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Sharks 'forced' to eat humans CA FAIS 14 PERSONNES CETTE ANNEE MORT PAR DES SHARKS
Sharks 'forced' to eat humans
http://network.news.com.au/image/0,10114,5068204,00.jpg Hungry ... more great white sharks are attacking humans due to a lack of fish / AP
A MAJOR decline in fish stocks in Australian waters is leading hungry great white sharks to switch prey and turn to humans as a food source.
Fish stocks, including tuna, snapper, kingfish and mulloway, had declined by up to 95per cent in the past 60 years, leaving sharks hungry, said Scoresby Shepherd, a marine biologist at the South Australian Research and Development Institute Aquatic Sciences.
"Given the rapidly increasing frequency of attack over the same period, hungry sharks will explore alternatives, such as humans," Dr Shepherd said.
"There's been an increase in the number of people in the water; there's also a decline in natural prey."
CSIRO research has shown that over-fishing has led to a 95 per cent drop in tuna stocks, while poor river flows have led to a 95 per cent decrease in mulloway. Dr Shepherd said kingfish stocks had fallen, too. "If the prey declines, the sharks have to switch to other things," he said.
A significant increase in New Zealand fur seals in Australian waters over the past two decades has provided a good source of food for average-sized and large sharks, which Dr Shepherd said could also result in increased attacks on humans.
Research from the US also showed a direct link between growing seal colonies and increasing shark attacks.
"The increase in shark attacks in California may well be to do with confusing (people) with seals," he said. "Ninety per cent of attacks occur at or near the surface.
"Seals are very important prey, and then there's the ease with which they (sharks) can be confused ... you can see an increase in attacks was quite likely."
Shark expert Andrew Fox doubted sharks would be "switching prey", but agreed that sharks could confuse people with seals.
"We're the same size, we're often the same shape, we set off the same electric field, particularly on a low-vision day or if you're swimming near a seal colony," he said. "We're just a marine mammal. However, we do get rejected on most occasions." There have been 26 fatal shark attacks in Australia over the past 20 years, including two in South Australia and one in Western Australia since July last year.
http://network.news.com.au/image/0,10114,5068204,00.jpg Hungry ... more great white sharks are attacking humans due to a lack of fish / AP
A MAJOR decline in fish stocks in Australian waters is leading hungry great white sharks to switch prey and turn to humans as a food source.
Fish stocks, including tuna, snapper, kingfish and mulloway, had declined by up to 95per cent in the past 60 years, leaving sharks hungry, said Scoresby Shepherd, a marine biologist at the South Australian Research and Development Institute Aquatic Sciences.
"Given the rapidly increasing frequency of attack over the same period, hungry sharks will explore alternatives, such as humans," Dr Shepherd said.
"There's been an increase in the number of people in the water; there's also a decline in natural prey."
CSIRO research has shown that over-fishing has led to a 95 per cent drop in tuna stocks, while poor river flows have led to a 95 per cent decrease in mulloway. Dr Shepherd said kingfish stocks had fallen, too. "If the prey declines, the sharks have to switch to other things," he said.
A significant increase in New Zealand fur seals in Australian waters over the past two decades has provided a good source of food for average-sized and large sharks, which Dr Shepherd said could also result in increased attacks on humans.
Research from the US also showed a direct link between growing seal colonies and increasing shark attacks.
"The increase in shark attacks in California may well be to do with confusing (people) with seals," he said. "Ninety per cent of attacks occur at or near the surface.
"Seals are very important prey, and then there's the ease with which they (sharks) can be confused ... you can see an increase in attacks was quite likely."
Shark expert Andrew Fox doubted sharks would be "switching prey", but agreed that sharks could confuse people with seals.
"We're the same size, we're often the same shape, we set off the same electric field, particularly on a low-vision day or if you're swimming near a seal colony," he said. "We're just a marine mammal. However, we do get rejected on most occasions." There have been 26 fatal shark attacks in Australia over the past 20 years, including two in South Australia and one in Western Australia since July last year.
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