Because their range exceeds national borders, the best approach to their conservation is regional closed seasons. Sampling of fish landed in the U.S. Virgin Islands and Puerto Rico during the 1970s and 1980s indicates that Nassau grouper were commonly caught, mostly from spawning aggregation sites.
Currently, Nassau grouper are occasionally reported during underwater reef surveys at low density. Coloration varies, but adult fish are generally light beige, with five dark brown vertical bars, a large black saddle blotch on top of the base of the tail, and a row of black spots below and behind each eye.
A dark band that forms a tuning-fork pattern on top of the head, beginning at the front of the upper jaw, extending through each eye, and then curving to meet its corresponding band in front of the dorsal fin. They can be distinguished from other groupers by the vertical bars and dark saddle coloring along the dorsal part of the area preceding the tail.
Color pattern can change within minutes from almost white too bicolored to uniformly dark brown, according to the behavioral state of the fish. They take advantage of lower light levels at dawn and dusk, combined with the higher number of prey during changeover between diurnal and nocturnal fishes.
Nassau grouper are found in tropical and subtropical waters of the western North Atlantic. This includes Bermuda, Florida, Bahamas, the Yucatán Peninsula, and throughout the Caribbean to southern Brazil.
There has been one verified report of Nassau grouper in the Gulf of Mexico at Flower Gardens Bank. The Nassau grouper is considered a reef fish, but it transitions as it grows through a series of shifts in both habitat and diet.
As juveniles, they are found in nearshore shallow waters in macro algal and seagrass habitats. The main influences on where they live are not known, though water clarity, habitat, and bent hos (the community of organisms in the seabed) seem to be important.
Nassau grouper tend to spend a lot of time in one spot, often on a high-relief coral reefs or rocks in clear water. Larger fish tend to occupy deeper reef areas with greater vertical relief.
While adult Nassau groupers can change sex after hormone injection, natural sex-change has not been confirmed. Sites have been found near the edges of reefs, as little as 50 yards from the shore, near drop-offs into deeper water across a wide range of depths (20 to 200 feet) and environments (including soft corals, sponges, stony coral outcrops, and sandy depressions).
Some more information on how Nassau grouper get to their spawning sites, based on limited observations: After 1 to 2 months of floating with the ocean currents, the larvae settle in nearshore shallow waters in macro algal and seagrass habitats.
Adults are relatively solitary, living in areas that (patchily) overlap other groupers’ home ranges. In some countries with protective regulations, there are too few enforcement officers to cover a large geographic area with many landing locations.
Meanwhile, fish caught during closed season are held and later marketed as legal capture. The Nassau grouper is a predatory fish that lives on the coral reefs of the Caribbean Sea and adjacent waters.
During the majority of the year, Nassau groupers are reddish brown in coloration, with vertical light bars along the head and body. They use their very large mouths to create enough negative pressure to suck in whole fishes or lobsters, and they swallow them quickly and efficiently.
Throughout its entire geographic range, there are less than 100 known spawning aggregation sites where Nassau grouper reproduce year after year, and historically these aggregations included hundreds, if not thousands, of individuals reproducing together for a few days before returning to their home reefs. Individual Nassau groupers are known to travel several dozen miles and further to form part of a spawning aggregation.
At the aggregation sites, these fish 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. The behavior of forming dense spawning aggregations, where all the individuals from several square miles meet in once place, makes them an easy target for fishers.
These fish utilize the same, few locations and same, few days for spawning every year, so their presence is quite predictable. While considered endangered, Nassau groupers are still fished in many places around the Caribbean, but scientists and conservationists have been successful in having them protected during their spawning season, in an effort to help this valuable and ecologically important species recover.
Scientific classification Kingdom: Animalia Phylum: Chordata Class: Actinopterygii Order: Performed Family: Serranidae Subfamily: Epinephrine Genus: Epimetheus Species: Binomial name Epimetheus stratus Synonyms Antics stratus Bloch, 1792 Serra nus stratus (Bloch, 1792) Antics China Bloch & Schneider, 1801 Sparks chrysomelanus Labeled, 1802 Serra nus gymnopareius Valentines, 1828 Superimposed on this base color are a number of lighter stripes, darker spots, bars, and patterns, including black spots below and behind the eye, and a forked stripe on the top of the head.
By the light of the full moon, huge numbers of the grouper cluster together to mate in mass spawning. The Nassau grouper is fished both commercially and for sport; it is less shy than other groupers, and is readily approached by scuba divers.
However, its numbers have been sharply reduced by overfishing in recent years, and it is a slow breeder. Furthermore, its historic spawning areas are easily targeted for fishing, which tends to remove the reproductively active members of the group.
The species is therefore highly vulnerable to overexploitation, and is recognized as critically endangered on the IUCN Red List. The governments of the United States, the Cayman Islands, and the Bahamas have banned or instituted closed fishing seasons for the Nassau grouper in recent years.
It has been identified as one of only two viable sites remaining for the species, of 9 originally known locations. However, the Nassaugrouper's spawning region is not included in this marine protected area (MPA).
