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To the ancient Polynesians, sharks were gods or swift chariots used by sorcerers
to rove the seas, bringing death or ill fortune to their enemies. Today, some 35
years after Steven Spielberg's movie 'Jaws' first terrified cinema audiences, we
see sharks as a metaphor for evil -- killers without conscience. It hardly
matters that only a handful of the world's 450 species are considered
potentially dangerous to humans. Just the word 'shark' is enough to grip the
collective imagination and these 'monsters' hardly excite public sympathy. But,
their numbers are dwindling at such an alarming rate that the Species Survival
Commission of the International Union for the Conservation of Nature (IUCN) has
a Shark Specialist Group to study the problem. Unlike most fishes which spawn
thousands of eggs at one time, sharks -- most of which breed like mammals --
turn out only a few dozen or less a year. Even one of the most
prolific breeders, the blue shark, generates
only about 40 young a year. Sharks generally grow slowly and mature late, and
very few get the opportunity to live long, especially with the ever-increasing
demand for shark products: livers refined into smooth translucent oil for
cosmetics; dried cartilage used in cancer treatment and to make artificial skin
for burn victims; gall bladder extracts showing promise in acne treatment; and
teeth, marketed as popular jewellery items. Reports indicate that up to 73
million sharks are killed each year solely for these purposes.
Then there is humanity's feeding frenzy, especially shark-fin soup. Finning
is perhaps the most disturbing concern for conservationists. It is a simple but
brutal process whereby shark is caught, its fin sliced off, then dumped, often
still alive, back into the sea ! Bans on shark finning have been adopted for
most international waters but lenient standards and lack of enforcement
hamper their effectiveness. The hammerhead is amongst the most endangered
species from shark finning -- its meat, very low in value but its fins, highly
prized !
While some shark species have experienced an overall decline, some others
have been subjected to a total decline in a
particular region. For instance, scientists note a 50-70 per cent drop in the
blue shark population in the North Atlantic.
What effect does this have on the ocean ecosystem ? A clue is evident from a
study in which wolves and mountain lions, the apex predators, were removed from
a region of Colorado: the deer population boomed, exhausted its food supply and
eventually died of starvation. A similar fate could befall fish stocks and sea
lions if sharks continue to be eradicated.
With the inclusion of more and more names to the list of endangered sharks,
man's greed for short-term economic gains has apparently far exceeded the vision
required to maintain a proper balance in the biodiversity of our planet. |
