Written by Alan Barker, Freelance Writer, British Science Festival 

We know more about the surface of Mars than we do about the seabed on our own planet. And, just as we begin to discover the riches of this extraordinary environment, we’re planning to ruin it. Diva Amon is a marine biologist working to understand the deep ocean so that we might be able to manage it more effectively. Diva delivered the Charles Lyell Award Lecture at this year’s British Science Festival. Alan Barker took the plunge.

In Chapter 53 of his great work, the Naturalis Historia, Pliny the Elder wrote:

"By Hercules! in the sea and in the Ocean, vast as it is, there exists nothing that is unknown to us, and, a truly marvellous fact, it is with those things which Nature has concealed in the deep that we are the best acquainted!"

He went on to list 176 species.

Two thousand years on, we’re only just beginning to realise how short of the mark that number was. “There are likely to be about one million species in our oceans,” Diva Amon told us in the Charles Lyell Award Lecture at this year’s British Science Festival, “two thirds of which are unknown – and most of these are in the deep ocean.”

To date, Diva has added seven new species to that number. She’s working hard to develop a fuller understanding of this most unexplored of habitats.

The task is urgent.

The deep sea – everything from two kilometres down to 11 kilometres in the Mariana Trench – occupies over 60% of the ocean. It’s always been hard to get at; for most of us, it remains out of sight and out of mind. For the first hundred years of deep-sea exploration, we assumed that the very deepest parts of the ocean were cold and barren. After all, beyond 400 metres, the water is dark, freezing and under crushingly high pressures. What could survive?

In the last few decades, new technology revealed extraordinary answers. Using Remotely Operated Vehicles and submersibles, we’re learning – fast, but not fast enough – that deep ocean is the most varied habitat on the planet. Mountains and canyons give way to vast abyssal plains and lakes of brine. This vast ecosystem helps to regulate the climate by sequestering carbon and absorbing heat.

And life thrives.

Extreme conditions have bred extreme adaptations: gigantism and dwarfism are common; many organisms have evolved a high tolerance of extreme temperatures and chemical concentrations. And we’re learning from those adaptations. We’ve discovered enzymes that operate at low temperatures, allowing us to wash our clothes with less energy. Deep-sea sponges have inspired new fibre optic technology.

Life down there is slow. The only food available drifts slowly from the surface, so animals must conserve energy. Their metabolism is slow so they move slowly, and they grow slowly. Some sharks live for 400 years, some corals for almost 3,000. One glass sponge, Monorhaphis chuni, lives for 11,000 years – twice as long as man has had the wheel. The deep ocean doesn’t cope with change easily. If we start to interfere, recovery will take thousands of years.

And we are starting to interfere. We’re hungry for the metals to feed our desire for hi-tech devices, for batteries and for renewable technology: cobalt, nickel, copper, manganese, zinc, silver, gold, tellurium, vanadium – the list goes on. And the deep ocean promises to provide them.

Mining companies are looking for three principal types of deposit: polymetallic nodules, potato-sized accretions of metals sitting on the seafloor like cobbles; polymetallic sulphides, found at hydrothermal vents on mid-ocean ridges; and cobalt-rich crusts, located on seamounts. All three habitats are almost unimaginably diverse and perilously vulnerable.

Whatever the habitat, the mining process will be similar. Vast machines will scour the ocean floor and pump material to a surface ship. Wastewater will be released back into the ocean. The habitat directly in the machines’ path, will of course be destroyed – and will probably not recover for thousands of years. Plumes of sediment will drift tens of kilometres, vertically and horizontally, disrupting the critical food networks linking surface to ocean floor. Mining could impact our fisheries, and the ability of the ocean to produce oxygen. We shall almost certainly lose species before we’ve even discovered them.

The vast majority of the open ocean is international waters. The resources in those waters are designated ‘common heritage of mankind’: they belong to all of us, and to our descendants. So an intergovernmental body, the International Seabed Authority, related to the United Nations, has been established to regulate mining in these areas.

So far, the ISA has leased thirty plots of seafloor for mineral exploration. These areas are not small. Each plot is about 70,000 square kilometres – roughly the size of Scotland. And the prospectors will be commercial companies or state-owned enterprises.

As yet, no mining has begun. The ISA has yet to set the rules. The organisation meets twice a year at its HQ in Jamaica. All the relevant nation states are invited to attend, along with NGOs, industry representatives and intergovernmental bodies. But in truth, some states simply can’t afford to send representatives. Although 70% of countries on Earth have deep sea in their jurisdiction, but only 16% of those have the resources and tech to access it.

“We all have a stake in these decisions,” Diva told us, “but we don’t all have a voice.”

And the science informing this decision-making is itself not inclusive. “I’ve now been on 16 deep-sea expeditions,” she told us. “On none of these expeditions has there ever been anyone that looked like me, sounded like me or had similar experiences to me. I was the only person of colour, the only woman of colour, the only participant from a developing country.” (Diva is Trinidadian.) We treasure diversity in nature. Diversity brings resilience. Surely, Diva suggested, we should think the same way about deep-sea science and policy?

The questions we face are urgent and painfully difficult. Is it better to mine out of sight and out of mind? Should we damage habitats that can recover only on geological timescales? Are we trying to avert a human-induced planetary crisis by creating another one?

So, what can we do? Diva answered that question in her Q&A. First, we can become more knowledgeable. Follow the work of the Deep Ocean Stewardship Initiative, for which Diva herself works. Check out the live video links from the Okeanus Explorer, the  EV Nautilus, or the R/V Falkor.

Diva didn't mention this idea, but perhaps one of the most immediately useful actions is to recycle some of the estimated 40 million old gadgets we have stockpiled in our homes...

Alan Barker is a writer, trainer and coach specialising in communication skills. He has been working with the British Science Association since 2015. Alan’s webinar, Storytelling for Scientists, is on the 3M YouTube channel.