Many conservation methods have been put in place to help the grouper, including closed seasons, when fishing is not allowed. Some areas are protected, a complete ban on fishing the grouper in US waters has been instituted.
However, analysis of declines in both populations and the size spawning aggregations has led to the species being uplifted to critically endangered by the IUCN Red List in 2018. The Nassau grouper has been depicted on postage stamps of Cuba (1965, 1975), the Bahamas (1971 5-cent), and Antigua and Barbuda (1987 40-c).
The Nassau grouper was placed on the World Conservation Union's realist of threatened species in 1996, and it was determined to be endangered because its population has declined by 60% in the past 30 years. Over a third of spawning aggregations have been estimated to have disappeared, and the grouper is considered to be commercially extinct in some areas.
The current population is estimated to be more than 10,000 mature individuals, but is thought to be decreasing. ^ Shcherbina, Andrey; Glen G. Gawarkiewicz; Christopher A. Liner; Simon R. Horror (Sep 2008).
“Mapping bathymetric and hydrographic features of Glover's Reef, Belize, with a REMUS autonomous underwater vehicle” (PDF). We are looking forward to sampling lots of fresh local seafood, but have heard that eating grouper can be dangerous.
Never heard of Grouper poisoning. Ther was an outbreak of Conch poisoning some years ago, whih was caused by the storage methods-the vendors kept the catch in the harbor, once they had fresh running water the problem was corrected. Toucan get poisoned by eating Barracuda which is considered to be a delicacy locally, but can be risky if it has not been handled or prepared properly.p.s most of the hotels buy imported seafood from the restaurant supply companies.
The grouper population throughout the northern Caribbean and Atlantic are dwindling rapidly. I have dove around New Providence often, and in the past decade, have witnessed the NassauGrouper population grow sparse.
So, the fishermen must catch the grouperyoueat farther out in the ocean, probably in deep waters. You may want to refrain from eating grouper until the populations are re-established through no-take zones and more controls on netting them during spawning aggregations.
I know it's hard not to order grouper ; I had a half plate at Nippers on Aback, and it literally melted in my mouth! Much different from the aging, frozen grouper eaten here in Ohio, even in plush restaurants.
As long as the grouper is fairly young (under 36 inches) and not one of those ancient Jewish, your risk is next to nothing. As Robert points out, grouper are becoming overfished, so big ones are even more scarce.
Once again, Robert and I are on the same wavelength as far as conservation goes. Thank you, Susan for your sensitivity to a serious worldwide problem re over-fishing. I carry the below list in my purse to consult to NOT eat the following fish: (They are in imminent danger of disappearing from our waters FOREVER! )Chilean Sea BassFlounderOrange RoughyAtlantic Halibut Snapper Pacific SalmonSwordfishA great substitution I have found for the above fish is a farmed fish called Tilapia.
It's plentiful, and a delicate white fish similar to Grouper and Chilean Sea Bass. It is found fresh and frozen in many of the better grocery chains. If you have a Ruby Tuesday's close by, they have a wonderful Tilapia Florentine that will give you a chance to try it.
Here in Tampa Bay Florida the old-time fisherman and their families are being shut out due to continually tightening bans on grouper fishing, and guess who is financing this ban? The people answering your question don't have any idea of the truth of the matter.
Upon serving the platter on those occasions it has been reported that fish bites have occurred in alarming numbers. In deference to the fishing industry, the demise of the grouper and efforts to bring back the species to high numbers again is based upon marine biology research...not the sport fishing industry.
Normally solitary and territorial, during the winter full moons they travel, sometimes over great distances, and group together to spawn. About fifty of these spawning aggregations sites have been recorded in different places throughout the Caribbean.
The Projects objectives were to observe the Nassau grouper (Epimetheus stratus) spawning aggregation off the western tip of Little Cayman, and to develop a protocol for monitoring their numbers and activity at the site. For two weeks, a team of divers that included five volunteers, staff from the Cayman Islands Department of Environment, and led by Reefs Field Operations Coordinator, Leslie Whale, visited the aggregation site and nearby reefs.
Grouper Moon Collaborators and Sponsors During the Grouper Moon Project, REEF worked in cooperation with the Cayman Islands Department of Environment, the Southern Cross Club, Sam McCoy Diving Lodge, and the Coral Reef Alliance. There was also generous support from Peter Hillenbrand, Island Air, the Little Cayman Beach Resort, and Paradise Villas.
There is no doubt that as the mysterious life of the grouper, through research studies is discovered, and critical regulations to keep its populations within healthy numbers are implemented, that long-term benefits to the fishing industry will occur. These regulations and no-take zones have benefited other species as well; the spiny lobster in northern Extra, Bahamas has rebounded in huge numbers in an area protected aggressively by game wardens by the Bahamian Govt.
Local Bahamians fish for spiny lobster around the periphery of the no-take zone, and catch GREAT numbers of them today, which disperse from the protected area. Tourists in Paradise Island, unknowingly, eat these plentiful lobsters taken from this high-population area.