Species Loss – The Queen Conch
It is under increasing stress from: urban development, increased boating, especially marinas, anchors which break coral and sewerage, calamitous hurricanes which disrupt habitats and the use of chemicals which destroy marine ecosystems, coral and fish.
He stated that global temperature increases are also a consideration as they result in coral bleaching. These factors, and increased dumping of sewage at sea, and cause coral disease, represent the greatest threats to the marine life of The Bahamas and life as we know it today.
He set the stage by enunciating the main problems facing The Bahamas marine environment, including: Lost wetlands and marine nursery areas through construction, road building, poor drainage and urbanization.
Also, the degradation of coral reef systems due to the loss of prime predators, bleaching, raw sewerage and boat anchors, and the targeting of spawning aggregations by fisherman, which eliminates species before they achieve sexual maturity, and as a result they do not have an opportunity to breed before they die.
Species Loss
To bring the message home, the former Minister of Agriculture & Fisheries and Ambassador for the Environment spoke on the "Species Loss" within the territorial waters of The Bahamas in an address on 21 July.
He explained that conch is a stressed species fast becoming endangered. "More than 90 percent of the conch landed in many parts of The Bahamas do not reach sexual maturity. If they are not caught after they are sexually mature, they do not have the opportunity to breed and produce offspring. Without breeding and offspring, there can be no future generations of conch to harvest and enjoy."
Of the beloved grouper, he noted that grouper aggregations in The Bahamas are the last remaining in the western Atlantic. The stocks are declining from over-fishing and lack of protection.
Large predator stocks are being targeted by fisherman, and as a result, grouper, shark, swordfish and tuna are reaching critical lows. The result is the loss of the ecosystem's ability to sustain itself.
While discussing sponge, Deveaux said that sponge is still being harvested in unsustainable ways, contributing to the loss of habitat, re-growth and the spread of disease.
Turtles, while protected internationally are still being hunted and consumed in The Bahamas. Lean snapper aggregations are targeted by fisherman using nets and mutton snappers are aggressively fished during spawning aggregations.
In this article we will focus on the Queen Conch.
The Queen Conch
"The Bahamas has the fifth highest landings of queen conch in the region." Department of Fisheries.
The Department of Fisheries publishes a brochure, "Conch Facts -Important Things You Should Know About The Queen Conch."
"The Queen Conch, whose scientific name in strombus gigas, is a marine snail indigenous to the sub-tropical and tropical waters of the Western Atlantic Ocean." The brochure continues, "Typically they are found in seagrass meadows, on the sandy flats or around reefs in depths that range from a few feet to more than one hundred feet."
The Queen conch is described as "a large, moderately heavy cone-shaped shell with short, blunt triangular spikes. The exterior of the shell is brown/orange in colour with a bright pink flaring lip in mature adults. The exterior is usually covered in algae. It has a gray, mottled head with long black eye stalks and proboscis. The body of the conch is white, except for the mantle or sand skirt, which is reddish/pink in colour. The hard dark brown claw is actually a toenail. This is used to drag the conch along the seabed."
The rub comes with the age of the conch at maturity and how to identify a mature conch. "Conchs reach sexual maturity at 3 1/2 to 5 years, stop growing in length and develop the characteristic flaring lip. This lip thickens with age. The sexes are separate and physically distinguishable.
A mature male conch has a verge and the female conch has an egg groove.
Mating occurs during the warm months of the year.
The brochure continues, "A gravid female lays several crescent-shaped egg masses on clean, sandy flats. Each egg mass contains up to 400,000 eggs. Within 3 – 5 days the larvae emerge from the egg mass as microscopic plankton known as veliger. the veliger develops floating within the sea currents feeding on microscopic plants (phytoplankton).
The full development of a veliger takes twenty-one to twenty-eight days, following which the animal transforms into a miniature conch that settles to the seafloor. "These miniature conch settle in areas that may be many miles from where the egg mass was laid. Immediately they conceal themselves during the day from predators and feed on algae during the night. Turtles, porcupine fish, eagle rays, stingrays, octopus, tulip snails, hermit and blue crabs are natural predators of juvenile conch."
The Department of Fisheries research has found that the maturing conch moves to deeper water after their first birthday and feed on organisms that grow on sea grass, detritus and algae. At this time the conch extrudes a "clear, jelly cord or pistel; this contains enzymes that assist in the digestion of algae."
It is important to understand the importance of conch in economic terms to appreciate that conch must be protected and not harvested until they are mature and able to produce eggs. The Department of Fisheries indicates that the major percentage of conch landings occur during the months of April – July when the lobster season is closed.
There are fisheries regulations to control the harvesting of conch in The Bahamas. These regulations state that no harvesting, possession or sale of conch without a well-formed, flaring lip is allowed. Non-commercial export of conch or conch by-products without a licence issued by the Minister responsible is permitted.
All conch products exported are subject to inspection by a fisheries Inspector. Foreign sports-fishermen with a valid sport-fishing permit are limited to ten (10) conch per person on a visiting vessel. Conchs cannot be harvested with the aid of SCUBA gear.
International Regulations: The Queen Conch is protected under the convention for International
Trade of Endangered Species of Fauna and Flora (CITES). The Bahamas is a signatory to this convention that demands all international trade of conch is done under the provisions of a CITES permit. In The Bahamas, the Department of Agriculture is the management authority for CITES.
While currently, the fisheries regulations state that conch may only be harvested when the shell possesses a well-formed, flaring lip, other forms of management are being actively considered. These include the proposal for a closed season during the summer months when conchs spawn, establishing a Marine Fisheries reserve within selected areas, and enforcing a minimum legal size for harvest, based on the sexual maturity of the conch.
In its most recent newsletter, the Perry Institute for Marine Science/Caribbean Marine Research Center (CMRC), (June 3, 2003) devoted front page coverage to "Protecting the Queen Conch." It recounts dialogue between a CMRC volunteer and a veteran fisherman in Exuma. Knowing that the veteran fisherman regularly harvested juvenile Queen Conch, the volunteer approached him to ask if he knew that the harvesting of juvenile conchs was illegal? The fisherman responded that he did not know "it was illegal to take the conchs, nor did he believe that it damaged their population to take the smaller animals. He felt this was a story perpetuated by some businessman intent on keeping the conchs for his own profit."
In a second discussion, the volunteer took Erin Rechinsky, CMRC Research Associate along to chat with the fisherman. They took one of CMRC's posters with them. The poster illustrates the Life Cycle and ecology of the queen Conch. The Newsletter notes that the fisherman studied the poster and "expressed surprise at the challenges faced by the conchs in reproducing and surviving, and thanked her (Erin) for taking the time to provide him with that information." The article concludes with the following facts. "While mature Queen Conch have very few predators, during their juvenile stage they have many. Spotted Eagle Rays, Loggerhead Turtles, Octopus, Spiny Lobster, and Hermit crabs, are just a few. Spending the first 3 1/2 years of their lives in shallow water, the juvenile conch are easily accessible by these predators, as well as humans who collect them illegally. After 3 1/2 years, the queen conch reach sexual maturity at which time they can begin to reproduce."
The inevitable conclusion is drawn that, "knowledge of how these animals and other life in the ocean works is important for effective management of the oceans. This knowledge is not only important to conservationists and marine scientists, but also to the local island communities who depend on their resources to survive."
Source: The Nassau Guardian
