ and 53″ at sexual maturity. Males reach maturity earlier, which is why they are smaller than females at the time of maturity.
Physical Characteristics & Color
This grouper species has a thick, elongated body, a broad head with small eyes, and a rounded snout. They also have continuous dorsal fins with longer soft dorsal rays than the first dorsal fin’s spines.
There are also rounded pectoral fins bigger than the pelvic fins, a rounded caudal fin, and scales cover the anal fins and soft dorsal bases. They also have short tail fins that resemble a fan.
An Atlantic goliath grouper’s color is usually mottled brownish-yellow, although some may appear gray or olive. Dark spots and bards on the body, fins, and head make it easier for this species to hide unseen in their preferred habitats of muddy inshore or rocky corals.
On fish shorter than three feet, there are three to four irregular vertical bars along the sides. Another bar covers the rear part of the caudal penduncle.
This species of grouper also has between three to five rows of teeth along the lower jaw. Short, weak canine teeth help distinguish this grouper from other grouper species.
Juvenile Atlantic Goliath Grouper is a lighter tawny color with attractive blotches and irregular dark vertical bands.
Most groupers are born as females and morph into males over time. But there is a wide debate about this species’ protogynous hermaphrodite, so this may change with further research.
Lifespan & Reproduction
Although it’s difficult to pinpoint exactly, the common belief is that Atlantic Goliath Grouper can live up to fifty years or longer in the right conditions. However, the oldest Goliath on record was 37 years old.
Males reach sexual maturity when they’re between four and six years old and around 45″ long, whereas females can take up to six to eight years and be around 49″ in length.
The moon’s lunar cycle plays a major role in the spawning season for Goliath grouper, occurring during the summer from July to September. They spawn immediately after a full moon.
During the spawn, more than 100 groupers converge into offshore spawning aggregations on locations like isolated reef patches, shipwrecks, or rocky ledges to spawn.
During this time, females release their eggs while males drop sperm into the water above deep reefs. This process is called broadcast spawning.
Once fertilization occurs, the eggs become pelagic and get dispersed by water currents. Goliath starts as kite-shaped larvae and transforms into 1″ benthic juveniles between 25 to 26 days after hatching.
Knowing where to find Atlantic Goliath Grouper is useful for helping track the population and habits of the Atlantic Goliath Grouper. It also reduces the risk of you illegally capturing one of these non-sport fish.
Where Do Atlantic Goliath Grouper Live?
Atlantic Goliath Groupers prefer shallow warm waters where there are artificial or coral reefs. This species exists in the US around the Florida Keys and the Gulf of Mexico. There have been some occasions where this species travels as far north as the coast of Maine and New England, Massachusetts.
Further south, they live in the Caribbean Sea, including most of the Caribbean, along most of the Brazilian coastline, and the Bahamas.
On the other side of the Atlantic ocean, Atlantic Goliath Grouper lives along Africa’s west coast from Senegal to the Congo.
Food & Diet
Understanding the diet of the Atlantic Goliath Grouper allows for better protection for the species by ensuring there are plenty of prey for this species to consume.
What Do Atlantic Goliath Groupers Eat?
Atlantic grouper enjoy a wide range of seafood, although a large portion of their diet comes from crustaceans like shrimp, crab, and spiny lobsters. They also feed on various fish species, including parrotfishes and stingrays, young sea turtles, and octopuses.
Large Goliath Grouper may feast on barracudas and sharks, including the lemon shark known for its large size.
This species catches its prey by blending in with its surroundings and ambushing its catch with a quick dart and a snap of its teeth. The sharpened rows of teeth make it easy to catch and keep prey in their mouth to prevent escape.
Despite having so many teeth, these fish do not chew their prey. Their mouth’s wide size allows them to create negative pressure, which sucks in fish and other prey. They can then easily swallow their food whole.
Threats & Predators
Despite the size of the Atlantic Goliath Grouper, they do face a few different threats and predators.
Due to the meat’s flavor, Atlantic Goliath Grouper has suffered major overfishing that has led them to become endangered.
A major threat for this species is spearfishing, as they stay in shallow water near reefs and are not afraid of humans’ presence. And because they spawn in the same location each year, it’s easy to mass harvest them during the breeding season.
Climate Change & Global Warming
Climate change and global warming have a major impact on the waters where these fish live. As the ocean gets warmer, more harmful bacteria, pathogens, and parasites grow.
Goliath grouper who live in the eastern Gulf of Mexico is at significant risk of being poisoned by red-tide blooms caused by toxic phytoplankton named Karenia Brevis. Red-tide blooms occur seasonally and affect shallow water.
Since Atlantic Goliath Grouper are so large, they have few natural predators. However, there are a few larger species that can pose a threat. King mackerel, barracuda, moray eels, and other groupers pose the most risk. Sharks like the sandbar and great hammerhead also feed on Atlantic Groupers.
Another factor that threatens the repopulation of the Atlantic Goliath grouper species is their biological makeup. These fish grow slowly and take multiple years to become sexually mature and ready to breed.
They also have a low reproductive rate, which also affects repopulation. However, due to the protective action, this species is slowly becoming more abundant.
The Atlantic Goliath Grouper is a Critically Endangered species, as determined by the World Conservation Union (IUCN). According to their studies, this species has undergone a population reduction of 80% or more within the last ten years or three generations.
In the Gulf of Mexico, this species is “vulnerable” and “endangered” with a zero-tolerance policy for harvesting. Protection for the Atlantic Goliath Grouper began in the US in 1990, and the Caribbean followed suit in 1993.
Fun Facts About Atlantic Goliath Grouper
- Because Atlantic Goliath Grouper grow so massive, a group of these fish can pose a danger to humans. There have been reports of these fish attacking divers,
- The largest Goliath Grouper ever caught with a hook-and-line weighed 680 pounds. This fish was caught in Fernandina Beach, Florida, in 1961.
- Breeding Atlantic Goliath Grouper in captivity was not possible until May of 2015.
- This fish species hosts multiple parasites on its gills, including dipletanid monogenean Pseudorhabdosynochus americanus, a type of flatworm common to various types of fish, including those of the Grouper family.
- Although one nickname for this fish is the jewfish, the American Fisheries Society stopped using the name in 2001 after receiving multiple complaints that the name was culturally insensitive. It’s unclear how these fish got the nickname.