I discovered … new life on the bottom of the Southern Ocean

EMany things on the sea floor are amazing to me. When you think of Antarctica, you think of penguins, whales, sea and ice in a stark landscape. I love the charismatic megafauna, but there are so many other interesting things in Antarctica – life on the sea floor rivals that of the Great Barrier Reef.

The view above the surface is quite monochrome, but below the organisms are oranges, yellows, pinks – there is a coral that is psychedelic purple! Most tourists who go to Antarctica probably don’t know anything about the crazy, wacky communities on the sea floor – it all intrigues me. It’s an explosion of color, it really looks like an art gallery down there.

Video photo of Stylasterid lace corals, sponge, crinoids, brittle stars seen during a scuba dive in the Bransfield Strait, Antarctica — A dive in the Bransfield Strait, Antarctica, reveals Stylasterid lace corals, sponges, crinoids and brittle stars. Photo: Greenpeace

I found over a dozen new species on my trips to Antarctica, including many sea cucumbers, one of which is named after me. There is still so much to discover, but work is slow for the taxonomists, and funding is scarce. On the last expedition with Greenpeace in 2022, we came across a community of long, brittle fire hair that has yet to be described and may take years before it is truly classified.

I knew I wanted to be a marine biologist from the age of 15. I’m from Melbourne, and Australia has a long history with the Antarctic. I started volunteering at the local museum and was put to work on Antarctic sea urchins. I was hooked. Sea urchins incubate their young in a small pouch near their mouth. They can have dozens of babies around them. On one female I found 353 babies. It’s quite cute – but I don’t know that everyone will think so.

Susanne Lockhart at Windansea Beach in La Jolla — Lockhart has been studying Antarctic marine life for more than three decades. Photo: Ariana Drehsler/The Guardian

My fascination and drive started with the puzzle, and working out what is what. Sometimes you have these organisms with characteristics that were described 100 years ago, but they can be wrong (Antarctic sea urchin taxonomy is a mess). If a young person realizes that these old reverent scientists can be wrong – I found that convincing.

On my first expeditions in the 2000s, I joined research vessels looking at fish stocks – but that required trawling. I was there to look at all the bycatch that is of course destroyed in the process.

One day stands out to me. We struggled to get the trawl back on deck because the net contained spectacular sponges that must have been hundreds of years old. These glass sponges were like enormous vases. You could sit in them, they were so big – at least a good meter across. They are also home to so many other organisms, such as snake stars and ice fish that lurk inside. Once you lose the structure these organisms provide, you mess with the entire ecosystem. But if you’re going to get it protected, you need to know it’s there and in those days that was the only way to do it.

Hexactinellid glass sponge — A glass sponge ‘like an enormous vase’ found in the Weddell Sea, Antarctica. Photo: Marizilda Cruppe/Greenpeace

Then, thanks to developments in technology, we can start looking at these communities in submarines, which is non-invasive, and you can see the whole thing in situ, which I much prefer. My first trip to the Antarctic seabed was in 2018.

You are dropped into the water in what is essentially a small bubble. It can take up to 30 minutes to reach the seabed. As you go down the light disappears – there is a point where you no longer see the light from above, and then all these bioluminescent animals start flashing before your eyes. An animal that might look like a gelatinous blob out of the water is revealed to be delicate, graceful and remarkable in the water when alive. Then you get close to the seabed and you turn on the lights and it’s an explosion of color – it’s just specular.

Dr Susanne Lockhart and John Hocevar, Greenpeace USA's Oceans Campaign Director and submersible pilot, in a red submersible surface in Antarctica. — Lockhart, left, with John Hocevar, Greenpeace USA’s oceans campaign director – and underwater pilot. Photo: Marizilda Cruppe/Greenpeace

My job is to discover what’s there and make a scientific case for protecting a site. Essentially, I’m looking for animals that are fragile and long-lived, and that won’t recover easily if damaged by fishing gear – things like coral and sponges that aren’t mobile and provide shelter for other organisms.

I helped create 47 vulnerable marine ecosystems (VMEs), which equates to more than 500 sq km of seabed now protected forever from commercial bottom fishing. The presence of VMEs helps us make a case for creating marine protected areas (MPAs) in the Southern Ocean around Antarctica. It’s a bit of a geopolitical quagmire, where some countries, namely Russia and China, don’t agree and so they block everything. We need a change in the political arena so that we can create more MPAs and this requires more public awareness of how special these places are.

At least once every expedition I will see something that really amazes me. Without a specimen in my hand, I won’t even know what phylum it is in (it’s the one below kingdom). It’s always pretty exciting.

I feel great responsibility. I have a unique and rare experience of witnessing one of the world’s last great wildernesses and I must share it. I would love for people not only to think of the penguins when they think of the Antarctic.