Thursday, 12 April 2012

Sharks in danger of extinction

A thresher shark doomed by a gill net - Photo by/ Brian Skerry - National Geographic magazine

They belong to the super-order Selachimorpha and comprise 440 species, distributed all over the world. They are believed to have been in existence before the dinosaurs. In fact, scientists surmise that the earliest shark species swam earth’s waters some 420 million years ago.

All sharks are carnivores. However, their diet remains varied. Some species, including the mammoth Whale Shark, swim with their mouths open, allowing plankton and other small creatures to enter through huge filters.

The bottom-feeders crush crabs, clams and similar animals on the ocean floor and eat these at leisure, while the more ferocious species (such as the Great White and Mako sharks) actively hunt fish, squid, dolphins, seals and turtles. Feeding frenzies occur when a group of sharks come across a large school of fish or a similar assembly of potential prey. They begin to attack the prey from all angles in a crazed, uncontrolled manner. This results in the injury and even death of many fellow sharks.

When most people think of sharks, they automatically reference the man eating predators, however, there is more to this type of fish than meets the publics' eye. The facts about sharks, as well as the related concepts that are a part of them is one that can help to define this sea creature.

Not only do the evolutionary features define the look of a shark, but also determine how they survive in the wild. Not all sharks will constantly be searching in a particular area of the ocean for their food. There are three general types of sharks that will move according to the form and function of their body. This includes some sharks that will move at the upper part of the ocean and will move at a slow pace, sharks that will be towards the middle of the ocean and will have a powerful force while swimming and sharks that stay at the bottom of the ocean, moving slowly and finding their food on the ocean floor.




With the various areas that sharks live, are also specific ways of living. Depending on the type of shark, the fish will either swim in groups or on their own. This is dependent on the way that they have found it is best to survive, specifically with the hunting skills that they acquired.

The habitat of sharks not only takes place in different levels of the ocean, but also is restricted to different areas. This is based on the activities that are needed, whether they need fresh or salt water, seasonal changes that are needed and temperature of the ocean. Typically, most sharks will be based around the warmer parts of the ocean, ranging from the central regions of the Americas to places around the tips of Africa, Australia and India. There are also cold water sharks that will be further south or north in the ocean.


As top predators, sharks act as key elements in maintaining the balance of their ecosystem.  Any modification in their presence and abundance reflects on the entire ecosystem.  For example, the species whose numbers sharks used to police, such as ray and skates, are now exploding in population. They in turn are wiping out scallops and other shellfish, and water quality is suffering as a result. Reefs too are under assault, as parrot fish, which are key to controlling algae growth on reefs, are being exterminated by the fish whose numbers are no longer being regulated by sharks. This cascade effect can lead to unpredictable results.
As fascinating creatures, they play a major role in the Egyptian diving and ecotourism business.  Sites such as the Brother Islands, Daedalus Reef, Elphinstone and Abili Ali are well known among the diving community for the presence of oceanic white tip, silky, hammerhead and other beautiful pelagic shark species.  It has been estimated that the tourism industry has an annual income of EGP 1,250,000 from a single shark at Brothers Islands.
Looking at these considerations, the many catastrophic side effects of the depleation of the shark population is easy to guess.  Nowadays, main threats are identified in fishing and finning; activities that provide income by satisfying the commercial demand of shark meat and fins, as well as hides, liver oil and teeth.
 
Local fisher men - Photo courtesy by/ Hamed Gohar Museum - Hurghada
Up to 100 million sharks are believed killed worldwide each year solely for their fins. East Asian countries account for 95 per cent of all fin imports, officially reported at 7,000 tonnes annually but believed to be much higher. Commercial fishing is banned in Egypt's Red Sea marine sanctuaries, while a governor's decree prohibits shark fishing in most remaining territorial waters.

Local authorities deny that illegal fishing is a serious problem. "There is no shark fishing in Egypt because already the population of sharks is very low," says Mahmoud Hanafy from the Egyptian Environmental Affairs Agency (EEAA). He admits that some Egyptian companies are exporting a "small number" of shark fins, but says fishing vessels are probably catching these sharks outside Egyptian waters.
"If they catch sharks in Egypt, it is just by accident," he says. "It's not commercial fishery and there is no fishing for sharks using, for example, lines with many hooks."

Small Hammerhead shark in Egyptian super market - Photo by/ Dina Zulfikar

Dive boat captains returning from Egypt's southern Red Sea reefs suggest otherwise. One captain spoke of a long line discovered during a diving excursion in late 2001.

"We found a buoy and what we thought was a mooring line, but when we went to cut it we saw that it was a fishing line with 12 baited hooks," says Yasser El- Moafi, owner of the dive boat Royal Emperor. "On one of the hooks was a huge Mako shark."

El-Moafi has no doubt that the fishermen who placed the line were targeting sharks. "The hooks were baited with baby sharks, so definitely they were trying to catch sharks," he says. "While we were there a small boat approached, but when the fishermen saw us they ran away." Several journalists were on board the Royal Emperor at the time and this encounter was captured on film.

Dive boat operators say this was not an isolated incident. "There's finning going on in the deep south," says Amr Ali, managing director of Conquest Fleet. "You can see the shark hooks on buoys. There's tonnes of them."Ali reports shark long-liners to local authorities, but since the poachers operate hundreds of kilometres from the nearest coast guard base, he sometimes takes matters in his own hands.

"Now they run when they see us coming, because I gave a direct order to my boat crew to hit their boats," he says. "No mercy about it, we have to act." According to figures from the Food and Agriculture (FAO), Hong Kong alone imported 5,500 kg of dried shark fins from Egypt in 2000. About 75,000 sharks were slaughtered to meet the order.

Dozens of exporters openly advertise shark fins on the Internet. Minimum orders range from 100 to 1,000 kilos, according to the species and fin length. Even baby shark fins less than 15 centimetres are on offer. "It's a huge amount," says Ali. "Not all of this can be coming from outside Egyptian waters."

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