Tropical to temperate latitudes in the Atlantic Ocean
Coral reefs and other hard bottoms as well as mangrove forests
Critically Endangered (Very Highly Vulnerable To Extinction)
Order Perciformes (perch-like fishes), Family Epinephelidae (groupers and relatives)
It is easy to see where the Atlantic goliath grouper gets its name. Reaching lengths of at least 8 feet (2.5 m) and weights up to 700 pounds (320 kg), this species is one of the largest predators on coral reefs and along mangrove forests in the Atlantic Ocean and one of the largest groupers in the world.
The Atlantic goliath grouper, like most groupers, is an ambush predator and eats fairly large fishes and invertebrates and even small sharks. Reefs with large numbers of predators, like Atlantic goliath groupers, are known to be healthier than reefs with no predators, so this species may represent an important part of the reef food web. Atlantic goliath groupers feed by swallowing their prey whole; they do not chew. They use their very large mouths to create enough negative pressure to suck in whole fishes or large invertebrates, and they swallow them quickly and efficiently.
Throughout most of the year, low numbers of Atlantic goliath groupers are observed in any one place. They are at the top of their food web and are therefore naturally rare. However, during reproduction (immediately after the full moons between June and December), they come together in groups of at least 100 individuals. These groups are known as spawning aggregations, and they form at relatively few places throughout the species’ range. Individual Atlantic goliath grouper likely travel many miles to reach their preferred spawning sites and form part of the spawning aggregation. At these sites, the groupers reproduce by a method known as broadcast spawning, where females release eggs and several males release sperm into the water column above deep reefs all at the same time. This method increases the likelihood that eggs will become successfully fertilized and that fertilized eggs will not be eaten by egg predators on the reef surface.
Though they were likely naturally rare, scientists believe that destructive fishing practices have reduced the numbers of Atlantic goliath groupers by at least 80% and that the species is now critically endangered. In other words, it is very highly vulnerable to extinction. These fish utilize the same, few locations and same, few days for spawning every year, so their presence is quite predictable. Furthermore, a total lack of fear of people makes them an easy target for spear fishers. Finally, the Atlantic goliath grouper’s large size, slow growth, and ease of capture all contribute to slow its recovery, even where laws have been put in place to give it some or complete legal protection from fishing (e.g., in the USA and Brazil). It is important to continue to monitor Atlantic goliath grouper population trends in order to determine whether or not the species is recovering or if stronger legal protection may be required.
A note on a closely related species: the Atlantic goliath grouper lives on both sides of the Atlantic Ocean – in the Caribbean Sea and adjacent waters and off the west coast of Africa. A closely related species, the Pacific Goliath Grouper, is restricted to the eastern tropical Pacific Ocean from Mexico to Peru. Scientists only recently divided the species into two, based on their slightly different genetic makeup. The two species are similar in both appearance and behavior, but little is known about the population trends or conservation status of the Pacific goliath grouper.
Oceana joined forces with Sailors for the Sea, an ocean conservation organization dedicated to educating and engaging the world’s boating community. Sailors for the Sea developed the KELP (Kids Environmental Lesson Plans) program to create the next generation of ocean stewards. Click here or below to download hands-on marine science activities for kids.