The bright blue skies and calm waters of the estuary belie rough conditions at sea, and there is no sign of activity among the colourful fishing boats moored around the harbour of Cananéia, a sleepy fishing town 160 miles south of São Paulo.
On the wharf, however, a delivery of frozen fish from Uruguay has just arrived and a few men in white gumboots are busy unloading pallets of beheaded specimens labelled Galeorhinus galeus – school shark.
These thin grey fish will be kept in a cold store on shelves already stacked ceiling-high with carcasses of blue sharks, all awaiting processing and distribution to cities inland.
“Why do we work with shark?” says Helgo Muller, 53, the company manager. “Because people like it; it’s good and cheap protein. It doesn’t give you crazy profits, but it’s decent enough.”
Shark is just a small fraction of the firm’s business but they process about 10 tonnes a month, he says, mostly blue shark imported from countries including Costa Rica, Uruguay, China and Spain.
Communities up and down Brazil’s 4,600-mile (7,400km) coastline have always eaten sharks. “It is part of our tradition,” says Lucas Gabriel Jesus Silva, a 27-year-old whose grandfather moved to the area in the 1960s to fish sharks for their fins.
However, the widespread appetite for shark meat that Muller’s company helps feed is now troubling scientists and environmentalists, who worry about unsustainable pressure on various species.
Demand has made Brazil the top importer and one of the biggest consumers of shark meat in a global market worth an estimated $2.6bn (£2bn).
“Sharks are very vulnerable to overexploitation as they don’t reproduce as often or with as many offspring as bony fishes do,” explains Prof Aaron MacNeil, of Canada’s Dalhousie University.
Research published in April found that 83% of the shark and ray species sold in Brazil were threatened, according to the International Union for the Conservation of Nature (IUCN) classification.
For years, conservation efforts focused on the fin trade with Asia and the barbaric practice of “finning” – removing a shark’s fins and returning the wounded and helpless animal, often still alive, to the sea. But research from earlier this year suggests restrictions on finning have not reduced shark mortality, with at least 80 million sharks still being killed annually.
“Meat was kind of left by the wayside,” says MacNeil, who is researching the global shark meat trade. “It’s only now we’re realising how big the trade is. Its value has certainly exceeded that of fins.” The pressure on sharks for food has risen in parallel with a decline in catches of other fish, he says.
Traditionally, Brazilians ate shark in moqueca, a seafood stew from the states of Bahia and Espírito Santo. And many of Cananéia’s residents recall how their older relatives would use shark’s head broth and cartilage as homemade remedies.
But now, sold in fillets or steaks, shark has been absorbed into Brazilians’ diet as it is cheaper than other white fish, boneless and easy to cook. It now appears in school and hospital canteens.
The fact that few Brazilians realise they are eating shark has probably helped make it ubiquitous. While coastal people with a shark-eating tradition recognise the subtle differences in texture and flavour between shark species, to most Brazilians it is just cação – a generic term under which both shark and ray meat are sold.
“Brazilians are very poorly informed – they don’t know that cação is shark, and even when they do they often aren’t aware that these animals are at risk of extinction,” says Nathalie Gil, president of Sea Shepherd Brasil, a marine conservation organisation.
In Cananéia, locals joke: “It’s cação when you eat it, and shark [tubarão] when it eats you.” But campaigners say the generic labelling prevents informed decisions by consumers, and this could even affect their health due to high concentrations of dangerous pollutants in these top predators.
“If they knew, they might not eat it,” says Ana Barbosa Martins, a researcher at Dalhousie University.
Brazilian law does not allow fishing for any sharks, but they can be landed as bycatch with few restrictions. The country’s tuna fleet often lands larger amounts of shark than tuna. “Theoretically, it’s all within the realms of the law. But it’s a form of fishing that’s completely unregulated,” says Martins.
The capture and sale of protected species is banned. If caught they must be returned to the sea, even if dead – which is usually the case, fishers say.
That rule is hard to enforce. Silva, the fisher from Cananéia, recalls how sand tiger sharks (known locally as mangona) were landed with impunity long after they became one of the first species to be listed as endangered in 2004. “Mangona was easily sold at the distribution centre. It was only in 2017, I think, the guys got fined and then it stopped,” says Silva. He claims fishers were unaware that it was protected.
Misidentification, whether accidental or deliberate, is frequent in domestic landings and imports. Paulo Santos, a biologist and shark taxonomist, identified a specimen in the Uruguayan shipment seen by the Guardian as a narrownose smoothhound shark, rather than the school shark listed on the label (both species are considered critically endangered in Brazil, but their import is permitted).
Martins believes effective monitoring depends on authorities better communicating and collaborating with fishing communities, who often resent restrictions that they consider unreasonable. This was evident in the views of local fishers along the São Paulo coast.
“Fishers don’t cast their nets to catch shark specifically, but sometimes a [protected] hammerhead comes up. What can you do?” says Lucia Rissato,who runs a fish stall in Peruíbe, a seaside town about 75 miles north of Cananéia.
Silva echoes a widely held view in his community. “A fisher’s got to do his job,” he says. “Prohibition comes with good intentions, but it doesn’t stop [sharks] from getting caught in nets that are set for Atlantic croaker, for hake.” He started going to sea aged 12 and believes shark populations have not declined “as much as people say”, another widely held opinion in Cananéia.
Last year, the government added five new species to its endangered list, including the shortfin mako, which is popular with consumers. Rissato complains that she can no longer sell any locally captured shark as it is not clear what is permitted.
“We have to sell it in secret, like drugs,” says the 48-year-old, who that day had a haul of Brazilian sharpnose shark in her fridge – a permitted species, but which she showed as furtively as if they were contraband.
Sixty-five year-old Ana Alinda Alves sorts fish at the wharf in Cananéia and has five sons who fish. “The authorities treat fishers like gangsters,” she sighs. “The fisher goes to sea, he gets a cação and he can’t even bring it home to feed his family. He didn’t steal anything. He went fishing, he went to work.”
Amid global efforts to improve protection of sharks, Brazil is taking action. A bill presented to congress last year would require cação to be labelled as shark (or ray) at every stage of the production chain, as well as identifying the species. Another bill proposes banning buying shark in public tenders. And for the first time, the government has introduced quotas for blue shark caught by Brazil’s tuna longliners.
But these provisions can only go so far, especially as they do not affect imports. Conservationists such as Gil argue that public opinion on these ecologically vital animals needs to change.
“Would they take a whale that got caught in the net and serve it to their family? No, because it’s illegal, but also because there is a respect for whales,” she says.
