13 January 2009

Human-eating sharks?

I believe more people eat sharks than sharks eat people. But three attacks on swimmers within 24 hours over Sunday and Monday have fuelled a fevered debate over whether overfishing has put man on the menu.

"Humans are next in line on the food chain," veteran shark hunter Vic Hislop told commercial radio. "It will definitely get worse."

Experts say there is no scientific evidence to support his claim that reducing the shark's natural prey through overfishing has produced a spike in attacks.

NSW Department of Primary Industries shark biologist Vic Peddemor said Mr Hislop's theory was wrong and attacks on humans were almost always a case of mistaken identity.

"It's complete and total rubbish," Dr Peddemor said.

"Most species of shark have evolved over millions of years to eat very specific prey items.

"There are only a handful of sharks capable of eating large marine mammals and of the ones that come close it's the tiger shark, the bull shark and of course the great white.

"They are designed to eat marine mammal fat and blubber and we don't have that.

"Even our blood is very different to that of marine mammals so they haven't evolved to have the taste for either our body tissue or blood."

Despite three attacks on humans in the past two days, Dr Peddemor said shark attacks were still very rare considering the "millions of man hours" we spent in the water.

"Occasionally somebody will get bitten and it's inevitably a case of mistaken identity," he said.

There were five key things to remember if you were trying to avoid a shark encounter, Dr Peddemor said.
  • Don't swim at dawn, dusk or at night-time.
  • Don't swim in murky or turbid water.
  • Don't swim alone.
  • Don't swim in or around river mouths.
  • Don't swim where there are schools of fish or birds diving into the water.


Full reports on the wildsingapore news blog.