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What You All Should Know About Great White Sharks
A real star for pictures: Great Whites at work and play
Feared and Maligned, Generally Unjustly
She averages 15 feet in length, but has surpassed thirty; has a huge jaw a man could sit in, lined with multiple rows of formidible triangular teeth, measuring more than 3 inches (8cms) long; just reaching early maturity, she weighs 1.5 tons (3,000,plus, pounds).
Her bite exceeds 20 tons per square inch enabling her to easily remove a foot-square chunk of meat in a single snap from a whale or any other of her prey creatures.
She is, of course, "Carcharonon carcharias," the Great White Shark, also called "White Death," "White Pointer," or, merely, "White Shark."
Great Whites are of the order, Lamiformes, and she is the ultimate form of power and savagery that evolution has produced of this shark family, which include other great killers, smaller sharks and even some plankton eaters. I commenced calling her "She," as the female of this species is the larger and more dominant.
(I was prompted to add to the screeds already written about the Great White after reading about another fatal attack of a surfer in Western Australia this week. Google Chris Boyd, Gracetown for press details. The unlucky victim died almost immediately as is the fate of many the Great White targets for a meal. Locals are debating whether to attempt to cull the protected sharks in near coastal waters).
Does this perfect destroyer of fish and sea mammals, found in all the world's oceans, deserve its unsavoury reputation? You might find two schools of thought here: the defenders of these incredible creatures and those who would sweep the seas clear of all sharks which have acquired the reputation of man-eaters, even though they rarely do so and then almost never devour Homo sapiens whole.
When we examine Great White attacks on whales, sea-lions and seals, etc., it is easy to see man, at best, would only be a tasty (or less so) snack for a shark of this size. There are reports of a 13-year-old boy swallowed whole and many of seals and sealions being found intact inside captured Great Whites. More commonly, pieces of the victim have been found, especially human legs, hands, and even in one verified report, a penis with testicles attached! If that was me, I'd beg the shark to finish the job.
One reason Whites are so feared by people who need share their environment with them is that when this creature is hungry, the up to 40 mph attack is so swift and implacable, that the shark is seldom seen until a second before the strike. Other documented man-killing sharks, like Tigers, Makos and the rest, generally circle around and even make an exploratory visit to the potential prey, brushing past or even nudge the swimmer with its nose, giving the diver a chance to make a defensive move, or at least empty his bowel.
There is little hope of a defense if a Great White has decided to make you into dinner. The main chance the injured swimmer has is the shark will lose interest or be repelled by the strange taste after chopping off a leg or taking a large chomp from a victim's body. If he can apply a torniquet, etc.; escape the water soon and get aid, he may have a chance to save his life, although he will be severely injured with deformities and/or scars he or she will carry for the rest of this life. Few contacts with hungry Whites end any better than this, even a curious taste is like a brush with a buzz-saw, usually resulting in extensive repair to the fragile swimmer.
Readers wishing to study the experiences of three surviving victims of a savage mauling by a Great White should Google Fox, Rodger and Bource, seperate attacks in the 1960's, but a good insight on what a Great White attack can mean...and they are not the worse on record by any means.
Perhaps due to man's excesses in catching fish in the area, the seas off San Francisco have become a focal point of Great White attacks, rivalling seas off South Africa, close to one hundred having occured since the 1970's. This may also be due to the proliferation of the Pinnipeds - seals and sea-lions - protected since 1972, and which have drawn the great predators to the area and the swimmers and scuba-divers have been mistaken for these marine mammals, favorite prey of Whites. We have all seen the documentaries showing a seal or sea lion being taken from the depths by a large shark and then being propelled many feet into the air as they are hit at perhaps 20 to 40 miles per hour by the predator. This fate has sadly overtaken several human victims of shark attack.
Fossils of all sharks are hard to find, due to the fact their skeleton is of cartilage, rather than bone and only the teeth survive well in the fossil record. We do document remains back to 16,000,000 years in the Miocene period where the Great White shared the seas with another larger carnivore, Megalodon, which may have reached lengths of more than 60 feet.
The creatures prefer water temperature of around 12 to 24c degrees; are able to make long migrations solo or in small groups - South Africa to Australia is nothing for them. They can thrive and feed in shallow coastal water, or dive for food to 4,000 feet. They are the apex predator although there is some evidence they fear the Orca Gladiator (Killer Whale). It's the old tiger versus lion nonsense with the stronger - and wiser - Orca being obeserved killing smaller Great Whites which they may not like one bit. Where marine creatures are concerned, it's usually size that is the determining factor on who is predator to whom, and who wins battles. Pound for pound, the Orca is stronger and a better swimmer as well as being more courageous and far more intelligent. Great Whites do not commonly kill the ganged-up Killer Whales, but they do take smaller marine mammals such as porpoise, dolphin and the pinnipeds, of course. (All of which are on the Orca's menu as well). I doubt, however, a single Orca of any size would want to take on a 20-foot Great White with its superior bite size and weight...I guess it's all down to heart.
Great Whites, like most sharks, are well adapted for success as predators in their world. They have immense bite strength, rows of teeth which are replaced as needed and the amazing "Ampullae of Lorenzini," sensitive receptors which can detect the electro-magnetic fields of moving creatures, down to one half-billionth of one volt! Better turn your pacemaker off before you go surfing.
Along with the up to 300 razor-sharp, serrated teeth, with back-ups like bullets in a magazine, and allowing them to bite through a turtle as if it were butter, they can even seriously damage shark cages made of hardened steel, causing the inmates watching to add a very smelly chum to the water. Great Whites have an exceptional sense of smell allowing detection of a drop of blood in the water a mile away.
Like Orcas and Makos, they can "spy-hop," using their powerful tails to lift their heads from the water to check on their prey. One gazing down on you in the lilo might cause an instant cardiac arrest. White Death is indeed the master predator of the seas and if they really targetted humans we would not be able to enter the sea in safety again. In truth, they don't and attacks are so rare you might well be as easily struck and killed by lightning. Sometimes it appears otherwise as, like airline crashes, the results of Great White attacks are so dramatic, the world press focusses on them and many people collectively fear enjoying the delights of the oceans again. Films like Jaws have not helped here.
They can migrate and live without feeding for some time due to stores of fat in their huge livers and provided they don't piss off a bigger Orca, there's nothing in all this expanse of ocean to fear. Except, or course, man. Shark fishing kills millions of the species and is often criminally wasteful as the valuable fins are cut off and the creature left to die in agony. Yes, the bloody Chinese market for shark-fin soup, etc., again despite all activists are trying to do to stop it. Luckily, really huge Whites will rarely be captured.
But they are listed as "vulnerable" on the IUCN list of endangered species...
Other sharks have really committed many attacks attributed to Great Whites. The standout is the Tiger Shark, which can grow to a huge 15 feet long or more and often displays a savage nature. Australia, in particular, has recorded many attacks from Tigers, a large percentage, fatal.
Most sharks do not bother man, yet any large predatory shark is capable of biting a man in the water...many other species have, and they should all be treated with respect.
Like our lions, tigers and all the rest, they are dangerous yet magnificent and it makes me want to puke thinking of grubby little Chinese quacks making a fortune from their demise...