THE PRIVATE LIFE OF THE CONCH

For those of you interested in getting a better understanding of the problems facing our conch fishery at Lac, here is a glimpse into the private life of our most interesting and appetizing marine mollusk. That's right, conch are simply overgrown plant-eating snails. But before that "grossed out" feeling comes over you - anyone who has seen them crawling around under water will confirm - the only label they should really carry is "cute". Their front end consists of a powerful arm for shoveling food, an elongated nose and two captivating eyes on the end of magnificent, retractable eyestalks. If this shy puppy could wag its shell, it surely would.

Only two species of conch (karko) occur on Bonaire. By far the most common is the Queen Conch (Strombus gigas) - this is the one we mean when we talk about "conch". But tucked in amongst the mountain of Queen Conch shells at Cai you will find an occasional shell which is much shorter and denser, less "spiney" and paler in colour. This is the shell of the Milk Conch (Strombus costatus). Both conch are herbivores (plant eaters) and live out their lives on sand flats and seagrass beds. They can be found from the Carolinas throughout the Caribbean and here on Bonaire their favourite spot is Lac.

Life as a drifter
Conch begin life as tiny larvae or "veligers", which hatch out of an egg mass a few days after it has been laid. They are about the size of a small pin head and are singularly unattractive, consisting of two round lobes fringed with minute hairs. The veliger immediately embarks on a shifting, vagrant life in the "plankton", a term used to describe all free floating plants and animals which drift passively along in the ocean currents. Some planktonic animals and plants spend the whole of their lives in this mobile, soupy state whilst others, like conch, are only temporary residents. Conch are unusual in that they can remain in the plankton for up to three weeks - plenty of time to drift a considerable distance on ocean currents and colonize habitats hundreds of miles from their original "home". They are the "Polynesians" of the temporary plankton.

What this tiny planktonic pioneer is searching for is a nice sandy place to settle. Once it finds a suitable bottom the veliger will bury itself in the sand and metamorphose into a perfect miniature conch. A lucky baby conch will then find itself in the perfect nursery: safe from predators and surrounded by a wonderful array of the most delicious miscroscopic plants. Think of it as a giant conch style Cultimara with no cashier. In Lac conch undoubtedly prefer the Awa di Meuchi where they will spend a year or more hidden from sight, slowly growing until they emerge onto the sand flats as a 10cm long "roller".

Growing up
Now life takes on a new tone. Suddenly the conch is supremely vulnerable. Just about everyone finds juvenile conch irresistible - other snails, fish, rays, turtles, lobster, crabs, octopus - and of course fishermen. Evasion is not an option. An athletic conch is able to cover about 100m on a good day and their sense of direction is erratic at best - not quite triathalon material but pretty good going for a gastropod. Instead conch try to remain inconspicuous, hiding amongst the seagrass, their shell covered in algae. They favour turtle grass (Thalassia testudinum) and must think of Lac - briefly - as "conch heaven".

Life as an adult
When left undisturbed conch prefer to live together in groups, adults aggregating in one place and juveniles of different ages clumping together in others. They eat plants, feasting on the tiny algae found on seagrass leaves and in the sand as well as on detritus (dead organic material). Hidden amongst the seagrasses it takes the juvenile conch another two to three years to reach 30cm and their final transition into adulthood. From our perspective the most profound changes are in the shell which thickens and develops a very pronounced flattened "lip" along the shell margin; though I'm sure conch notice certain "other" changes too. The bottom line is "no more rolling around on the bottom" - now they are ready for the serious business of reproduction.

Conch will mate whenever the fancy takes them between April and November. The female conch, having philandered with one or more males and finding herself thoroughly pregnant, lumbers off after about three weeks to lay her eggs. She will spend up to a day (often in deep water) laying a spectacular egg mass containing hundreds of thousands of eggs, which she promptly abandons and after a few days the life whole cycle starts over again.

What you can do
Think again before you rush off to Lac in search of conch for the dinner table or shells to decorate your garden wall. Taking conch without a local permit is against the law. Worse still leaving Bonaire with conch shells and no CITES documentation will land you in a whole heap of trouble with your local Customs Officers. There are hefty fines for smuggling products such as conch shells, turtle shell and corals which are all officially recognized as endangered species. Finally give conch a break at the restaurant too. Eventually we may have enough conch for local consumption but Bonaire will never be able to supply the international demand for conch meat.

Instead gaze, enjoy and leave our conch to the arduous business of munching their way across the bay unmolested and you can hope to have the pleasure of their company next time you visit Lac.

NOTE: CITES is the Convention in the Trade in Endangered Species. The Convention regulates trade in many internationally endangered species including things as varied as elephant tusks and conch shells.