Sunday, December 12, 2010

The Sharm shark mystery: why are the attacks happening?

Frightening: One of the sharks killed by officials who believed it was responsible for the attacks. But after this shark was killed, the attacks started again (Reuters)

From TheTelegraph

As arguably the world's foremost chronicler of
shark attacks, George Burgess knows better than anyone what the sea's most ferocious predator is capable of.

His position as curator of the
International Shark Attack File, a database started by the US Navy in the 1950s, has forced him to confront the results in mortuaries around the globe.
It is always a harrowing experience, one that demonstrates the fragility of the human body when faced with some of the most powerful jaws in the animal kingdom, as some of the more chilling entries in the shark attack file would attest.

Take the case of Shirley Anne Durdin whose head was decapitated and body torn in two after a White Shark attacked her as she snorkelled for scallops of the South Australian coast in 1985.
Then there was Theo Klein, disembowelled by another White that proceeded to tear chunks of flesh from his dead body in front of hundreds of horrified onlookers in 1971 after he was caught in its jaws off the breakers in Buffalo Bay, South Africa (see
Jawshark.com)

Perhaps because the file, which contains over 4,000 investigations of shark attacks dating back as far as the 16th century, is largely secret, Mr Burgess is reluctant to discuss recent individual cases.

But when it becomes to the business of killing, it is clear that some sharks go about their task with all the finesse of a medieval executioner faced with a treasonous Plantagenet courtier.
"If something is big enough to get its mouth around your head, the neck is very easily severed," he said. "It can be done in several bites or maybe in just one. A large, fully-grown white shark could cut a human in half."

As a scientist, who was drawn into his profession by reading the books of the oceanographer Jacques Cousteau as a child, Mr Burgess has little appetite for the gore of shark attacks that exercises so morbid a fascination on the rest of us.

Yet the bearded conservationist admits that the shark attacks that have taken place off the Egyptian Red Sea resort of
Sharm el-Sheikh in the past fortnight are "right up there" with the most fascinating investigations he has ever mounted.

Over the space of six days, sharks struck at swimmers in relatively shallow waters along a three-mile stretch of beach lined with some of the most exclusive hotels on the Red Sea Riviera. Four people were maimed and a fifth was killed.

Called in to investigate by panicked Egyptian authorities, Mr Burgess was swiftly able to establish that at least two of the attacks were carried out by the same oceanic whitetip shark, an astonishing revelation in a generally extraordinary case.

In recent years, experts have largely debunked the notion that single "rogue" sharks, unlike the predator dreamt up by the author
Peter Benchley in Jaws, ever strike more than one victim. Having discovered that the taste of human flesh is not to their liking, the vast majority of sharks do not make the same mistake again.

Yet photographic evidence clearly showed that a whitetip with a distinctive notch in its tail-fin attacked a Russian man on Nov 30, taking off part of his leg.

Six days later, the same shark returned to a nearby stretch of water by the Hyatt Regency hotel.
As her partner Rudi looked on in horror, Renate Sieffert, a German tourist who had been coming to Sharm el-Sheikh for 10 years, was pulled under the water.
Others swimmers described how she screamed as the churning waves around her turned red while the shark thrashed about, tearing at its victim.
By the time she was pulled ashore, Renate Sieffert was dead.

The whitefin has been all but absolved of involvement in two of the attacks, thought to have been carried out by shortfin makos, but remains a possible suspect in the mauling of Olga Martsinko, a Russian-Ukrainian woman.
So savage was the attack that her left buttock was ripped off, exposing the base of her spinal column.

Only once before has there been unimpeachable evidence of a shark striking more than one human victim.
In 1916, a great white killed four people and injured a fifth along an 80-mile stretch of shoreline off the New Jersey Coast.
The attacks captured the public imagination and became the inspiration for
Jaws.

Although Mr Burgess has investigated that case exhaustively, even recreating the attacks around Matawan Creek, where three of the attacks took place on the same day, he has never been able conclusively to prove why the shark behaved in the way it did.

But the most convincing explanation, he says, is that the great white was in some way injured or malformed, forcing it to attack humans because it was unable easily to hunt its normal prey.
The same may be true of the serial attacker off Sharm el-Sheikh.
"It is something we are looking at here," he said.
"Was this just a shark that made a couple of errors of judgment or decided that humans were ok, or was it an act of desperation by a shark trying to make a living in order to survive?"

Solving the mystery is a little like mounting a murder inquiry.
In the days he has been in Egypt, Mr Burgess has been questioning witnesses, studying photographs, forensic evidence and pathologist reports and scouring the waters near each of the incidents.
The most pertinent questions revolve around what the sharks were doing so close to the shore in the first place.
Both whitetips and makos are pelagic sharks whose natural habitat is far out to sea - and it is here where they are most dangerous.

Whitetips were involved in the deadliest attack on humans ever recorded when they attacked survivors pitched into the water after the USS Indianapolis was struck by a Japanese torpedo in the Pacific in the dying days of the Second World War.
Over 800 sailors survived the initial attack, but over the course of four days in which they trod water clung to flotsam and died of thirst and exposure, at least two dozen, possibly many more, were picked off by whitetips.

But until last week's attacks only two juvenile
whitetips had been seen off the coast of Sharm el-Sheikh all year, according to Elke Bojanowski, an expert on Red Sea sharks.

Preliminary findings suggest that humans, both directly and indirectly, are at the very least accessories to the crime.
Unusually warm water temperatures for the season, perhaps the result of global warming, may have lured the sharks into the northern reaches of the Red Sea, far from their normal habitats.

A ship carrying sheep from Australia is also a prime suspect, after it tossed carcasses and waste into the sea as it voyaged up the Red Sea.
With such a powerful sense of smell, sharks from 100 miles away could have been attracted by the ship - whose owners are facing possible litigation from the Egyptian government - according to Mr Burgess.
When the meat dried up, the sharks would have struggled to find food because of a dearth of tuna, their favoured prey, probably as a result of overfishing.

Despite everything he has seen, and although he nearly became one of his own statistics after narrowly escaping an encounter with a
Lemon Shark by attempting to bop it on the nose, Mr Burgess is a true shark lover.
Sharks may inspire a visceral, even primal fear in humans, particularly after Jaws - a film Mr Burgess says set back the cause of shark conservation by 20 years - but in reality they pose us little danger.

There are an average of five shark-related deaths a year.
By contrast, human beings kill up to 75 million sharks annually, for their fins, a delicacy in China, their meat or simply as bycatch.
With some species seeing their numbers fall by 99 per cent in 50 years, the king of the seas is facing a battle for its survival.
Which is why, he says, it would send the wrong message to hunt and kill the sharks responsible for the Sharm el-Sheikh attacks.
Doing so would not make the beaches safer anyway, something that would be better achieved by increased monitoring of the seas so that beaches can be closed - as happens in America - when sharks are spotted close to shore.
"To catch that animal, you are going to have to find it first," he said.
"That's a lot of expenditure in human time. But in the end what have you got? Sure, you have some retribution for what it did but you have no assurance it was going to do it again and no assurance that its mates won't do it again."

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