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Threatened And Endangered Species Shark Essay

by Caty Fairclough

Sharks have been feared hunters ever since people first observed them swimming in the vast ocean. Yet today, sharks are declining rapidly on a global scale because humans have replaced them as the ocean's top predators. One way that humans hunt sharks is by using a practice called shark finning. This is the process of slicing off a shark’s fin and discarding the rest of the still-living body, often by dumping it back into the ocean.

Shark fins are tempting targets for fishermen because they have high monetary and cultural value. They are used in a popular dish called shark fin soup, which is a symbol of status in Chinese culture. In the past, Chinese Emperors favored the soup as a dish that honored guests because it was thought to have medicinal benefits and represented a victory against powerful sharks. This popularity has not faded with time and has even expanded with China's growing population. Today shark fin soup is still prevalent and has become a staple for more than just emperors on special occasions. As a result, fishermen have a large incentive to gather and sell shark fins.

Many fishermen prefer to practice shark finning instead of bringing whole sharks to the market because the fins are far more valuable than the rest of the body, sometimes selling for as much as $500 a pound ($1,100 a kilogram). Instead, fishermen choose to keep just the shark fins—only one to five percent of a shark’s weight—and throw the rest of the shark away rather than have the less valuable parts take up space on the boat. The finned sharks are often thrown back into the ocean alive, where they do not die peacefully: unable to swim properly and bleeding profusely, they suffocate or die of blood loss.

However, the animal cruelty implications are not the only reason to stop this practice. Another major factor is that shark fisheries—and finning in particular—are having catastrophic effects on shark populations around the world. Approximately 100 million sharks are killed globally each year, and one of the major incentives for this is the shark fin trade. With their slow growth and low reproductive rates, sharks are highly susceptible to extinction, and it is difficult for many shark species to replenish their populations as quickly as they are being diminished. Many species of sharks are currently in danger due to shark finning, including the scalloped hammerhead, which is endangered, and the smooth hammerhead, which is vulnerable according to the International Union for the Conservation of Nature. Between 1.3 and 2.7 million of just these two sharks are killed every year in the shark fin trade, and the northwestern Atlantic population of the scalloped hammerhead declined from around 155,500 in 1981 to 26,500 in 2005. Today, some shark populations have decreased by 60-70% due to human shark fisheries.

Such dramatic population plunges are not only dangerous for sharks but also for entire ecosystems. When shark populations decrease, a ripple effect can spread throughout the rest of the ecosystem. For instance, the loss of the smooth hammerhead caused their prey, rays, to increase. The larger ray population now eats more scallops, clams, and other bivalves. This not only hurts the bivalve populations and therefore the biodiversity of the ecosystem; it also harms human fisheries. Furthermore, many coastal populations make money from the sharks that entice vacationers to their communities for ecotourism. One estimate for hammerhead sharks suggests that a live shark, over the course of its lifetime, is worth $1.6 million, which is a great deal higher than the $200 the dead shark can sell for. A recent study from the University of British Colombia projected that shark ecotourism will be worth more than the global shark fisheries in just a few years.

Progress

Around the world, people are realizing how critical sharks are to ecosystems and people, and officials are beginning to protect sharks on a variety of scales. In early 2013, the Convention on the International Trade in Endangered Species of Wild Fauna and Flora (CITES) listed five more species of sharks in its Appendix II, a list of species that are not currently endangered but may become endangered without regulating their trade. Although Appendix II still allows trade in shark fins, the fishing is required to be sustainable, giving the species additional protection. Additionally, many individual countries are making their own protections. For instance, all sharks caught in U.S. waters must be brought to shore with their fins still attached according to the 2010 Shark Conservation Act. Since 1994, 22 countries have placed domestic regulations on shark finning. China is also working towards ending shark finning. To decrease the cultural value of fins, the Chinese government began prohibiting the serving of shark fin soup at official banquets in 2012.

Yet cultural values are slow to change, even with growing support to ban shark fishing from governments and celebrities. Many restaurants and hotels around the world continue to sell shark fin soup. One 2012 survey found that only six percent of luxury hotels in the Chinese cities of Beijing, Shenzhen, and Fuzhou had stopped serving the dish. To those who feel shark fin soup is a part of their culture, cutting it out of their diets completely is difficult. Some people support (pdf) increasing regulations on shark finning rather than banning it completely or using the whole shark so there is less waste and cruelty. Others remain staunchly against this process, making it difficult to resolve this debate. A variety of approaches may be the key to making progress in the future towards protecting sharks everywhere.

