Nouméa resident Aline Guémas swims at the city’s beaches every day. She’s part of a snorkelling group at popular beach Baie des Citrons and says the waters are filled with life.
“It has exceptional biodiversity, almost half of the species present in New Caledonia inhabit its coral reef,” 65-year-old Guémas says. “Some endangered species come to reproduce here like the zebra shark.”
But for months, only part of the beach has been open to swimmers after a series of shark attacks. The incidents, one of which killed an Australian tourist, have prompted a culling programme and plans for a shark net – both of which have led to a backlash from scientists, environmental groups and many residents.
“People who usually frequent these waters know this and do not want any shark net to be installed,” says Guémas.
Rise in attacks
Culls began earlier this year and the government is due to install a 758-metre metal net at Baie des Citrons to act as an underwater fence and prevent sharks from swimming too close to the shore. The net is due to be installed by October.
It comes after Nouméa saw three attacks in less than a month earlier this year, including the fatal incident in February. Shark attacks have increased in New Caledonia in recent years and the country ranks 13th in the world for the number of attacks, according to the Florida Museum of Natural History. The rise in attacks remains poorly explained, according to shark scientist and behavioural ecologist Johann Mourier. He says attacks tend to be cyclical “with a lot of consecutive biting incidents and then nothing for several years”.
“Data tends to be erratic and there are many different underlying causes, from a lack of prey in high waters to feeding or sewage discharges attracting sharks to the shores.”
There is no data on shark populations around Nouméa. A study that began in 2018 was stopped before it could be completed because of an attack. Mourier said any statistics may be misleading as the sharks most associated with attacks, especially tiger sharks, regularly move around and change habitat, with some going as far as Australia and New Zealand.
Nouméa’s mayor, Sonia Lagarde, reportedly said in March that there was an “overpopulation problem” and “that we need to get rid of a certain number of [sharks]” . The culls are due to run until December, according to the Nouméa town hall. Analysis of public records and news reports shows at least 68 sharks have been killed since the first operation in April.
The mayor and the local government authorities declined to comment further on the culling programme or plans to install a shark net.
Those operations have been criticised by environmental organisations, including the International Union for Conservation of Nature, as targeted species responsible for attacks – the bull shark and tiger shark – are also vulnerable species. They had to be removed from local protection lists to enable the culling.
Mourier says “culling campaigns rarely work, they only serve to appease the population because of the emotion surrounding shark incidents”.
Sharks occupy a sacred place in indigenous Kanak culture, and are often protected rather than hunted as a result. “Sharks have a cultural importance for Kanak people … they need to be valued,” says Jean-Baptiste Juhel, a researcher in marine biology.
Net threatens biodiversity
Some scientists, including Mourier, see the proposed shark net as a better alternative than culling but say it may still pose a threat to biodiversity. According to the impact assessment commissioned by local authorities, the barrier would destroy part of the coral reef. Though the proposed net includes new technology iron mesh to limit the risk of wildlife being caught accidentally, it could still potentially suffocate “non-target species” such as turtles or leopard sharks, the impact assessment said.
Alexandre Henri, an auditor who lives in Nouméa, says the net will “reassure” swimmers but shares concern over the risk to sea life.
“I want there to be a place where we know it is safe,” the 26-year-old says. “The net will reassure people so I am in favour of the idea. But I still wonder if fish will get stuck in it or how it will impact the environment.”
Bastien Preuss, a marine biologist based in Nouméa, says the net will damage part of the coral reef and will prevent turtles and dugongs from entering the bay. Preuss adds the plan to install the barrier does not tackle the root causes of the shark attacks.
“Local fisheries fed sharks for over a decade and suddenly stopped, now fishing boats empty out thousands of litres of fishing juice onto the bay every day, constantly attracting sharks. So much public money has been poured into culling campaigns and barriers, but there are still some major issues we need to address [including] the sewage system.”
Shark nets have long been used in Australia but critics say they catch too many other species. Data published by the New South Wales government found almost 90% of animals caught in shark nets over a year period were non-target species including turtles and dolphins. Alternatives exist, including drone surveillance and smart drumlines.
“Nets have already been implemented in Australia and we know from their experience that it does not work and that it is not sustainable,” says marine biology researcher Juhel.
