Spawning Aggregations

Nassau grouper is internationally recognized as an endangered species. PHOTO CREDIT: Tim Higgs.

In 2008, The Bahamas took the initiative to protect our population of Nassau grouper by implementing a closed season during the winter months when grouper are reproducing. Nassau grouper is a very popular commercial fish, and is the second most reported fish caught in The Bahamas after snapper! Unofficial statistics for 2010 put Nassau grouper landings somewhere around 295,000 pounds for the whole country. Nassau grouper is culturally important to Bahamians as it features in many of our local dishes and has become somewhat of an icon. The closed season has been widely promoted and many people are following the rules. Some fishermen claim to have seen an improvement in Nassau grouper populations in recent years. Nassau grouper flourish in The Exuma Cays Land and Sea Park, where fishing pressure has been reduced for the last 25 years; past studies have shown that 74% of Nassau grouper found in northern Exuma originated from the park. This shows that conservation initiatives can work for the population. There are still some people, however, who choose to eat and fish for Nassau grouper when the season is closed, taking advantage of large spawning aggregations to catch a lot of fish in a short amount of time.

Step out to the big picture. Nassau grouper is internationally recognized as an endangered species; it is officially listed on the IUCN’s Red List of Endangered Species along with other well known animals such as the giant panda, blue whale and whooping crane. According to NOAA (the United States National Oceanic and Atmospheric Administration), fishing for Nassau grouper is now prohibited by the Fishery Management Councils of The Caribbean, South Atlantic, Gulf of Mexico and Florida. NOAA considers Nassau grouper to be overfished in The Caribbean, so we are very lucky in The Bahamas to still be able to fish for them. Our luck, no doubt in part to the fact that the population of The Bahamas remains relatively small compared the area of our marine environment. We should take a lesson from our Caribbean neighbours and do what we can now to prevent loss of marine resources in the future.

So why the closed season? During the winter full moons, typically December – March, Nassau grouper migrate (some over 100 miles!) to meet with other Nassau grouper in large spawning aggregations, to increase their chances of reproducing and passing on their genes. Fish gather together in densities greater than normal (varies by species) and release eggs and sperm into the water column so that the eggs may be fertilized, and then transported by currents to other locations. Spawning aggregations may include thousands of fish and they occur repeatedly in the same locations at predictable times, so this makes them an easy target for fishing. However, because grouper travel so far to join a spawning aggregation (SPAG), fishing out a SPAG can have far-reaching effects. Nassau grouper is an important predator on our coral reefs and help to keep our marine ecosystems balanced and healthy. What many people may not realize, however, is that Nassau grouper is not the only fish in The Bahamas that reproduces in SPAGs. Black grouper, mutton snapper, Cubera snapper, and red hind are some of the others. So when you make your choice on what to have for dinner, it is great to follow the seasons and exclude Nassau grouper from your diet (this year from December 1st – February 29th), but also consider these other fish that do not currently have legislation protecting their reproduction.

For more information, visit www.friendsoftheenvironment.org or contact FRIENDS at (242) 367-2721.

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