This article will discuss some of the biggest Goliath Groupers ever caught. First we will discuss the 2 types of Goliath Groupers. Lastly we discuss some FAQ you might have about Goliath Groupers.
The goliath grouper (Epinephelus itajara) is one of the biggest bony fish you can expect to find swimming on the coral reef.
Fully grown, they’re huge fish, and the biggest goliath grouper ever caught weighed an impressive 308.44 kg (680 lb).
We’re going to take an in-depth look at this giant, generally solitary fish and discover that the common name is actually given to two very similar yet genetically different species.
We’ll review the records of the most enormous groupers ever caught and answer some frequently asked questions.
Before you grab your rod and head to the ocean to try and break the record, make sure you review the information about the laws relating to catching goliath groupers.
You’ll find in many areas that it’s either completely illegal to catch this giant fish or very carefully regulated, and permits are required.
How Big Is a Full-Grown Goliath Grouper?
A full-grown goliath grouper can reach 2.5 m (8.2 ft) in length and weigh at least 300 kg (660 lb).
However, to correctly answer how big do groupers get, we need to start by checking precisely what fish species we’re talking about.
The problem with using a common name, like goliath grouper, is that it can refer to several fish species found in different locations worldwide.
In this case, it’s actually pretty straightforward as the two fish that share the common name are quite similar.
The fish most frequently called the goliath grouper is the Atlantic goliath grouper.
However, there’s also another giant grouper, the Pacific goliath grouper.
So, let’s start by learning a little about both of these fish and answer how big goliath groupers are.
Atlantic Goliath Grouper (Epinephelus itajara)
The Atlantic goliath grouper occurs on the eastern Atlantic ocean coast of the Americas from northeastern Florida in the United States down to southern Brazil.
They can also be seen on the west coast of Africa, from Senegal to Angola.
To blend in amongst the coral rock or muddy bottom, the Atlantic grouper ranges from gray, brownish yellow, and greenish in color, and there are small black spots across its elongated body and rounded fins.
Smaller specimens often have three or four vertical bars on their sides that grow fainter before disappearing altogether once they reach about 1 m (3.3 ft) in length.
The fish is quite distinctive, with a broad, flat head and small eyes, and is naturally found on rocky natural reefs.
They also enjoy making their home on shallow artificial reefs, shipwrecks or amongst the submerged structures of oil and gas platforms.
Wherever it’s seen, this grouper tends to stay in shallower in-shore waters ranging from close to the surface to a maximum of about 100 m (328 ft) deep.
The generally solitary fish doesn’t stray far from its favored refuge, so they’re usually close to caves or rock ledges.
Atlantic goliath groupers are one of the biggest bony fish species in the ocean, and they’re the largest grouper found in the western Atlantic.
As we’ve already mentioned, the Atlantic coast species is the fish that’s most commonly called the goliath grouper. However, other locally used names include the jewfish, black bass, giant seabass, and giant hamlet.
Atlantic goliath groupers hunt smaller, slow-moving large fish and crustaceans, including calico crabs, shrimps, spiny lobsters, and other invertebrate species.
Like most groupers, they are ambush opportunistic predators and will rapidly open their large jaws to seize their prey, much of which is then swallowed whole.
The Atlantic goliath grouper is rated as being vulnerable with a population that’s said to be decreasing worldwide.
Pacific Goliath Grouper (Epinephelus quinquefasciatus)
Until quite recently, scientists generally thought that the giant grouper found in the tropical eastern Pacific Ocean from northern Mexico to the coast of southern Peru that locals had given the goliath name was the same fish as that found in the Atlantic.
However, it is now known that the Pacific goliath is a separate, albeit closely related, species.
Fortunately for us, the Pacific fish, known in Mexico as mero gigante, shares the same vital characteristics as its Atlantic sibling, including its maximum size.
In fact, without resorting to DNA testing, the two fish look identical side by side.
There haven’t been extensive studies on the populations of this fish, so it is classed as having a data-deficient status.
However, it is considered that populations are decreasing and could become vulnerable due to overfishing and environmental pressures.
What Is the Biggest Grouper Ever Caught?
The biggest grouper ever caught was an Atlantic goliath grouper weighing 308.44 kg (680 lb).
It was caught on the 20th of May, 1961, by Lynn Joiner from the Ice Dock on the Amelia River at Fernandina Beach, Florida, USA.
