After months of debate, a shark cull has begun in Australia. Over the weekend a large tiger shark was caught by local fishers using a drum line (a weight with a baited hook on one end and a float on the other), shot four times in the head and dumped at sea. Colin Barnett, premier of the state of Western Australia (which comprises the western third of the nation), claims that killing any large shark that approaches the beach will make swimmers and surfers safer. Ryan Kempster, a shark biologist at the University of Western Australia and founder of Support Our Sharks, counters that “there is no evidence that the current approach taken by the WA government will reduce shark bite incidents.” Indeed, the best available scientific evidence suggests that shark culls do not reduce the likelihood of shark bites.
The cull in Western Australia (WA) is remarkable for the level of opposition it has received. More than 100 shark scientists (including the author of this article) signed an open letter (pdf) stating their disapproval. A demonstration against it is believed to be the largest public protest in the history of WA, and a poll suggests that Western Australian citizens are against it by a three to one margin. An online petition opposing the cull has generated more than 70,000 signatures. Even local surfers whom the policy is designed to protect do not support it, and the family of a fatal shark bite victim does not either. International celebrities, including entertainer Ricky Gervais, are also adding their voices in protest.
With no evidence that culls make people safer and strong opposition from many fronts, why would the WA government adopt this policy? Christopher Neff, a PhD student at the University of Sydney who studies how shark bites influence shark conservation policy, has a theory: "The decision to move ahead with this drum line–shotgun policy is about trying to boost public confidence by killing sharks. This is about politics, not reducing risk, and the result is an unsound public policy that provides a false sense of security,” Neff says.
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
Kempster agrees: “The government is understandably in a difficult situation as they have to be seen to be doing something.”
Australia has generally been considered a leader in shark conservation. Great white sharks, designated as “Vulnerable” to extinction on the International Union for Conservation of Nature’s Red List of Threatened Species, are legally protected in Australia under its Environment Protection and Biodiversity Conservation Act, although the national environment minister recently exempted activities associated with the cull from this law. Ironically, when the great white shark was first listed under the Convention on International Trade in Endangered Species (CITES), the Australian government delegate noted, “No other species has been subject to such conjecture, so vilified, so targeted through fear.”
The official justification for the CITES listing, which was supported by Australia (pdf), includes the fact that “the negative image of the white shark and the fear it inspires in humans often precipitates unwarranted killing of the species…. Examples include campaigns to kill white sharks after shark attacks or in anticipation of such attacks and disregard of conservation and management measures.” When the Australian government promoted great white shark conservation through the United Nations Convention on Migratory Species (pdf), they emphasized that “great white shark populations are not adapted to cope with unnatural and sustained declines.”
Whereas culls are not likely to reduce the risk of shark bites, there are a series of alternative policies that can make people safer. By studying shark migratory behavior and observing where the animals are via aircraft, beach safety officials, swimmers and surfers can be better informed about when not to go in the water. Additionally, Kempster says, “there is an alternative approach to shark mitigation that has been proven to protect people and sharks. This involves capturing, transporting and releasing large sharks offshore and away from popular beaches and surf breaks. This approach that avoids the indiscriminate killing of sharks was recently tried in Recife, Brazil, and has been extremely effective in reducing the incidence of shark bites in protected areas. Even though scientists have recommended a nonlethal solution that is proven to work, the government has ignored it.”
As strong opposition to the cull continues, recent reports suggest that local activists are going so far as to remove bait from the drum lines used to catch sharks. Until the cull is called off the eyes of the marine conservation community are riveted on Western Australia.