NOTE: This is a guest blog post from Ryan Kempster, a marine neuroecologist (sensory biologist) from the Oceans Institute at the University of Western Australia and founder of the shark conservation group Support Our Sharks. Ryan is currently completing his PhD research into the electrosensory capabilities of sharks and their relatives with the ultimate goal of refining and improving electrical repellent devices to better protect people in the water. You can learn more about Ryan and his research at www.ryankempster.com.
The most recent of these attacks was on a diver off the north coast of Rottnest Island on October 22. The other, involving a body-boarder, took place at Bunker Bay on September 4, and a disappearance at Cottesloe Beach on October 10 has also been attributed to a shark.
The proposed cull is a misguided attempt by politicians to protect beachgoers from potential attack. But is this the best way to deal with an animal whose natural environment we invade by the thousands every day? No; and this is why we are looking for your support to oppose such an ill-advised action by the WA government.
How many people are killed by sharks each year?
Although the Australian media continue to sensationalize the threat of shark attacks to swimmers, the statistics do not support these claims.
According to the Australian Shark Attack File (ASAF), sharks have killed 52 people in the past 50 years (1.04 per year) in Australian waters. Figures range from zero to three in a year (data correct as of October 24, 2011).
There’s no denying that each of these attacks is, of course, a tragedy. But the number of attacks is negligible when you consider the vast and increasing number of swimmers entering our coastal waters every year.
Are there more shark attacks?
Thousands more swimmers take to our beaches every year as the WA population and tourism continue to rise, so we might expect a corresponding rise in shark attacks. However, numbers of fatal shark attacks remain the same and within the expected yearly variation. Therefore, the number of fatal attacks in WA, per capita, is actually declining.
The number of shark attacks has nothing to do with how many sharks are in the water but everything to do with how many people are in the water.
Sensationalized reports will have us believe there are rogue “man eating” sharks patrolling the waters, with shark attacks on the increase.
But even if we consider the recent disappearance of a swimmer at Cottesloe beach as a shark attack (although unconfirmed), then in reality there have only been three fatal attacks in WA in the past 12 months.
The prime suspect implicated in all of these attacks is the species responsible for most fatal attacks, the white shark (Carcharodon carcharias). Since it was declared a vulnerable species in the late 1990s, there have been anecdotal reports that shark numbers have increased. Some say this is the cause of the recent shark attacks in WA.
“There is no scientific evidence to suggest that the short time period between these attacks is a reflection of an increase [in the] population size of white sharks.
“It could simply be related to the seasonal fluctuation of the number of white sharks within specific areas and that white sharks might naturally be more often occurring around the populated Western Australian coastline at this time of the year.”
Sharks are more use alive than dead
At this time, many people seem ready to begin a shark cull in a misguided attempt to feel more protected and to get revenge for the recent attacks. But we must keep a clear head and consider why sharks are in need of protection in the first place.
Most sharks serve as top predators of the marine food pyramid, playing a critical role in our ocean ecosystems. Directly or indirectly, they regulate the natural balance of these ecosystems, and are an integral part of them. Removing sharks from our ocean ecosystems is very likely to be ecologically and economically devastating.
Sharks are constantly misrepresented in the media as vengeful, deliberate predators of humans. It is, of course, nonsense. We must not allow this negative fictional image to form the basis of state or national policy.
Revenge is not a meaningful strategy on which to base policy nor is it worthy of an educated nation such as Australia.
Support shark conservation in Australia and oppose a cull by signing the petition to stop the shark culling in Australia.
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This post originally appeared on The Conversation.