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Cull or be killed: is this really the solution to stop shark attacks?

In Western Australia, politicians and members of the public are calling for a shark cull in response to the state’s recent shark attack fatalities. 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…

Shark_hermanus_backpackers
Culling sharks is unlikely to make our beaches safer. Hermanus Backpackers

In Western Australia, politicians and members of the public are calling for a shark cull in response to the state’s recent shark attack fatalities.

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. A disappearance at Cottesloe Beach on October 10 has also been attributed to a shark.

The proposed cull is an attempt to protect beach-goers from potential attack. But is this the best way to deal with an animal whose natural environment we invade by the thousands every day?

How many people are killed by sharks?

Although the Australian media continue to sensationalise 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.

In reference to two fatal shark attacks in 2004-05, Dr. Rory McAuley, shark research scientist with the WA Department of Fisheries, said it wasn’t unprecedented to have a sudden rise in attacks: “Those isolated incidents don’t represent a trend” he said¹.

Are there more shark attacks?

Thousands more swimmers take to our beaches every year as the WA population and tourism continue to rise. 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 media will have us believe there are rogue “man eating” sharks patrolling the waters, with shark attacks on the increase.

Sharks are part of a complex ecosystem. Terry Goss

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.

Dr Charlie Huveneers, a white shark researcher at Flinders University and the South Australian Research and Development Institute’s (SARDI) Aquatic Sciences division, told me:

“There is no scientific evidence to suggest that the short time period between these attacks is a reflection of an increase 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”.

Additionally, Dr. Rory McAuley said:

“The problem is, we don’t have much data and, from the available data, we have yet to see evidence that recovery has started to take place”¹.

To put things in perspective, on average there are two to three deaths per year from bee stings in Australia; yet we don’t see people suggesting there should be a cull of bees.

This may be because bees, like sharks, are important both ecologically and economically. We accept the minor danger that bees present and act in a way that reduces our own risk of exposure.

(Of course, bees don’t grow to six metres in length and have huge teeth – fear can be a powerful motivator).

Can we avoid sharks?

So why can’t we accept the risks that sharks pose and reduce our risk of exposure, as we would with bees?

Actually we can: we know that most shark attacks occur under very specific conditions. It’s about when and where you swim and what you do in the water.

The Rottnest Island diver was alone and spear fishing at the time of the attack.

It's difficult, but important, to be rational about shark attacks. Mila Zinkova

The body-boarder attacked at Bunker Bay was close to a seal colony at the time of the attack.

Finally, in the suspected attack on a swimmer at Cottesloe beach, the victim was said to be swimming alone a few hundred metres away from the shore in the early hours of the morning.

Each of the conditions surrounding these attacks will increase the likelihood of encountering a shark. Simply being aware of these conditions and acting appropriately will dramatically reduce the already minute risk of being attacked.

The ASAF provides the following advice:

  • Swim at beaches that are patrolled by surf life savers.
  • Do not swim, dive or surf where dangerous sharks are known to congregate.
  • Always swim, dive or surf with other people.
  • Do not swim in dirty or turbid water.
  • Avoid swimming well offshore, near deep channels, at river mouths or along drop-offs to deeper water.
  • If schooling fish start to behave erratically or congregate in large numbers, leave the water.
  • Do not swim with pets and domestic animals.
  • Look carefully before jumping into the water from a boat or wharf.
  • Do not swim at dusk or at night.
  • Do not swim near people fishing or spear fishing.
  • If a shark is sighted in the area leave the water as quickly and calmly as possible.

Sharks are more use alive than dead

This is a difficult time. Many people seem ready to begin a shark cull in a misguided attempt to feel better 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.

References:

  1. Weekend West, October 15, 2011

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14 Comments

  1. Nathan Hart

    Nathan Hart

    Associate Professor

    logged in via email @uwa.edu.au

    Well done, Ryan, for providing a level-headed assessment of the recent attacks. These are terrible personal tragedies, but the answer is proper education of the public of the major risk factors, not wholesale slaughter of sharks.

    1. David Trescuri

      David Trescuri

      Student

      logged in via email @bigpond.com

      I too would like to congratulate you for this level headed, responsible and encouraging article. I have been most disheartened in the Western Australian Government's suggestion of a cull.
      Having grown up in a coastal community (not too far from Bunker Bay) I like many locals accept the risk of what happens when we go into the water. Personally, I think the money that would be spent on a cull would be better spent in signage and other education methods. I would much rather people choose to not go…

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  2. Paul Crooks

    Paul Crooks

    logged in via Facebook

    Statistics confirm a human arrives in Australia from overseas a little less than every 2 minutes.
    Statistics confirm that the majority of tourists will at some point visit popular coastal regions.
    Statistics confirm that an increase of professional and recreational marine users continues.
    Statistics confirm that a myriad of changes within the Ocean environment is unquestionable.
    Statistics confirm that Great White numbers have dramatically reduced to its threat of extinction.
    Statistics confirm…

    show full comment
  3. rob alan

    rob alan

    IT Tech

    logged in via email @bigpond.com

    Good article, thank you.

    Great Whites don't hang around, studies I've seen involving the satellite tracking of Great Whites in SA show they cover thousands of miles each year doing the rounds.

    From my own experiences encountering sharks while snorkeling the SA reefs, the creature seems no more than a little curious with a hint of dry humor when having a look at yah.

    Where there are schools of snapper there are sharks. Diving to me is akin to jumping into the amazon with only a wet-suit as protection. Don't want to risk being accidental prey yourself be it just as taste test then don't go where sharks feed.