Tags: Shark finning, Endangered species, Sharks, Fisheries

Overfishing threatens to drive a third of the world's open-ocean shark species to extinction, say conservationists. Hammerheads, giant devil rays and porbeagle sharks are among 64 species on the first ever red list for oceanic sharks produced by the International Union for Conservation of Nature (IUCN).

Sharks are vulnerable because they can take decades to mature and they produce few young. The scalloped hammerhead shark, which has declined by 99% over the past 30 years in some parts of the world, is particularly vulnerable and has been given globally endangered status on the red list, which means it is nearing extinction. In the Gulf of Mexico, the oceanic whitetip shark has declined by a similar amount.

Scientists estimate that shark populations in the north-west Atlantic Ocean have declined by an average of 50% since the early 1970s.

Announcing the red list of open-ocean or "pelagic" sharks and rays today, scientists called on governments to set limits for catching the animals on the high seas and to enforce strict bans on "finning" – the practice of catching sharks, cutting off their fins and throwing the bodies back in the water.

"Despite mounting threats, sharks remain virtually unprotected on the high seas," said Sonja Fordham, deputy chair of the shark specialist group at the IUCN and policy director for the Shark Alliance. "The vulnerability and lengthy migrations of most open-ocean sharks call for coordinated, international conservation plans. Our report documents serious overfishing of these species in national and international waters, and demonstrates a clear need for immediate action on a global scale."

Pelagic sharks are usually caught on the high seas in tuna or swordfish fisheries. In 2007, 21 shark-fishing nations reported catching more than 10,000 tonnes of shark. The top five – Indonesia, India, Taiwan, Spain and Mexico – accounted for 42%.

At one time, sharks were considered worthless bycatch, but they are increasingly being fished on purpose to serve emerging markets for their meat and fins, which are used in soups and can fetch more than £100 per kilogram. In places such as China, shark-fin soup could once only be afforded by the elite, but the growing numbers of middle-class people in the country has driven up demand.

To satisfy the growing market, some fishermen have taken to finning sharks. There are bans on this practice in operation around the world, but Fordham said the coverage is patchy and, in any case, enforcing the bans is difficult due to a lack of policing on the high seas.

"The overarching problem for sharks is that, for a variety of reasons, they've been considered low priority and they're traditionally low value compared with something like the tuna," said Fordham. "Also public image feeds into that – I don't know if there are people clamouring for their conservation."

Most species of pelagic shark take many years to mature and have relatively few young when they do reproduce. The IUCN's report highlights a study by scientists in Canada which showed that the population of porbeagle sharks, classified as vulnerable in the red list, has been so affected by fishing that it will take at least 100 years to recover. Yet the government still allows the animal to be fished in its waters.

The global dusky shark popualtion, also classed as vulnerable by the IUCN, could take up to 400 years to recover because the animals are not sexually mature until around 20 years of age and usually raise only one offspring at a time.

Fordham said that because many of the sharks on the red list are at the top of the food chain, their extinction could also cause major local ecological problems. "We know that most of these species are top predators and we know that removing the top predators usually has negative consequences to the system as a whole."

In 2007, Julia Baum of the Scripps Institution of Oceanography in California, who is also a member of IUCN shark specialist group, published a study showing how a major decline in the numbers of predatory sharks in the north Atlantic after 2000 had allowed populations of cownose rays, which are their prey, to explode. The rays in turn decimated the populations of bay scallop off North Carolina. "There was a fishery for bay scallops in North Carolina that lasted over a century uninterrupted and it was closed down in 2004 because of cownose rays," she said last year.

Conserving threatened shark species might not be difficult. Last year, Peter Klimley of the University of California, Davis, found that scalloped hammerhead sharks migrate along fixed "superhighways" in the oceans, speeding between a series of "stepping stone" sites near coastal islands ranging from Mexico to Ecuador. Focusing marine reserves around these hotspots might be a cost-effective way to conserve the species.

The IUCN sharks red list is published a few days before Spain is due to host an international meeting of the managers of tuna fisheries, where many of the sharks are caught. Scientists are also meeting in Denmark this week to produce advice for authorities on how to manage populations of Atlantic porbeagle sharks. "The completion of this global assessment of pelagic sharks and rays will provide an important baseline for monitoring the status of these keystone species in our oceans," said Roger McManus, vice-president for marine programmes at Conservation International.

• This article was amended on Friday 26 June 2009. We referred to the the International Union for the Conservation of Nature (IUCN) as the World Conservation Union. It no longer uses this name. This has been corrected.

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