Spanish mackerel was used as bait, and it took 1 hour and 15 minutes to reel the fish in.
This colossal fish holds The International Game Fish Association record as the world record goliath grouper.
The 1961 Florida record catch dwarfs the next IGFA recognized heaviest goliath grouper ever caught, which weighed “just” 206.61 kg (455 lb) when it was landed off Marco Island, Florida, in May 1981 by angler Harry Hays.
A giant goliath grouper believed to weigh 264 kg (583 lb) was reported as caught in May 2020 on a deep-sea fishing trip by 16-year-old angler Reegan Werner.
The regulations in place at the time intended to protect this fish from being caught or removed from the water meant that it wasn’t recorded as a record.
The 9 Biggest Grouper Catches
Although the goliath grouper is by far the biggest, other grouper catches have also reached impressive sizes. Here are some other IGFA record grouper catches.
Warsaw Grouper (Epinephelus nigritus) – 198.10 kg (436 lb 12 oz)
Location – Gulf of Mexico, Florida, USA
Date – 22nd December 1985
Caught by – Steve Haeusler
Giant Grouper (Epinephelus lanceolatus) – 179.50 kg (395 lb 11 oz)
Location – Latham Island, Tanzania
Date – 10th March 2004
Caught by – Shayne Keith Nelson
Convict Grouper (mahata) (Epinephelus septemfasciatus) – 120.00 kg (264 lb 8 oz)
Location – Yonaguni Island, Okinawa, Japan
Date – 25th April 2011
Caught by – Koji Yoshida
Potato Grouper (Epinephelus tukula) – 77.85 kg (171 lb 10 oz)
Location – Miyako Island, Okinawa, Japan
Date – 4th June 2011
Caught by – Takayuki Shibayama
Black Grouper (Mycteroperca bonaci) – 56.24 kg (124 lb 0 oz)
Location – Gulf of Mexico, Texas, USA
Date – 11th January 2003
Caught by – Tim Oestreich, II
Mustache Grouper (Epinephelus chabaudi) – 55.00 kg (121 lb 4 oz)
Location – Desroches Island, Seychelles
Date – 1st January 1998
Caught by – Charles-Antoine Roucayrol
Gulf Grouper (Mycteroperca jordani) – 51.40 kg (113 lb 5 oz)
The record for gulf grouper is recorded as a tie by the IGFA as a catch in 2021 only narrowly beat the existing record.
51.40 kg (113 lb 5 oz)
Location – Gonzaga Bay, Mexico
Date – 24th October 2021
Caught by – Gary Puls
51.25 kg (113 lb 0 oz)
Location – Loreto, Baja California Sur, Mexico
Date – 25th April 2000
Caught by – William Klaser
Mottled Grouper (Mycteroperca rubra) – 49.70 kg (109 lb 9 oz)
Location – East Side, Gibraltar
Date – 13th April 1996
Caught by – Albert Peralta
Broomtail Grouper (Mycteroperca xenarcha) – 49.24 kg (108 lb 9 oz)
Location – Cedros Island, Baja, Mexico
Date – 16th June 2016
Caught by – Jeff Mariani
Why Are Goliath Groupers So Big?
Goliath groupers are so big because they’ve evolved to be more or less the top of their food chain, and you don’t get there by being tiny!
Adult goliath groupers don’t have predators other than humans or large sharks to fear, and they have historically had abundant food.
Because they don’t have much competition, they have their pick of nutritious food, which allows them to grow to such impressive sizes.
Are Goliath Groupers Protected?
Yes, thankfully, because of their vulnerable status, both the Pacific and Atlantic goliath groupers are protected from harvest almost everywhere they are found.
Goliath groupers are known to be slow growers and take at least six years to reach sexual maturity.
In addition, they have a low reproductive rate, so their adult populations are easily affected by overfishing and environmental changes to their spawning grounds.
Marine scientists believe that the historical population of Atlantic goliath groupers has been reduced globally by at least 80% thanks to human activities.
In the United States territorial waters, catching goliath groupers were banned in 1990 to allow the population to recover.
The Atlantic goliath grouper was considered a candidate for the Endangered Species Act. Authorities made similar rules in the Caribbean sea in 1993.
However, while deliberately catching and killing the fish is still banned in almost all areas, the Florida Fish and Wildlife Conservation Commission launched a controlled harvest program in 2022, believing that populations had recovered sufficiently.