    Below sea level is a beautiful place and I'd encourage all parents to show their kids just how wonderful it is down there. Use a shark shield till you get your footings. Past that stay in the shallows, lots to see there at very low risk.

  4. Mick Chubb

    Mick Chubb

    Health Professional

    logged in via email @gmail.com

    I'm surprised you didn't use the old, "you have a higher chance of being hit by a bus than being killed by a shark" statistic as well". Of which I reply, "no I can simply look both ways prior to crossing the road. Good luck evading a shark in over waist deep water, even if you do see it coming".

    Every time someone is killed by a shark we hear the same old rhetoric about statistics & yes there is no research to suggest the short time between attacks is due to an increase in the population of white…

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    1. David Trescuri

      David Trescuri

      Student

      logged in via email @bigpond.com

      Nick as a fellow West Aussie from the Southwest I agree that 'swimming between the flags' is not feasible, there are no flags within half an hours drive of where I live in a major coastal town. However, I find the idea of culling disconcerting; other places around the world are utilising alternative methods and I think these should be explored before we do something irreversible.

      The fear based rationale that is being used to push for this cull is truly frightening. I recently read in an online…

      show full comment
  5. Melissa Carmichael

    Melissa Carmichael

    logged in via Facebook

    Brilliant article!

    In my opinion follow the guidelines or deal with the consequences. We are all aware it's a risk of swimming in the ocean but it seems to me some people blame sharks as though they should know better, how ridiculous! It is their natural environment and we should let them be!

    I would much rather see valuable money and time go towards research to better understand these animals behavioural patterns, into improved education and awareness campaigns and perhaps into approriate deterrant technology. We simply don't have any right to go out and cull these animals!

  6. chris dawe

    chris dawe

    El Studente

    logged in via email @gmail.com

    Great read Ryan.

    It is utter craziness that politicians and others wanting Great Whites to be killed. I have even read that they are going to find that specific shark that attacked that American bloke off Rotto, impossible! How are you going to find that 'one' shark? Oops wrong one lets try another?

    As someone else said they are an endangered species we cannot just go out and start culling. We are entering their habitat by swimming/surfing in the ocean plus the guy who was attacked was not far off a salmon farm in Rottnest. God knows what affect worldwide fishing industries are having on marine ecosystems.

    At the end of the day everyone knows what risks are involved when swimming or surfing and killing sharks is not the answer. Have we not evolved from being so primitive?

  7. rob alan

    rob alan

    IT Tech

    logged in via email @bigpond.com

    Some thing to chew over: includes sources.

    ISAF 2007 Worldwide Shark Attack Summary

    "Death Total Lowest In Two Decades"

    Source: http://:www.flmnh.ufl.edu/fish/sharks/statistics/2007attacksummary.htm

    Statistics on White attacks, fatal included in Australia from 1791_2004

    State,Total attacks, Fatal attacks, Last Fatal attack

    NSW_ 238_72_1993 Byron Bay

    QLD_221_71_2004_Opal Reef

    WA,_70_12_2004 Gracetown

    SA_46_20_2004 West Beach

    VIC_32_7_1977 Mornington Peninsula

    TAS_21_5_1993 Tenth Island…

    show full comment
  8. Paul Whyte

    Paul Whyte

    Formulations Chemist/Director

    I liked the article.

    I do think it is worth a mention that Shark Shields do work and could have prevented the attacks if worn and turned on.

    I've been SCUBA diving for 7 years and find a lot of denial in the industry about the threat of shark attack and discouragement towards using these proven devices.

    While most operators will tolerate their use many would rather yu did not have the device turned on.

    At about $600 the device is not cheap but how much is a life worth?

    I always ware mine turned on when I'm swimming or diving to the relief of some companoins and mild disapproval of others.

  9. Shirley Birney

    Shirley Birney

    retiree

    logged in via email @tpg.com.au

    *The media reported that Premier Colin Barnett said he would consider allowing commercial fishermen to increase their catches of shark
    along the WA coastline in a bid to reduce numbers.

    *The government said it would consider mass shark culls and aerial patrol of the Rottnest coast.

    *For the first time in WA history, Fisheries Minister Norman Moore issued a directive for fisheries officers to trap and kill the beast that attacked the hapless victim off Rottnest.

    I think these directives and considerations say more about Colin Barnett and Norman Moore’s bloodlust than they do about the shark’s.

    1. David Trescuri

      David Trescuri

      Student

      logged in via email @bigpond.com

      I could not agree more. I have just quickly scoured the net and come up with pages of counter arguments to take to a public meeting with fisheries tomorrow night... haven't even got to my uni library yet.

  10. Paul Burton

    Paul Burton

    Professor of Urban Management and Planning at Griffith University

    The logic of hunting and killing the shark in question is interesting: previously of good character, it went off the rails and now has a taste for humans and must be removed; it has committed a sin and must be punished accordingly; we must send a clear message of deterrence to other sharks that we will not tolerate this anti-social behaviour in the future. Once this has been sorted, perhaps we can turn our attention to badly behaved grizzly bears in Yellowstone national park and to the recidivist tigers languishing in Dreamworld here on the Gold Coast?

  11. Doug Overton

    Doug Overton

    Person

    logged in via email @bigpond.com

    I note the article attracted a comment that I paraphrase as human beings should be free to do whatever they like, whenever they like, wherever they like. Activities like surfing for example. Technology allows our growing and empowered population to go anywhere they like, such as Great White habitats, swim in all seasons and often affect a confusing appearance not unlike the seals that probably inhabit those areas which both Great Whites and people seeking recreation frequent as well. Unlike the…

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