Hundreds of kilometres of mangroves and coral reefs, as well as humpback whale breeding grounds, are under threat from an oil spill that has polluted more than 2,400km of Brazil’s north-eastern coast in the last two months.

The Brazilian Navy, which has deployed 8,500 personnel, 30 ships and 17 aircraft in the cleanup operation, said this week that 4,200 tonnes of oil have been removed from beaches, amid fears by scientists that some has already entered the food chain.

“There are still many indirect impacts that have not yet been properly shown,” said Guilherme Dutra, director of Conservation International’s marine programme in Brazil. “The risk of contamination of the food chain is very high, especially in areas directly affected.”

The government of President Jair Bolsonaro initially struggled to react to the spill, leaving volunteers to clean up. On Wednesday it staged Brazil’s biggest-ever oil auction for ultra-deep-water rights, which raised $17bn (£13bn) – a disappointing shortfall on the $26bn the government had hoped for.

Mangroves and coral reefs are particularly vulnerable to damage, scientists said, and removing oil from them is a delicate, specialised and lengthy process. Detergents used to clean oil can damage coral reefs, and mangrove roots need to be cleaned manually.

Brazil’s government environment agency, Ibama, has counted 126 marine creatures affected – including 24 seabirds and 88 turtles – of which 95 had died, it said on Tuesday. Another 3,900 baby turtles had been captured by government agencies and universities and moved to safety.

Facebook Twitter Pinterest A volunteer shows his protective gloves encrusted with crude oil spilled at Praia de Busca Vida beach in Camaçari, Bahia state. Photograph: Mateus Morbeck/AFP via Getty Images

The Brazilian navy says the oil has reached the Abrolhos Marine national park off the coast of Bahia state – a reserve that includes an archipelago, extensive coral reefs, humpback whale breeding grounds and the South Atlantic’s biggest concentration of marine biodiversity.

Reef fish such as Scarus trispinosus – a vivid blue parrotfish known as Budião-azul in Portuguese – as well as Mussismilia corals could be endangered, said Dutra, a biologist who has worked extensively in Abrolhos.

Flavio Lima, a professor of biology at the State University of Rio Grande do Norte in the north-east, said the oil could even prove fatal to the coral reefs.

“The coral is not an organism, it is a colony and it is very sensitive to alterations in the composition of nutrients,” he said. “Oil contamination could cause widespread death of coral colonies.”



Brazil’s coastal mangrove forests are important reproduction centres for many species of fish, Lima said.

“These mangrove areas are nurseries. We have the prolonged effects of the oil, that go from contamination of food sources like algae and invertebrates until [it reaches] the food chain … [The spill] also represents a risk for local populations who depend on crustaceans, like crabs and shrimp, and molluscs like oysters and clams, for survival.”

Facebook Twitter Pinterest A crab walks on oil spilled on Itacimirim beach, in the city of Camacari, Bahia state. Photograph: Mateus Morbeck/AFP via Getty Images

Brazil’s state oil company, Petrobras, said the oil came from three Venezuelan fields. Last Friday Federal Police and the Brazilian navy said an oil tanker flying a Greek flag and carrying crude oil from Venezuela was the main suspect after satellite images showed it was the only ship near an oil slick spotted 700km off Brazil’s north-east coast on 28-29 July, en route to South Africa.

Delta Tankers, owners of the Bouboulina tanker since identified by Reuters as the ship concerned, has denied responsibility. The ship “sailed from Venezuela in laden condition on July 19 2019 heading directly, with no stops at other ports, for Melaka, Malaysia, where she discharged her entire cargo without any shortage”, the company said in a statement.

In a Facebook Live event last Friday alongside Bolsonaro, the fishing and agriculture secretary, Jorge Seif Júnior, said there was no risk of contamination. “The fish is an intelligent animal. When it sees a blanket of oil, it flees,” he said.

Maurício Cardim, 42, who rents boats to tourists and researchers in Bahia, said the evidence on the ground proved otherwise.

“I have seen dead fish, I have seen jellyfish… I have seen an enormous quantity of seaweed we don’t see at this time of year, coloured with oil,” said Cardim, who is part of the Coast Guardians group of volunteers who are cleaning up the coast of Bahia state. “We want a solution. For now we are cleaning our beaches, because we live from the sea.”