Just 30 of the prehistoric fish known to exist, raising fears oil wells will push it to extinction

This article is more than 2 years old

This article is more than 2 years old

Bright blue, older than dinosaurs and weighing as much as an average-sized man, coelacanths are the most endangered fish in South Africa and among the rarest in the world.

Barely 30 of these critically-endangered fish are known to exist off the east coast of South Africa, raising concern that a new oil exploration venture in the area could jeopardise their future.

Coelacanths, whose shape has remained almost unchanged for 420m years, captured world attention when the first living specimen was caught off the port city of East London in 1938. This discovery was followed by the subsequent capture of several more off the Comoros islands in the early 1950s, confirming that coelacanths were definitely not extinct.

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December 2000 brought further excitement when divers found a small coelacanth colony in underwater canyons near South Africa’s Sodwana Bay, adjacent to the iSimangaliso wetland park and world heritage site.

Now the Rome-based energy group Eni plans to drill several deep-water oil wells in a 400km long exploration block known as Block ER236.

Dr Andrew Venter, the chief executive of Wildtrust, one of several conservation groups lobbying for a significant expansion of South Africa’s protected ocean areas, said: “The Deepwater Horizon oil spill in the Gulf of Mexico in 2010 decimated fish populations – so if we had an oil spill off iSimangaliso it is very likely it could wipe out these coelacanths.”

The Sodwana coelacanths are about 40km from the northern boundary of the Eni exploration area and nearly 200km north of the first drilling sites, but Venter said oil spills spread far and swiftly.

His concerns have been echoed by the coelacanth expert Prof Mike Bruton, who said the fish are specialist creatures, sensitive to environmental disturbance.

Facebook Twitter Pinterest Staff at the National Museum of Kenya show a coelacanth caught by a fisherman on 21 November 2001. Photograph: Simon Maina/AFP/Getty Images

“Anything that interferes with their ability to absorb oxygen, such as oil pollution, would threaten their survival. The risk of oil spills or blowouts during exploration or future commercial production in Block ER236 is a source of serious concern.”

Last year, Eni commissioned a mandatory environmental impact assessment (EIA) but the scoping report makes scant mention of the potential threat to the Sodwana coelacanths.

Instead, the report suggested that coelacanths were unlikely to be found next to the first exploration wells.

Responding to fears the fish could be wiped out by leaks or undersea blowouts, the oil drilling company said: “Eni always applies the highest operational and environmental standards, which often exceed local compliance regulations.

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“Prior to any operation we undertake sensitivity mapping to identify sensitive offshore marine habitat which guide our planning. In addition to this, Eni would comply with all the requirements of the environmental management programme which is based on the outcomes of the impact assessment.

“Specialist studies have been conducted for both marine ecology and oil spill modelling scenarios and no specific threat has emerged in relation to this. The specialist study pertaining to accidental spillage modelling is currently being independently third-party peer-reviewed.”

Bruton said studies on coelacanths caught off the coasts of Indonesia and Tanzania showed that the remoteness of their habitat had not protected them from exposure to pollutants such as PCB and DDT, which had been used on land but had drifted over the sea on atmospheric winds and had accumulated up the food chain to the top predators, such as the coelacanth.

If oil were to be spilled in the ocean, Bruton feared the coelacanth colony could be destroyed. “The risk needs to carefully evaluated before this commercial venture has progressed too far and it is too late,” he said. “Oil spills do not respect the boundaries of marine protected areas.”