Overfishing, not goliath groupers, causes declines in Florida lobster and snapper stocks.

Study finds critically endangered goliath groupers are not to blame for declining lobster and snapper stocks in Florida.

Fort Pierce, Florida, October 12, 2012

Media Contact: Dr. Sarah Frias-Torres


Independent scientist, Dr. Sarah Frias-Torres announced today the first comprehensive study on whether culling the protected goliath grouper population in Florida to increase lobster and fish stocks is supported by scientific evidence.

Goliath Grouper meets Dr. Sarah Frias-Torres. Photo Credit: Dr. Mark Eakin

Goliath grouper, Epinephelus itajara, is listed as critically endangered by the IUCN (International Union for the Conservation of Nature). The largest grouper fish in the Atlantic ocean, goliaths can reach 8 feet (2.5 meters) in length, weigh 1,000 pounds and live more than 40 years. After being fished to near extinction, goliaths have been protected by a moratorium on harvest in U.S. federal and state waters since 1990 and in the U.S. Caribbean since 1993. Elsewhere in the Atlantic ocean, the species is either extinct, or critically endangered.

Over the last decade, Florida recreational and commercial fishermen have demanded a “thinning out” of the population, as fishers consider goliath groupers a major predator of spiny lobster, snapper and other grouper species, and the main reason for declines in such target species.

The study titled “Should the Critically Endangered Goliath grouper Epinephelus itajara be culled in Florida”, analyzed fisheries landing data since the 1950s, diver based surveys and published dietary studies. It concludes that :

1) Goliath groupers eat invertebrates (worms, molluscs and crustaceans) and poisonous fish, not snappers and other groupers. Surprisingly, many of the prey consumed by goliath groupers are in turn predators of juvenile spiny lobster. Hence, goliath groupers are a fishers’ best friend, because through top-down predator control, goliaths could allow more juvenile lobsters to grow and become available to fishers.

2) The slow recovery of the goliath grouper population in Florida is not the cause for declining lobster and snapper stocks in Florida. Instead, overfishing is the main cause.

3) A thriving goliath grouper population could provide additional socio-economic benefits in ecotourism, and as a potential biocontrol agent for the invasive lionfish.

“Goliath groupers are a national treasure. Florida is the only place in the world where we can encounter these gentle giants, from juveniles to adults. Florida also contains 99 % of the spawning aggregation sites known worldwide. With this study in hand, we now have a strong argument to continue protection of the goliath grouper and dismiss any claims that the goliaths are destroying valuable stocks of lobster, snapper and other groupers.” Said Dr. Sarah Frias-Torres, the author of this study.

The research, published today at the journal Oryx, was funded by the Schmidt Ocean Institute, and conducted when the author was a postdoctoral fellow at the Fort Pierce-based Ocean Research & Conservation Association (ORCA). Currently Dr. Frias-Torres is a research collaborator with the Smithsonian National Museum of Natural History in Washington DC and the Smithsonian Marine Station in Fort Pierce, Florida.

Oryx, the International Journal of Conservation, publishes research on biodiversity conservation, conservation policy and sustainable use, and the interactions of these matters with social, economic and political issues.

The full scientific article can be downloaded for free at the Oryx journal web site

Frias-Torres, S. (2013). Should the critically endangered Goliath grouper, Epinephelus itajara, be culled in Florida? Oryx Volume 47, Issue 1, pp 88-95.