A Conch by Any Name is Disappearing
The huge pile of conch shells that can be found on almost any eastern Caribbean island serve as a testamony of the importance of this large marine snail to the culture, ecomony and diet of the islands. Whether you call them conch (US and Bahamas), lambi (Eastern Caribbean), carrucho (Puerto Rico) or cambombia (Panama) these giant snails have been an important part of the history of the Caribbean. There are several species of conch, but the conch used for food is commonly called Queen Conch (Strombus gigas).
Queen conch can be found throughout the Caribbean, from Florida and the Eastern Caribbean islands into the southern Gulf of Mexico, and to the Orinoco River in Venezuela. Conch is usually found in sand, sea grass, coral rubble or algae areas and usually in depths less that 90ft.
Conchs are vegetarians and eat alga that grows on sea grass and the sea floor detritus. They use their proboscis to pick up and eat the algae. Conch move using a ‘claw’, a hard appendage that is also their operculum, or the cover for their shell. Unlike most snails, the operculum does not entirely cover the entry of the shell. Conch can travel up to one kilometer in a single night, but more often they travel about a quarter of that distance and their travel rate changes with the seasons.
Queen Conchs usually mate on sandy substrate in shallow water. Females lay egg masses with about half a million embryos. It takes about five days for the embryos to hatch and travel to the surface. These are called veligers and they drift in the ocean for about three weeks. When they are about the size of a grain of sand, they settle to the bottom. At this point they have developed a tiny transparent shell called protoconch with a foot and a mouth. Juvenile conchs are small versions of the adults with larger spikes on their shell; the spikes wear down as the conch matures and sand abrades the shell. They reach a shell length of close to three inches after one year and five inches after two years. Food availability influences conch morphology and growth. It takes about four years for the queen conch to reach maturity and they can live to twenty years or more.
Conchs have fed the people of the Caribbean for a very long time. They were a staple of the Amerindian diet. They are easy to dive for in the shallow water and once you get the hang of cleaning them, they can be easy to prepare and very tasty to eat and provide a high quality protein. Humans are not the only predator of conch. Spotted eagle rays, octopus and starfish are known to prey on conch. The rays use their powerful jaws to crack the conch shell. Starfish insert a leg into the conch shell. And because the operculum does not entirely close the shell, the octopus can get a leg in and invert their own stomach and digest the conch. Octopus have the eight leg and suction cup advantage and pull the conch out and eat them on the spot.
Conch shells are used for horns and many Caribbean towns use the blast of a conch trumpet to signal the arrival of fresh fish. Slaves used conch horns to communicate from hill to hill. Some cruisers use the blast of a conch shell to signal a setting sun. Conch shells are used for house and fence building, and for jewelry. In the Bahamas men eat the ‘pistol’, which is the long gelatinous tube of the penis. They firmly believe this will increase their sexual powers.
Conch are a renewable resource, but the harvest must not exceed the recuritment.
Queen conch are slow growing; it takes about four years to grow an adult conch, so it is easy to strip out the adult conch population in an area. Ask any conch diver and they will tell you they have to go further and deeper to harvest queen conch. The commercial market for conch has driven the harvest rates beyond sustainable rates. The Turks and Cacos have developed a conch farm, but ultimately that is not the answer. Conch play an important role in the ecosystem and farm conch will not fill that need.
Each country has it own regulations and havest limits of conch. There is usually a minimum shell size or a minimun thickness of lip that determines a legal take. What we can do is follow the regulations and try to purchase conch from fisherman who follow the regulations.
Devi Sharp is a retired wildlife biologist who spent many years exploring the Caribbean with her husband, Hunter on their sailboat Arctic Tern.
Caroline Rogers is a Marine Ecologist with the USGS Caribbean Field Station in St. John, USVI, and has been conducting research and taking photos in the Virgin Islands since 1984. Caroline has two underwater photography books available on Amazon: Â Coral Reef Stars and The Mysterious, Magical Mangroves of St. John, U.S. Virgin Islands.
Devi Sharp has written for ALL AT SEA since 2008.
Worth your time?
Thanks — noted.
