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Much about the lives of Great White sharks remains a mystery.
Off the West Australian coast, a shark approaches a boat
where Doug Coughran works with shark researchers to ascertain
whether it is possible to put tags on these animals
in order to assist in measuring their distribution and abundance.
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Photo: Courtesy of Doug Coughran, CALM |
April 19, 2002
Great White Sharks
Real Audio
28k
Log Transcript
This is Genevieve Johnson speaking to you from the Indian Ocean.
In 1958, an eminent Swedish scientist, Carlos Linnaues, suggested that Jonah was not swallowed by a whale, but by
a Great White Shark.
Great white sharks, also called the white pointer or white death, are perceived as man-eaters - ruthless, bloodthirsty
killers - monsters guarding their oceanic territory, patiently waiting for an unsuspecting, hapless human to innocently
stumble across their path and be devoured!
The reputation of Great White Sharks has been sorely damaged through misrepresentation by the media and popular
writers. The star of film and literature, the mere mention of this shark's name elicits terror in most peoples' minds.
Such irresponsible publicity is unwarranted and has led to a rapid increases in the number of Great White sharks killed
around the globe with the result that Great White sharks have recently been added to the CITES
(Convention for the International
Trade in Endangered Species) list of endangered
species. Today we spoke with Doug Coughran of Conservation and Land Management of Western Australia.
The nature of his job has led him to several encounters with great white sharks in the wild.
Doug Coughran:
Great whites are protected under the State legislation. There are two acts under which it is protected Ð
the Department of Conservation and Land Management is the department I work for,
they administer the Wildlife Conservation Act and under the Wildlife
Conservation Act, the Great White shark has special protection status. It's also protected under State Fisheries
legislation and Federal legislation.
Genevieve Johnson:
There is no question that sometimes these animals do attack and eat people. Although having being around for almost
400 million years, they have obviously not evolved to consider humans as a regular part of their diet. So why do sharks
occasionally attack people?
There are probably two main reasons. The first is that some attacks may be related to threats and aggression,
similar to a guard dog defending its territory from an intruder. However, the most likely reason may be as simple
as a case of mistaken identity. When viewed from below, the silhouette of a person on a surfboard can look
remarkably similar to that of a seal, the favored prey items of larger great whites. Attacks at the surface of
surfers and skin divers have prompted scientists to propose the 'bite and spit' theory. Unfortunately, we are
comparatively awkward in the water, our jerky movements coupled with splashing and yelling may be mistaken
for an injured fish or mammal in distress at the surface, an easy meal. The sharks initial attack on pinnipeds
frequently involves a single massive bite that inflicts an injury that is meant to incapacitate the prey in order to
prevent injury to the shark from sharp teeth and claws. Unfortunately, in humans, this first bite is sometimes fatal.
Usually no flesh is removed until the second attack, interestingly though, humans do not often experience this second
attack. Perhaps the shark has realized its error in biting this boney creature with little valuable fat or blubber!
In reality, great white sharks are in far greater danger of being attacked by humans then we are from them. Blaming a
great white shark for attacking a human is akin to blaming a lion for attacking a person who walks in front of it if in the
African savannah. For piece of mind, it helps to have an intellectual understanding of shark behavior and a realistic
understanding about the almost negligible probability of an attack. It also helps to bear in mind that when you choose
to enter the sea, you are entering a world that is wild, natural and not always predictable.
From a statistical perspective, shark attacks are extremely rare events. To a victim, however, a small statistical probability is cold comfort when your encounter with a great white has become a complete certainty. Remarkably, some survivors of Great White Shark attacks including Australians Rodney Fox and Henry Bource have since dedicated their lives to developing a better understanding of these much maligned and misunderstood animals, while educating the public about the value of living sharks.
The Great White Shark is unmistakable in the ocean. It is robust and torpedo-shaped, with a conical snout and differs from its closest relatives in having nearly symmetrical triangular, serrated teeth. It is also huge! It lives in all of the world's oceans, but appears mostly in the coastal and offshore waters of the cooler temperate areas of North America, Southern Africa, and Southern and Western Australia.
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Doug Coughran, Supervising Wildlife Officer,
Conservationn and Land Management (CALM), Western Australia.
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Photo: Courtesy of Doug Coughran, CALM |
Little is known of its biology and behavior. Doug Coughran explains.
Doug Coughran:
As far as the population for the West Australian coast goes, we simply don't know.
The sooner a research project is up and away, the better. As far as the knowledge of
Great Whites in Australian waters goes, and probably globally, it's unfortunately lacking
a lot of good science to establish a lot of good management decisions.
Genevieve Johnson:
We do know however that compared to other species, great whites are not particularly abundant.
They require more than 10 years to reach sexual maturity, have a low birth rate and give birth to very
few young. All of these factors combined means it is possible for humans to so deplete their numbers
as to leave them vulnerable to extinction.
Sharks around the world are under siege and the Great White is no exception.
Of the more than 400 species of sharks, only a handful, which includes the Great White, are responsible
for about 50 attacks a year. Very few of these attacks are fatal. In comparison, hundreds of millions of
sharks are caught in global fisheries annually either by accident, or increasingly for use in shark fin soup
and as fillets, none of these animals survive their encounter with humans.
It is frightening when we realize that the great white shark - a marvel of evolution, together with many
other terrestrial top order predators, including tigers, bears and wolves - and there are countless more,
are in fact the unfortunate victims of man. An ever expanding, multiplying super species that now occupies
every corner of the globe, systematically eliminating, any potential threats or competition to himself, from the
face of the earth and in this case from the sea, before taking the time to learn about them and appreciate their
role in the oceanic ecosystem.
Log by Genevieve Johnson
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