The goliath harvest program allows 200 permits to be issued yearly for one fish per person during the open season of March 1st – May 31st.
Rules specify that anglers must immediately release groupers caught accidentally outside of the harvest program unharmed.
Specifically, a large goliath grouper should never be removed from the water for photography or weighing.
Their skeletons cannot support their vast weight out of the water, and the fish almost always suffer fatal injuries even if they are returned to the water.
Goliath Grouper FAQs
How Much Are Goliath Groupers Worth?
Many people believe that goliath groupers are worth far more alive than they are dead.
Scuba diving and other ecotourism activities that enjoy seeing impressive fish can bring in millions of dollars annually.
The famous marine biologist Sylvia Earle said, “killing Goliath groupers will also kill growing economic benefits derived from divers who revel in the opportunity to be in the presence of these iconic animals.”
The cost of the Florida permit system means that a legally caught Atlantic ocean goliath grouper will be unrealistically expensive to capture for use as a food fish.
An estimate from 2021 suggests that the fish would cost at least $40 per pound, making it uneconomic compared to other groupers.
What Hunts Goliath Groupers?
Apart from humans, an adult goliath grouper only has large sharks, including the great hammerhead sharks (Sphyrna mokarran) and the sandbar shark (Carcharhinus plumbeus), to worry about as natural predators.
As the smaller young goliath groupers grow, they will need to avoid other groupers, barracuda, king mackerel, and moray eels which would all enjoy them for a meal.
Can You Eat Goliath Groupers?
Historically, a juvenile goliath grouper was regarded as a fish with excellent flesh for eating that tasted similar to seabass and halibut.
It is said that the older the fish gets, the tougher its meat becomes and the more cooking and tenderizing it needs.
However, a modern goliath grouper can contain high concentrations of toxic mercury in its body which can present serious human health risks.
The man-made contaminant can cause renal, immune, digestive, cardiovascular, neurological, and reproductive damage, including erectile dysfunction.
So, all in all, this is probably a fish best left in the Atlantic ocean rather than featured on your plate.
Do Goliath Groupers Make a Noise Underwater?
The goliath grouper can make a loud, low-frequency sound using its swim bladder when it feels threatened.
Sometimes this is called an underwater sonic-boom, and it’s often heard by scuba divers when they get close to the fish.
It’s been suggested that listening out for the grouper’s noise could be used to detect underwater vehicles in sensitive military areas.
The goliath grouper has even been included in the DARPA Persistent Aquatic Living Sensors program that studies using animals as natural warning devices.
Are Atlantic Ocean Goliath Groupers Dangerous?
A large goliath grouper could be dangerous to scuba divers. It’s not that the fish is aggressive, but it is large and cumbersome if you happen to be in its way.
Huge goliath groupers have been seen stalking divers underwater and have even attempted to hunt and herd them for an ambush attack actively. This isn’t a fish known for its high level of intelligence!
In reality, there isn’t any risk of being eaten by a goliath grouper. More likely is an injury caused by being rushed by a fish that feels cornered or receiving a blow from an aggressive tail maneuver.
Is the Goliath Grouper the Biggest Fish?
The goliath grouper is one of the biggest bony fish (Osteichthyes) and the largest species of grouper, but they’re far from the biggest fish in the ocean.
The biggest fish of all is the whale shark (Rhincodon typus), which can reach 18.8 m (61.7 ft).
As far as bony fish go, the biggest is the ocean sunfish (Mola mola) which has been recorded to measure 4.3 m (14 ft) from fin to fin and weighs 2,300 kg (5,100 lb).
The longest bony fish is the giant oarfish (Regalecus glesne), and the largest ever found measured 13.7 m (45 ft) in length.
A full-grown goliath grouper could measure as much as 2.5 m (8.2 ft) in length and the biggest goliath grouper ever caught weighed a massive 308.44 kg (680 lb).
Due to their highly vulnerable population, the goliath grouper is protected from capture almost everywhere in the world.
Even if they weren’t, the high levels of man-made mercury pollution that are sadly found in goliath grouper species flesh means that this is a fish that definitely shouldn’t be on your menu!
British-born Dan has been a scuba instructor and guide in Egypt's Red Sea since 2010.
Dan loves inspiring safe, fun, and environmentally responsible diving and particularly enjoys the opportunity to dive with sharks or investigate local shipwrecks.
When not spending time underwater, Dan can usually be found biking and hiking in Sharm's desert surroundings.