More on author: Bloch. Short description Morphology Morphometrics Dorsal spines total : 11 - 12; Dorsal soft rays total : ; Anal spines : 3; Anal soft rays : 8. Caudal fin rounded in juveniles. Dorsal fin notched between forward spines; 3rd or 4th spine the longest. Bases of soft dorsal and anal fins covered with scales and thick skin; scales small and greatly overlapping. Ground color tawny in individuals in shallow water, shading to pinkish or red in those from deeper water, sometimes with an orange cast.
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These large, oblong fish can change both color and gender, and live at the rocky reef bottom of tropical Western Atlantic waters. They are usually a light buff to pink color with striking darker bars and spots, but can change to very light or very dark quickly.
There is some debate, but they are protogynous hermaphrodites, meaning most start out as females and then become males after a few years of spawning. They grow up to 4 feet long and eat mostly crustaceans and other smaller fish by opening their mouths and inhaling them. English language common names include Nassau grouper, day grouper, grouper, hamlet, rockfish, sweet lip, and white grouper.
Other language common names are cherna Spanish , cherna criolla Spanish , granik siodlasky Polish , jacob peper Dutch , jocupepu Papiamento , mero Spanish , mero gallina Spanish , merou raye French , nagul French , negue, tienne French , vieille French , yakupepu Papiamento. This fish is considered an important food fish throughout the Caribbean and in the West Indies.
Hook and line as well as traps are the main methods used to capture the Nassau grouper. The flesh is primarily marketed as fresh, however there have been reports of ciguatera poisoning from human consumption of this fish. Divers interact with unwary, curious groupers that are easy to feed. They are favorite subjects of underwater photographers due to their zebra-like coloration.
There have been reports of ciguatera poisoning from human consumption of Nassau groupers. Ciguatera poisoning is caused by dinoflagellates microalgae found on dead corals or macroalgae. By feeding on these corals and macroalgae, herbivorous fishes accumulate a toxin generated by these dinoflagellates. Largely a phenomenon of tropical marine environments, ciguitoxin accumulates still further in snappers and other large predatory reef species that feed on these herbivorous fishes.
If accumulated levels of the toxin are great enough they can cause poisoning in humans whom consume the flesh of these fishes. Poisoned people report having gastrointestinal problems for up to several days, and a general weakness in their arms and legs. It is very rare to be afflicted with ciguatera poisoning.
Currently all harvest of the Nassau grouper is prohibited in the U. It is also listed as a candidate for the U. Endangered Species List. The Nassau grouper has been heavily fished and vulnerable to overfishing. The spawning aggregations that appear at the same site each year are easy targets for fishers.
During these spawning events, the reproductively mature fish are often caught. This further limits potential population growth through the removal of mature females, leaving behind the young females that release fewer eggs for fertilization. The IUCN is a global union of states, governmental agencies, and non-governmental organizations in a partnership that assesses the conservation status of species.
This grouper is common on offshore rocky bottoms and coral reefs throughout the Caribbean region. They occur at a depth range extending to at least feet 90 m , preferring to rest near or close to the bottom.
Juveniles are found closer to shore in seagrass beds that offer a suitable nursery habitat. Nassau groupers are typically solitary and diurnal, however, they may occasionally form schools. When threatened by predators, this fish can camouflage itself, blending in with the surrounding rocks and corals.
Groupers are frequent visitors to wrasse cleaning stations. The grouper will open its mouth in a non-threatening manner, attracting cleaner fish to enter its mouth to remove parasites.
Distinctive Features The Nassau grouper is an oblong, large fish with large eyes and coarse, spiny fins. The third or fourth spine of the dorsal fin is longer than the second spine. Pelvic fins are shorter than the pectoral fins, with the insertion point located below or behind the ventral terminus of the pectoral fin base.
The bases of the soft dorsal and anal fins are covered with scales and skin. Caudal fin is rounded in juveniles, convex in adults. Coloration This grouper has a light, buff background color in shallow water individuals, pinkish to red in those from deeper water. There are five irregular dark brown vertical bars on each side and a large black saddle on the top of the caudal peduncle.
The third and fourth vertical bars form a W-shape above the lateral line. A tuning fork-shaped mark is located on the forehead. Another dark band travels from the snout through the eye, curving up to meet the same band from the other side, just before the dorsal fin origin. Black dots are located around the eyes. This is some variation among individuals, as some fish may have irregular pale spots on the head and body. The Nassau grouper can change color pattern from light to dark brown very quickly, depending upon the surrounding environment and mood of the fish.
Another color pattern is observed in the Nassau grouper when two adults or an adult and large juvenile meet. The smaller individual displays a bicolored pattern, with a dark head and white fins, caudal peduncle, and ventral body. There is a white band that reaches from the snout, past the eye towards the dorsal fin.
After swimming away, the bicolored fish resumes its normal barred pattern within minutes. This same bicolored pattern is observed in aggregations of spawning fishes, perhaps indicating a peaceful, non-territorial state. Dentition Groupers have several sets of strong, slender teeth that act as raspers. These teeth are not used to tear flesh as with the barracudas and sharks, but rather to prevent small fish from escaping. Size, Age, and Growth Growing to a maximum of 4 feet 1.
