Whale ears, shell oil, and the hidden toll of seismic surveys

Oil exploration off South Africa’s coast threatens to silence, subdue, and scatter the region’s marine life

Published March 6, 2022 8:29AM (EST)

The Liberian-registered oil tanker Goldway berths at Hound Point Oil Terminal on the Forth Estuary, as uncertainty continues in the global oil market as a result of the coronavirus (COVID-19) crisis (Ken Jack/Getty Images)
The Liberian-registered oil tanker Goldway berths at Hound Point Oil Terminal on the Forth Estuary, as uncertainty continues in the global oil market as a result of the coronavirus (COVID-19) crisis (Ken Jack/Getty Images)

This article originally appeared on Undark.

When I read last December that Shell had gotten a court's approval to commence seismic exploration for oil off the coast of South Africa, my first thought went to whale ears. Specifically, the wax that builds up in them.

Like humans, cetaceans — whales, dolphins, porpoises — produce ear wax, and in certain species, this wax, or cerumen, builds up over their lifetime. But unlike human ear wax, which can hinder our hearing by blocking airborne sound waves traveling in our ear canal, cetacean cerumen has almost the same density as the fluid — water — in which the whale swims. And while scientists still don't know exactly how whale hearing works for all species, the wax doesn't impede their ability to navigate their aural environment.

Back before commercial whaling was widely outlawed, plugs of earwax were frequently collected from whale carcasses and stored in archives. In much the same way that tree rings and Arctic ice cores capture Earth's climate history, the layers of wax that build up, year upon year, can illuminate the tale of a whale's life — from the pollutants in the waters of its youth, to its stress levels, to when it became sexually mature. As creatures that can live to be more than 100 years old (depending on the whale species and barring human intervention), whales carry a history of oceans in their ears — a history that vibrates with all the songs of their world, from krill devoured in great gulps to the oil spills of leviathan ships.

Shell's plans to explore for oil off of South Africa's eastern shore, near a region known as the Wild Coast, threatened to etch in the cerumen of so many whales a dark new chapter. The area includes the migratory routes and breeding grounds of several whale species, including humpbacks and southern rights. A seismic oil exploration operation would typically place, in those environmentally sensitive waters, a ship that points an air gun at the seabed and fires blasts every 10 to 15 seconds, for days, weeks, or months on end. The blast sounds, far louder than most non-human generated noises, can carry for tens to hundreds of kilometers. From the pattern of reflections of those soundwaves, one can map what lies beneath the seabed. If oil were found, Shell would likely drill down into those long-ago liquified remains of the life that went before, extract it, and pump it into today's world.

In response to pushback, Shell representatives contended that the surveys would contribute to South Africa's energy independence and provide jobs and, at the same time, that there is no evidence that seismic surveys do lasting harm to marine life. (The American Petroleum Institute maintains a page dedicated to explaining the safety and importance of underwater seismic surveys for oil exploration.) But if seismic survey operators benefitted from a dearth of environmental impact studies for many years, more and more research shows that marine life is silenced, deafened, subdued, and scattered by the major sonic impacts.

Studies have found, for instance, that whales tend to go missing in exploration areas and behave differently while surveys are underway. One study found that male fin whales stopped singing during surveys, potentially impacting reproductive rates. The disorienting effects of the seismic blasts can also impact smaller marine creatures, down to zooplankton, the foundation of the marine food chain. A 2021 study showed that even marine plant life can be adversely impacted by human-generated noise.

Similar proposals to do seismic surveys off the United States' east coast have been subject to a court battle since the Trump administration authorized the use of seismic blasting in 2018. While opponents argued that the surveys endanger not only wild marine spaces but the livelihoods of coastal communities, the exploration permits expired before the court reached a decision. Under the Biden administration, the future of offshore surveys and drilling remains unclear.

It's a coincidence that Shell received the go-ahead for seismic exploration right as the southern region of Africa had been designated the epicenter of a concerning new Covid-19 variant. The world's eyes were fixated on the omicron variant (which may or may not have originated in South Africa). A headline about a regional skirmish over oil exploration would have been easy to gloss over. That was great news for Shell.

But then, this news barely made a ripple in the first place. 

In some ways, Shell's determination to continue searching for oil off of South Africa is indicative of a commitment to business-as-usual for fossil fuel companies. The United Nations climate summit in Glasgow is long over. Though it attempted to align itself with the conference, the company did not have an official presence there. Nonetheless, many delegates from oil-producing states either worked or had previously worked closely with oil companies — and were thus indirect representatives for the fossil fuel industry. No one had time to talk about whales losing their songs to seismic surveys.

In December, less than a month after a judge gave Shell the go-ahead, another South African court ordered the company to suspend its underwater surveys along the Wild Coast. Shell threw in the proverbial towel and terminated its contracts with the survey vessel. But the threat of underwater seismic surveys didn't dissolve, it just momentarily submerged. A new seismic survey began on the west coast of South Africa in January. As with the December court interdict against Shell, this survey has also been temporarily halted — for the time being. This is a major success for Indigenous activists and environmental groups, but also an indicator of the tenacious commitment to fossil fuel exploration on the part of oil companies.

When it comes to fossil fuel exploration, there is no proposal so terrible for the planet that it actually dies forever. Until profound environmental justice regulations are adopted around the world, these projects will continue to resurface, zombie-like, from the depths. What stark chapters of oceanic history will these projects write in cetacean cerumen? What stories will be forever hushed within those floating cetacean ears? 

By P.K. Read


Related Topics ------------------------------------------

Climate Change Marine Marine Biology Oil Resource Extraction South Africa Undark