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The Harvesting Of Sea Cucumbers In The

Galapagos Islands Essay, Research Paper

Sea cucumbers in the Galapagos are being fished out illegally in spite of a four-year ban that is unsuccessfully enforced by the Ecuadorian government. Most sea cucumbers are dried and exported to Taiwan and Hong Kong. The waters off of mainland Ecuador have already been stripped of commercially valuable sea cucumbers. The controversy in the Galapagos involves the inability to sustain sea cucumber harvesting, and that the removal of millions of sea cucumbers will have detrimental effects on the food chain in the waters of the Galapagos. (Sullivan, 1999) Aside from the ecological damage, it is feared that these fishermen will go after other, rarer species when the sea cucumbers are depleted. (Stutz, 1995) It has been proposed to raise sea cucumber in captivity, but difficulties exist, such as locating the sexually mature sea cucumbers, the timing of mating the animals, providing the necessary food for the larvae, and then releasing the sea cucumbers at the right time. (Cohn, 1996)

The sea cucumber, or Cucumaria frondosa, make up the class Holothuroidae, of the phylum Echinodermata. The sea cucumber is related to the starfish, and can be described as big slug-like blobs. Sea cucumbers have a rubbery-like, warty body and their length can range from 0.8 inches to 6.5 feet. They have tube-like feet that project from underneath them and give them the sluggish caterpillar-like contractions as they move. Sea cucumbers breathe through branched respiratory tubes, or trees that go from the cloaca to the body cavity. The cloaca contract, forcing water into the respiratory. The water is emptied into the body cavity and mixes with body fluids and supplies the sea cucumber with oxygen. (Microsoft Encarta Encyclopedia 2000)

Sea cucumbers have a very important role in nature and maintaining the ecological balance in the sea. They prey on a variety of small organisms, which aids in controlling the population of these organisms. Decaying matter on the seafloor is food for the sea cucumber. The sea cucumber ingests seafloor sediments by swallowing large quantities, passing it through the intestine, and ejects the remainder. A large population of sea cucumbers within an area can process large quantities of sediments, and substantially change the composition of the sediments. (Encyclop?dia Britannica Online) The sea cucumber in the sea can be compared to the earthworm on land, as they turnover bottom sediments that helps to free nutrients. The sea cucumbers’ sperm, eggs, and larvae are an important source of food for organisms ranging from single-celled animals to fish. Sea cucumbers can account for 90% of the biomass.

The high demand for the sea cucumber can be attributed to it being a gourmet delicacy in Asia, and is considered to be an aphrodisiac as well as having medicinal properties such as being a treatment for high blood pressure. (Sitwell, 1993) The sea cucumbers’ flesh is made up of 50 – 60% proteins, which makes for source of high-quality food. When the waters of Micronesia were exhaustively harvested for the sea cucumber, fishermen set their sights first to Ecuador’s Pacific coast in 1988, and then to the Galapagos in early 1992. (Cohn, 1996)

The Galapagos is a cluster of volcanic islands that belongs to the province of Ecuador. The islands are located 600 miles from the coast of South America. The islands were named “Galapagos” after one of its inhabitants, the giant tortoise or galapagos. The bishop of Panama, Tom?s de Berlanga, happened upon the Galapagos Islands by accident in 1535 during his voyage to Peru when his ship had drifted of its course. Spanish voyagers of the 16th century used the islands as a place to stop, as did pirates and hunters. Ecuador took possession of Galapagos in 1832, after the area had set without colonization for almost 300 years. The English naturalist Charles Darwin’s visit to the islands in 1835 resulted in international fame for the area. Darwin’s theories on natural selection can be attributed to his visit to Galapagos. The native finches on the islands are commonly referred to as Darwin’s finches. (Encyclop?dia Britannica Online)

The ecosystem of the Galapagos Islands is very unique and attracted the imaginations of biologists and tourists for many years. The variety of animal and plant life that exists here are all resident species, of which their ancestors had to fly, drift, swim or hitched a ride there, because the islands were never attached to any other land mass. An astonishing fifty- percent of the birds and 95% of the reptiles, 42% of land plants, 80% of insects, and 17% of fish exist only on Galapagos. Along with the giant tortoise, other inhabitants are the Galapagos penguins, waved albatrosses, flightless cormorants, Galapagos fur seals, seagoing iguanas, three types of rice rat, Galapagos bats, and the blue-footed boobies (a type of seabird). There are thirteen species of the Darwin’s finch, which was used by Charles Darwin to illustrate his theory of evolution. (Lemonick, 1995)

