Deep-sea dives akin to being in a Star Trek adventure: Ecologist Jon Copley

Copley was on the first manned mission to Earth’s deepest-known hydrothermal vents, in 2013. He’s been on 20 deep-sea expeditions in all. Here’s what it feels like, what it takes, and why he does it.

It’s been just over 80 years since Man began to explore the seabed at depths beyond 1,000 metres. There have now been deep-sea explorations to nearly 11,000 m, within the Mariana Trench (the bottom of which constitutes the deepest known point on Earth).

‘Studying life in deep-ocean environments has given us clues to some of the big questions in biology, such as how life might begin on a planet,’ Copley says. (Image courtesy University of Southampton)

It is at these depths that the strange creatures that now typify the dark deep in the popular imagination were uncovered. With no light, temperatures usually just a few degrees above freezing, and crushing levels of pressure, some of the creatures at these depths carry their own little lanterns in front of their faces (powered by special light-producing organs called photophores), others have no vision, some are entirely transparent. And all have bodies and organs equipped to deal with the crushing pressure.

Among those who have seen these creatures up-close is Jon Copley, a marine ecologist at the University of Southampton. He was on the first manned mission to Earth’s deepest-known hydrothermal vents, in the Cayman Trough, 5 km or 5,000 m below the surface, in 2013. He’s been on 20 deep-sea expeditions in all, investigating undersea hot springs, a brine lake at the bottom of the Gulf of Mexico, and underwater mountains around Antarctica.

Each dive takes years of planning and preparation, he says. Aside from coordinating with scientific and engineering teams and applying for diplomatic clearances to work in international waters, which can take months, you need to put together a team of scientists that can help you make the most of each opportunity.

“When it goes well, it can be exhilarating,” Copley says. “But if it goes wrong, it’s incredibly frustrating, as you usually only get the one chance of that expedition to get things right.” Still, there’s no job he’d rather have. “It’s as close to a Star Trek adventure as we’re likely to get for a few centuries,” Copley says. Excerpts from an interview.

* How far back does this kind of exploration go?

Around 1938, (American researcher) Maurice Ewing led a team that built a camera rig that took photographs of the seabed at nearly 5,000 metres, probably the first photographs of the deep ocean. Others developed similar systems in the 1940s and 1950s, and their photographs started to show the varied nature of the seafloor and its inhabitants, and prove that it was not the featureless and lifeless flat plain of grey mud down that it was thought to be.

Perhaps the most influential early deep-sea photographs were by (explorer and filmmaker) Jacques Cousteau and his team in 1959, when they lowered their Troika camera sled several thousand metres from their ship Calypso in the middle of the Atlantic Ocean. Cousteau’s photographs confirmed the existence of an undersea rift valley there, with steep rocky cliffs. This was vital evidence for the theory of plate tectonics, which revolutionised the understanding of our planet’s geology in the 1960s.

The extent of life in the ocean’s depths is amazingly lush, Copley says, from pale sea anemones to (below) giant squid in vibrant hues. (Image courtesy University of Southampton)

. (Image courtesy University of Southampton)

* How much of the deep ocean has been explored, either remotely or through dives?

The area of deep ocean floor that has been seen by human eyes, either peering through the portholes of human-occupied vehicles, or from remotely operated vehicles and cameras, is quite small. It’s probably less than one two-hundredth of one per cent. And that’s just the ocean floor. The vast volume of water above it, forming the interior of the ocean, is even less investigated.

* What dives have been the most memorable for you?

The colonies of animals that live around undersea hot springs are spectacular, and different species live at the undersea hot springs in different oceans, so each of those sites is special to explore. The brine pool, a lake of ultra-salty water at the bottom of the Gulf of Mexico, is an eerie, almost spooky environment, which feels very different to those hot springs. The life on undersea mountains around Antarctica is different again, with an amazingly lush carpet of life covering the sea floor at 1,000 metres deep.

* What are some of the unique adaptations you have seen in living things at these depths?

The trials of life are the same everywhere: the challenges of finding food, avoiding being eaten, and finding a mate to reproduce with. The solutions to those challenges are what’s different to what we’re used to.

In some deep-sea environments, food can be scarce, so some predator species such as viperfishes have huge teeth and jaws. Other deep-sea species can make a meal of things that other animals can’t digest, such as zombie worms that secrete acid to dissolve the skeletons of animals that have died and sunk to the ocean floor. In some deep-sea environments where life is sparse, anglerfish males, for instance, become small parasites on the females, dangling from their partner, ready to fertilise her eggs when she spawns them.

* What are the deep seas teaching us about how the world works?

Most of the geological processes that shape our world also happen in the deep ocean, from undersea volcanoes and volcanic rifts to ocean trenches where the plates of the Earth’s crust collide. Studying life in deep-ocean environments has also given us clues to some of the big questions in biology, such as how life might begin on a planet. Then there are spin-offs from ocean exploration for our everyday lives. Just like space exploration gave us non-stick pans, ocean exploration is helping design better fibre-optic cables, from studying the glass skeletons of deep-sea sponges. In medicine, new therapies for conditions such as some types of prostate cancer are being developed based on some of the adaptations of deep-sea microbes. There is so much more that we could learn from the ingenuity of nature in the deep ocean, which is why we need to continue to explore it, and protect it from human impact.