Nassau Grouper becomes Critically Endangered

By BBN Staff: The Nassau grouper—a fish known for its spectacular spawning aggregations in and around the Caribbean Sea—is now a “Critically Endangered” species, according to a new assessment by the International Union for Conservation of Nature (IUCN).

The Nassau grouper (Epinephelus striatus) inhabits the waters of the Bahamas and the Caribbean, and averages about 20 pounds in weight.

Once a common species throughout its range, the fish has been in steep decline since 1980 and has declined by more than 80 percent over that time.

The Nassau grouper is now at risk of extinction, according to scientists.

“The uplisting of the Nassau grouper to Critically Endangered status is a renewed call to action following the implementation of 10 years of regulations through size limits, closed seasons and closed areas in Belize which has yet to provide adequate protection for this beleaguered species,” said Dr. Alexander Tewfik, Senior Conservation Scientist for the Wildlife Conservation Society’s Belize Program.

The Wildlife Conservation Society (WCS) conducted surveys in Belize that assisted in justifying the up lifting of the species.

The WCS notes that one of the biggest threats to the Nassau grouper is overfishing.

Heavy fishing conducted during the grouper’s enormous spawning aggregations, which occur over underwater promontories just after the full moons in December through March, is especially harmful to this species, by removing the biggest and best adults from the population.

The loss of pristine coral reefs—the grouper’s primary habitat—is also a contributing factor to the downward population trend of Nassau groupers.

The new assessment on the Nassau grouper and its new Critically Endangered listing was recently published and supported by studies and data generated by WCS scientists working in the coastal waters of Belize.

WCS is part of the Belize Spawning Aggregation Working Group, a partnership consisting of conservation NGOs, fisher groups, academic organizations, and the Belize Fisheries Department that have worked since 2001 to protect and manage the country’s fish aggregations in sites where they occur in Belize waters.

Thirteen of Belize’s Nassau grouper aggregation sites are fully-protected, and fishing for the species is closed for four months.

Further, only fish between 20 and 30 inches in size are legal for harvesting.

Nevertheless, some sites have seen fewer fish over the years.

At Glover’s Reef Atoll, a key WCS conservation area, one of the last viable aggregations of Nassau grouper totaled only 925 individual fish in 2018, down from more than 3,000 fish just five years prior and historic highs of 15,000 in the 1970s.

Physical evidence of fishing out of season on protected spawning aggregation sites includes hooked fish, anchors, and lights to attract fish to hooks.

“Our most recent findings on the Nassau grouper and its decline in key aggregation sites, along with the new designation as a Critically Endangered species, indicate that this fish is in need of a national conservation plan in Belize and in other countries where these groupers exist,” said Nicole Auil Gomez, Director of WCS’s Belize Program.

WCS reiterates that threatened fish needs a national plan to save species in Belize’s waters.

WCS’s work in Belize is generously supported by the Oak Foundation, The Summit Foundation, Oceans 5, and the UK’s Government’s Darwin Initiative.