In 2019 at least 79 million sharks died in fisheries, and at least 25 million of those belonged to threatened species—numbers that have stayed steady or even risen in the past decade.
Compared to 10 years ago, fewer of those sharks died because people cut off their fins and threw them back into the sea—a practice known as finning that is now prohibited in about 70 percent of countries and overseas territories. But regulations that have reduced the frequency of finning have not saved shark lives, an international research team reports in the journal Science this week.
“If anything, global shark mortality has slightly increased,” says Boris Worm, a marine ecologist at Dalhousie University in Canada. Now most sharks are landed whole, and a growing demand for shark products has driven fisheries to continue catching the animals. (Related: Shark fin is banned in 12 U.S. states—but it’s still on the menu.)
Worm and seven colleagues spent the past three years collecting data on shark mortality and fishery regulations. “This was really a challenge,” he says, “as shark fisheries are notoriously underreported. We compiled everything we could find, from catch numbers to data from observers on boats in international waters to estimates of coastal fishing that include recreational, artisanal, and even illegal fishing.”
The global analysis reveals that even though there has been a tenfold increase in regulations on shark fishing and finning, mortality in the past decade remained more or less the same, with estimates of 76 million dead sharks due to fishing in 2012 and at least 80 million in 2018. Given that not all catches are reported in sufficient detail and some aren’t recorded at all, the researchers say, the number of deaths is likely to be significantly higher.
A shark market
Marine ecologist Nicholas Dulvy of Simon Fraser University in Canada, who has not involved in the study, points out finning regulations did help “to ensure many catches could be identified to the species level, which is necessary for catch and trade limits” and also aids research. “Regulation of international trade has now begun, with the protection of over 100 shark species under the Convention on International Trade in Endangered Species of Wild Fauna and Flora,” he says. (Related: What is CITES?)
While these trade regulations appear to have led to fewer sharks getting killed in international fisheries, coastal fisheries have started catching more sharks.
To try to understand why that might be, the researchers interviewed 22 experts including scientists, conservationists, and people working in fisheries or companies that process shark products. “They’ve told us that existing markets for shark products have expanded,” says marine conservation scientist Laurenne Schiller of Carleton University in Canada, a co-author of the study. “Which may be due in part to the increased availability of sharks resulting from anti-finning regulations.”
Shark meat, even from endangered sharks, is increasingly found in a variety of food products, and not just in still-popular shark fin soup. Shark is also often used in fish and chips, in ceviche, or as a fraudulent alternative for swordfish.
In addition, shark cartilage and liver oil are common ingredients in the medical and cosmetics industries. “Many beauty products contain squalene,” Schiller says, “which usually, but not necessarily, derives from sharks. So it’s good to look for products that use plant-based alternatives instead.”
The researchers say that that to save sharks, anti-finning laws clearly do not suffice, and there need to be more extensive fishing regulations.
“There are 29 countries and overseas territories that have already prohibited shark fishing in their waters,” says Worm. “The Bahamas, for example, have discovered that sharks were worth much more as a dive attraction for the ecotourism industry, which is booming. On average, we see such prohibitions are the only tool that consistently reduced mortality, so we would encourage that.”
In places where people depend on fisheries for their livelihoods or sustenance, bans may not be appropriate, but keeping fisheries at sustainable levels is crucial to maintaining wild populations.
“This includes, of course, science-based catch limits for sharks,” says Schiller. “But many interviewees also told us about the dangers of unselective fishing gears, like gillnets.” These walls of netting that hang vertically in the water column are designed to catch fish by their gills, and they tend to entangle every animal that is too large to fit through the mesh. “Our own analyses show they are commonly used in the places we identify as mortality hotspots. So phasing them out and encouraging more selective practices in places like Indonesia, Brazil, Mauritania, or Mexico could have a big impact,” Schiller says.
“We know that shark populations are under enormous pressure from fishing throughout much of the world’s oceans,” says marine biologist Colin Simpfendorfer of James Cook University in Australia, who was not involved in the study, “and the data presented in this new paper add further evidence.”
While finning regulations have not led to decreased shark deaths, Simpfendorfer points out they weren’t designed to reduce catches, but to prevent suffering and the waste of sharks being killed for their fins alone.
Without increased efforts to protect sharks, at least one in three species will face the threat of extinction, and many more are suffering population declines.
“I have many colleagues who are oceanographers, and they tell me that in the 70s and 80s, there were always sharks following the vessel because of the kitchen scraps they threw overboard—typically oceanic whitetips, a formerly very abundant species that is now endangered and hardly ever seen. I’ve never seen one in my life,” says Worm. “That’s when you get that sinking feeling that something is really wrong with the way we’re treating them. We should fix that, and we can.”
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