Galapagos has a very fragile ecosystem that could be upset by a small change in the environment. Sea cucumber fishing can have a domino effect on the surrounding environment. The fishermen cook the sea cucumbers before exportation, thus utilizing the wood from the mangrove swamps. There are 336 types of algae and 400 types of mollusks that are directly affected when the ecosystem is upset by the over-fishing. (Trade Environment Database, 1994) Studies have shown that sea cucumber populations can be depressed for years after the over-fishing takes place. The over-fishing that occurred before World War II is still evident in that the population of sea cucumbers has not fully recovered. (Cohn, 1996)

In an effort to protect Galapagos, the islands were declared a national park in 1959. The Galapagos Marine Resources Reserve was created in 1986 to protect of the 29,000-square miles of waters that surround the island. The islands are now a biosphere reserve and the waters are a sanctuary for whales. Ecuador has a history of being very protective of its environment, and has been extremely strict with tourists. (Cohn, 1996)

The Ecuadorian government opened sea cucumber season to fishermen in October of 1994. The high price that is paid for these creatures attracted dozens of fishing boats. The government set a total limit to the number of sea cucumbers to be caught at 550,000. It is estimated that as many as 7 to 10 million sea cucumbers were harvested. The boats that arrived from the mainland to collect the sea cucumbers were carrying prostitutes and drugs. Some of the prostitutes were actually paid with bags of sea cucumbers that they could quickly sell for cash. (Lemonick, 1995)

The fishermen illegally went ashore to dry their catch of sea cucumbers in preparation for shipping. There were fears that because the fishermen left behind debris, that rats from the fishing boats would come ashore. The scientists were very concerned about the rats finding the reptile eggs. “Rats would absolutely devastate a whole set of species if they got ashore,” said Canadian ecologist Peter Bednekoff. (Langreth, 1995) Researchers are very concerned that mainland rats and other species that may have hitched a ride on the fishermen’s boats, which were anchored just off the islands. These rats could pose a serious danger to the species that are natural inhabitants of Galapagos. (Stone, 1995)

An Ecuadorian fisherman can make as much as $100 a day harvesting the waters around the island, as compared to the $71 a month that in the over-fished waters off of Ecuador. Along with sea cucumber, the fishermen are in search of lobster and shark for their customers in Hong Kong. The fishermen ruin the areas of the beautiful habitat by cutting down trees to set up camp, and leave behind trash and human waste.

The extreme over-fishing forced the government’s decision to shut down the sea cucumber season one month early. The fishermen were so outraged by the shut down, that with the help of an Ecuadorian congressman, they illegally seized the national park and research facilities. The three-day take-over was accompanied by threats from the fishermen to set fire to the habitat, kill rare animals, and take innocent tourists as hostages. (Cohn, 1996)

A six-year suspension on fishing and restrictions on lobster hunting was implemented in 1993. In an effort to ease tensions, the government started negotiations with the sea cucumber fishing industry in February of 1995. The government decided that the fishing suspension would remain in tact and the fishery closed. Because of the ban on industry and farming, the fishermen claim that there is no other alternative but to take advantage of the island’s resources. (Trade Environment Database, 1994)

Bibliography

Cohn, Jeffrey P. Jan 1996. Sea cucumbers and takeovers of scientific institutions. BioScience 46 (1): 70 (2)

Encyclop?dia Britannica Online. Sea cucumber; Galapagos. http://search.eb.com;

Langreth, Robert. May 1995. Showdown in the Galapagos. Popular Science 246 (5): 20 (1)

Lemonick, Michael D. Oct 30, 1995. Can the Galapagos survive? Time 146 (18): 80 (3)

Microsoft? Encarta? Online Encyclopedia 2000. Sea cucumber. http://encarta.msn.com

Sitwell, Nigel. 1993. The grub and the Galapagos. New Scientist 140 (1903): 32

Stone, Richard. Feb 3, 1995. Fishermen threaten Galapagos. Sea cucumber fishers demand fishing rights, threaten researchers and wildlife. Science 267 (5198): 611 (2)

Stutz, Bruce. May 1995. The sea cucumber war, Audubon 97 (3): 16

Sullivan, Ron. Summer 1999. Bio watch. Earth Island Journal 14 (2): 6

Trade Environment Database. June 1994. Sea Cucumber Loss in the Galapagos. Case Studies 146. http://www.american.edu/projects/mandala/TED/seacuke.htm.




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