Some more information on how Nassau grouper get to their spawning sites, based on limited observations: 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 of them travel only a few kilometers others are known to travel up to several hundred kilometers to the aggregation site. The timing and synchronization of spawning may be to accommodate widely dispersed adults, facilitate egg dispersal, or reduce predation on adults or eggs.Īs spawning time approaches, adults move from the reefs where they live to specific spawning areas. They form from November through February around the full moon, when water temperatures are around 79☏. All of their known reproductive activity happens in these aggregations. Nassau grouper spawn in aggregations-gatherings of hundreds, thousands, or tens of thousands. While adult Nassau groupers can change sex after hormone injection, natural sex-change has not been confirmed. Nassau grouper pass through a juvenile bisexual phase, then mature directly as males or females. Most reach sexual maturity when they are around 20 inches long and about 4 to 5 years old. Males and females typically mature when they reach about 15 to 17 inches. World map providing approximate representation of the Nassau grouper's range Lifespan & Reproduction However, sampling along shoreline habitats of the Florida Keys-where smaller juveniles might be expected-has been limited to date. No larval Nassau grouper or juveniles smaller than 20 inches in length have been collected or observed in Florida waters. ![]() Nassau grouper are mostly absent from the continental United States-except Florida, where larger juveniles and adults have been recorded. Both adults and juveniles will use either natural or artificial reefs. Larger fish tend to occupy deeper reef areas with greater vertical relief. Nassau grouper tend to spend a lot of time in one spot, often on a high-relief coral reefs or rocks in clear water. Their depth range may be influenced more by the availability of suitable habitat than by food resources, since their diet is highly varied and has more to do with body size than of water depth. The main influences on where they live are not known, though water clarity, habitat, and benthos (the community of organisms in the seabed) seem to be important. They shift deeper as they grow, to predominantly reef habitat (forereef and reef crest). As juveniles they are found in nearshore shallow waters in macroalgal and seagrass habitats. The Nassau grouper is considered a reef fish, but it transitions as it grows through a series of shifts in both habitat and diet. ![]() They generally live among shallow reefs, but can be found in depths to 426 feet. There has been one verified report of Nassau grouper in the Gulf of Mexico at Flower Gardens Bank. Virgin Islands, Puerto Rico, Bermuda, the Bahamas, the Greater Antilles, the Lesser Antilles, and central America. Nassau grouper are found in tropical and subtropical waters in the Caribbean and western North Atlantic, including south Florida, U.S. Our scientists use a variety of innovative techniques to study and protect this species. NOAA Fisheries is dedicated to the conservation of Nassau grouper. Nassau grouper is listed as threatened under the Endangered Species Act. Because their range exceeds national borders, the best approach to their conservation is regional closed seasons. Currently, all harvest of Nassau grouper is prohibited in the United States. ![]() In some cases, Nassau grouper is commercially extinct through much of its geographical range. It was easy for commercial and recreational fisherman to catch Nassau grouper and it soon became scarce. Nassau grouper used to be one of the most common species of grouper in the United States. ![]() They are late-maturing, long-lived, top-level predators found in tropical and subtropical waters in the Caribbean and western North Atlantic. These large fish are associated with hard structures like reefs (both natural and artificial), rocks, and ledges. It is a member of the family Serranidae, which includes groupers valued as a major fishery resource such as the gag grouper and the red grouper.
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