A controversial shark cull claimed its first casualty this weekend in Western Australia, when a commercial fisherman shot and killed a tiger shark off of Old Dunsborough (map) in the southwest region of Western Australia.
In a move late last year that has since sparked protests, Western Australia premier Colin Bennett announced a shark cull to control populations of great white sharks off of popular beaches in the region.
This was in response to the fatal attack on surfer Chris Boyd last November.
The cull—which will run from January to April of this year—includes deploying as many as 72 baited lines attached to drums and anchored to the seafloor to catch sharks over 9.8 feet (3 meters) long. Sharks smaller than 9.8 feet (3 meters) will be released.
The lines will be anchored 0.6 miles (a kilometer) from shore in a number of heavily trafficked areas.
A spokesman for the Western Australia government confirmed that the first fatality was a 9.8-foot (3-meter) long tiger shark, according to news reports. The fisher—contracted with the government to monitor the baited lines—shot the animal in the head and took the body out to sea.
Reactions to the start of the shark cull on social media range from anger to sadness.
— Friends of Hector (@HectorBlueShark) January 27, 2014
— pgnprincess (@amandalisa_45) January 27, 2014
Researchers have also expressed concern about the strategy of culling sharks to control populations.
More than 100 shark scientists, including me, oppose the cull in Western Australia : http://t.co/nlQsJMbRzb
— David Shiffman (@WhySharksMatter) January 27, 2014
Shark culls performed in Hawaii in the 1950s showed “no measurable effect on the rate of shark attacks on people,” said Chris Lowe, professor of marine biology at California State University, Long Beach, who analyzed the data taken during those culls.
“The bottom line is that the practice didn’t seem to work, at least not in the state of Hawaii.”
“You would have to really knock down shark populations considerably before you could influence the rate of shark attacks,” he explained. (See “Maui Death Raises Questions About Spike in Hawaiian Shark Attacks.”)
There are so many unknowns when it comes to shark populations, Lowe said. “We have no idea how many sharks are out there, and we don’t know how many we have to kill to reduce the instances of shark attacks.”
“The fact that you can start a culling program with so much unknown is worrisome and disheartening,” said Amanada Keledjian, a marine scientist with Oceana.
Both Lowe and Keledjian worry over the unforeseen and unintended consequences of removing large predators like sharks from the environment.
Keledjian noted there was no way of knowing what other animals like dolphins would end up dead—either caught in a shark barrier or hooked on a baited line.
Lowe added that telling the public an area has been culled could result in people thinking all is well and that they can engage in risky behavior when they go back into the ocean. (See also “How Should We Respond When Humans and Sharks Collide?”)
“People start going further offshore, they might start going to more remote places,” he said. “They start doing things we tell people they shouldn’t do.”
Keledjian and Lowe stress that it’s important that people know the ocean can be dangerous. “It’s a wild place, it’s not Disneyland,” said Lowe.
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