More commonly, this grouper reaches a length of feet. The maximum age reported for this fish is 16 years. Food Habits As a carnivorous predator, the Nassau grouper has a diet that consists mainly of fish, shrimps, crabs, lobsters, and octopuses. Prey fish include parrotfishes, wrasses, damselfishes, squirrelfishes, snappers, and grunts. This clever fish patiently waits in hiding, utilizing its ability to camouflage, until it pounces on its prey.
By opening its mouth and dilating the gill covers to draw water in, groupers generally engulf their prey hole in one quick motion. An interesting note, as a friendly, unwary fish, if offered food by divers it will repeatedly return searching for more food handouts. Reproduction The Nassau grouper forms large spawning aggregations from a few dozen to over , individuals. These aggregations form in depth of ft m on the outer shelf near the full moon during the winter months.
During the spawning event, most fish display the bicolored pattern and swim near the bottom. Some females remain in the barred color pattern and become very dark as mating approaches. A group of bicolored males swims in circles near the female upon sunset.
Courtship behavior includes vertical spirals, short vertical runs followed by crowding together and rapid dispersal, and horizontal runs near the bottom. Release of gametes is initiated by the female moving in a rapid forward and upward direction. The eggs are released by the female, followed by the release of sperm by all the following bicolored males as well as further release of eggs by some bicolored females.
Fertilization occurs by chance in the open waters, large spawning aggregations further improve these chances. One such aggregation was reported in the Bahamas which included as many as , fish. Groupers are protogynous hermaphrodites. After spawning as a female for one or more years, the grouper changes sex, functioning as a male during future spawning events.
Individuals of the Nassau grouper have been discovered to be male without previously going through a female stage and are smaller than the secondary males. It is believed by some that the sex change is triggered when the fish aggregate in preparation for spawning.
It is difficult to distinguish different species of grouper larvae from one another, since what information is known about egg and larval development is general. The eggs hatch into pelagic larvae that drift along with the currents for a month or so, prior to becoming juveniles. The larvae are characterized by kite-shaped bodies and elongated second dorsal spines. Juveniles settle at lengths of approximately 32mm, residing in vegetated areas near coral clumps.
At mm in length, the juvenile Nassau groupers move out from vegetated areas to surrounding patch reefs. Predators Predators of the Nassau grouper include large fish such as barracuda Sphyraena barracuda , king mackerel Scomberomorus cavalla , moray eels Gymnothorax spp. The sandbar shark Carcharhinus plumbeus and the great hammerhead shark Sphyrna mokarran are also known to feed on groupers.
Parasites Nassau groupers are host to a variety of parasitic organisms including isopods located in the nostrils, larval tapeworms in the viscera, and nematodes in the ovaries. These nematodes can have negative impact on the numbers of eggs produced by female Nassau groupers. The impact of these parasites on the health of the host is relatively unknown.
At these stations, gobies and shrimps remove isopods from the bodies, fins, mouths, and gills of these groupers and other fish. The genus name comes from the Greek Epinephelus meaning clouded over while striatus is Latin, referring to the striped color pattern. Synonyms include Anthias cherna Bloch and Schneider , Sparus chrysomelas Lacepede , and Serranus gymnopareius Valenciennes More Info.
Discover Fishes Epinephelus striatus. Nassau Grouper Nassau Grouper. Order: Perciformes Family: Serranidae Genus: Epinephelus Species: striatus Common Names English language common names include Nassau grouper, day grouper, grouper, hamlet, rockfish, sweet lip, and white grouper.
Importance to Humans Diver with Nassau grouper. Danger to Humans There have been reports of ciguatera poisoning from human consumption of Nassau groupers.
Conservation Status Nassau grouper up-close. Geographical Distribution World distribution map for the Nassau grouper The Nassau grouper is found throughout the tropical western Atlantic Ocean, including Bermuda, Florida, Bahamas, and throughout the Caribbean Sea, south to Brazil. Habitat This grouper is common on offshore rocky bottoms and coral reefs throughout the Caribbean region. Biology Nassau grouper residing among the corals. Coloration of the Nassau grouper blends in with its physical environment.
Indian River Lagoon Species Inventory
Advanced Search. Overall body color of Epinephelus striatus varies from tawny to pinkish red, with five dark vertical bars. The third and fourth bars branch above the lateral line and form a "W". Although Nassau and red grouper are similar in overall appearance, Nassau grouper possesses a black saddle on top of the caudal peduncle, black spots around the eye and a distinctive tuning-fork shaped marking on top of the head.
To address patterns of genetic connectivity in a mass-aggregating marine fish, we analyzed genetic variation in mitochondrial DNA mtDNA , microsatellites, and single nucleotide polymorphisms SNPs for Nassau grouper Epinephelus striatus. We expected Nassau grouper to exhibit genetic differentiation among its subpopulations due to its reproductive behavior and retentive oceanographic conditions experienced across the Caribbean basin. All samples were genotyped for two mitochondrial markers and 9 microsatellite loci, and a subset of samples were genotyped for 4, SNPs. Genetically isolated regions identified in our work mirror those seen for other invertebrate and fish species in the Caribbean basin.