Marine Species on the Line
In The Bahamas, money and fish go hand in hand, and so says the cash itself: The country’s penny is ornamented with a starfish, the dime a bonefish, and the $100 bill a jumping blue marlin. More than 20,000 Bahamians make their living fully or partly from fishing, and fishing exports earned the country $62.7 million in 1997. The bulk of that sum is brought in by three species: the Nassau grouper, the queen conch, and the Caribbean spiny lobster. The three are overfished elsewhere in the Caribbean but are maintaining a foothold—albeit a shaky one—in The Bahamas.
The Exuma Cays Land and Sea Park, a 456 square kilometer area of protected ocean in the center of archipelago, was established in 1959 in part to help preserve and revive fisheries for these species. Several biological surveys of the park show that the plan is working: Densities of each of “the big three” are significantly higher, and body sizes are larger, inside the park than out. What’s more, fishable waters near the park’s margins appear to be more productive as a result of the park’s existence.
Although it’s among the largest Atlantic reef fishes, this distinctively striped predator blends well with its preferred backdrop of corals and rocky-bottom waters in the Caribbean and Central America. In 1900, the Nassau grouper was noted as typically weighing over 22 kg. Today, you’re lucky if you find one over 9 kg and more than 60 cm long.
Normally solitary, the Nassau grouper seasonally migrates long distances to spawn in gatherings historically numbering in the tens of thousands of individuals. (They release eggs and sperm into the water during spawning, so large groups increase the chance of fertilization.) The locations and times of the aggregations are highly synchronized—within about a week of winter full moons at approximately 60–80 sites across their range of distribution. It’s no surprise, then, that fishermen predict and regularly exploit the gatherings with handlines, traps, and spearguns. This results in the capture of the slow-maturing, long-lived fish (some reach 29 years) at its reproductive peak, often before it has had a chance to spawn. Furthermore, younger Nassau grouper appear to learn the aggregation locations from older ones. This combination of factors has resulted in the Nassau grouper becoming “commercially extinct” over most of its range. Every single aggregation site off the Florida Keys, the U.S. Virgin Islands, and Puerto Rico has disappeared. The Bahamian Nassau grouper are among the last fishable stocks, but populations there are in worrisome decline. Some aggregations in The Bahamas have vanished, and most of those that still exist attract only tens of fish.
Once the Caribbean’s most abundantly-caught fish, the Nassau grouper is now listed as endangered by the World Conservation Union and as a species of concern by the U.S. government. Stabilizing the species may hinge on establishing future marine reserves around known aggregation sites in the Bahamas.
Often found slogging along Caribbean seagrass beds with its single foot, the queen conch is a giant marine snail with a 30 cm long knobby shell lacquered pink, orange, or yellow on the inside. Queen conchs don’t move much, and can congregate by the thousands in just a few hundred square meters of shallow, sandy seafloor. This makes the slow-growing gastropod a sitting duck for easy collection by waders or free divers, usually showing up later as conch fritters on dinner plates or as shell jewelry on tourists. Today, queen conch fisheries have been significantly depleted in all parts of the Caribbean except The Bahamas, Belize, and the Turks and Caicos islands. While it is currently illegal in the United States to accept conch from certain Caribbean countries, Americans nevertheless consume 80 percent of worldwide exports. The species is currently listed as commercially threatened by the Convention on International Trade in Endangered Species. Catch of this species is currently limited with quotas in The Bahamas.
Caribbean Spiny Lobster
This shy, spotted crustacean is fished in coral reefs off Florida, in the Caribbean, and in the Gulf of Mexico. Without the pinching claws of its North Atlantic relative, the Caribbean spiny lobster relies on its spiky carapace for protection. That, and avoidance: During daylight hours, the lobsters seek refuge in clefts in coral reefs or, unwittingly, in open aluminum trapping boxes called “condos.” Sometimes fishermen use bleach, detergent, or gasoline to coax the crustaceans directly out of reef hiding spots. The Bahamas has the fourth largest fishery for spiny lobsters in the world (different species of the spiny or rock lobster family live elsewhere), and in 1997 the country exported 5.7 million pounds of frozen tails. Still, the Caribbean spiny lobster is on the verge of overexploitation across its range. Since larvae of this species flow to The Bahamas from the surrounding area, overfishing anywhere in the Caribbean could affect the lobster’s future in The Bahamas.
BREEF: Nassau Grouper Conservation
Information and links from the Bahamas Reef Environment Educational Foundation
BREEF: Grouper and Conch in The Bahamas
NOAA Office of Protected Resources: Queen Conch
MarineBio.org: Caribbean Spiny Lobster
More About This Resource...
Our innovative Science Bulletins are an online and exhibition program that offers the public a window into the excitement of scientific discovery. This essay was published in August 2005 as part of the Our Oceans, Ourselves Bio Feature.
- It begins by explaining that the bulk of fishing income in The Bahamas is brought in by three species, which are overfished elsewhere in the Caribbean.
- It then takes a look at how the Nassau grouper, queen conch, and Caribbean spiny lobster are maintaining a foothold in The Bahamas.
Supplement a study of biology with a classroom activity drawn from this Science Bulletin essay.
- Have students read the essay (either online or a printed copy).
- Working individually or in small groups, have them select one of the three species discussed to research further. (Point them to the related links on the essay.) Have students present their findings about the current state of conservation efforts to the class.