Great white shark attacks: Is culling the answer?

great white shark
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(CBS News) The spree of fatal shark attacks off the coast of Western Australia has prompted local officials to call for an end to the "protected species" status afforded to great white sharks. Some have even called for a culling program to drastically lower the population of sharks in the water. But would such a program cause more harm than good?

The death of 24-year-old surfer Ben Linden over the weekend was a brutal reminder of the recent surge in shark attacks. Linden was the fifth person in ten months to be killed by a shark.

"This has been a growing problem, not just a passing one," said Dr. Bob Hueter, director of Mote Marine Laboratory's Shark Biology and Conservation center in Sarasota, Flordia.

Many have pointed to the great whites' protected species status as a possible cause of the increased attacks. The ban on killing great whites has caused the shark population to surge, resulting in more cases of shark injuries.

But, speaking with CBS News, Dr. Hueter believes it is the increased human presence in the waters, not sharks, that is contributing to the problem.

"What people are doing is they're venturing out in Western Australia, further offshore into the feeding grounds of the sharks and they're putting themselves at risk." Dr. Hueter said. He believes that a culling program would be far more difficult and expensive - in addition to being potentially harmful to the ecosystem - than a simpler program of human awareness.

"You really can't manage fish, you can only manage people."

Speaking to Australia's ABC television, Australian fisheries minister Norman Moore said, "I think we need to have another look now to see whether or not there's been a significant increase in great white numbers since they became protected. And if that's the case, should they still be on a protected list?"

Dr. Hueter argues that it is nearly impossible to gauge what effect the great whites' protected status has had on the population. He points out that great white sharks are extremely rare, and believes there are "dozens of animals, not hundreds" off the Australian coast.

Allowing fishers to kill great whites could have far reaching consequences beyond the shores of Australia. Sharks are migratory animals, and great whites can range hundreds of miles. Dr. Hueter points to one shark that had been tagged for observation travelling from the coast of South Africa to Western Australia - traversing the entire Indian Ocean.

Any culling program would also affect the ocean's ecosystem in ways not easily understood. "There's plenty of evidence now that having healthy numbers of [sharks] is important to the health of the general ecosystem." Dr. Hueter says. He points to one incident where a program to remove sharks from a coral reef led to a cascading effect on the ecosystem that ultimately resulted in the death of the reefs.

In a certain light, the spree of shark attacks in the past ten months serves as a reminder of just how rare fatal shark-related incidents really are. Speaking with BBC News, John West, curator of the Australian Shark Attack File, said that fatal shark attacks average around one a year over that past two decades. He contrasts that with the fact that there were 87 drownings per year.

Dr. West does acknowledge that shark attacks have increased over the past decades. A 2011 study published in "Marine and Freshwater Research" showed that the total number of shark attacks in Australia rose from 6.5 incidents per year between 1990 and 2000 to 15 incidents per year in the past decade.

Even if a culling took place and fishers were allowed to kill any sharks they caught, it is unclear if such a program would have a lasting effect.

"These animals are mobile and migratory," Dr. Hueter told CBS News. Even if the entire great white population off Western Australia was destroyed, "other sharks would move in."