Far below the surface of the ocean, off the coast of eastern Australia, is an area simply known as "the abyss." The largest and deepest habitat on the planet, the abyssal zone stretches well beyond Australia's waters and spans half the world's oceans — but it remains largely unexplored.
Marine biologist Tim O'Hara recently set out change that, on a monthlong expedition with about two dozen scientists from seven countries. The voyage dredged up hundreds of previously unknown species along the way.
All Things Considered's Ari Shapiro spoke with O'Hara via satellite phone on his final day aboard the research vessel Investigator.
"It is really a voyage of discovery," O'Hara says. "It's kind of amazing in the 21st century that you can still do that, but yes you can!"
The team has been sending equipment down to depths of 4,000 meters, or about 13,000 feet, to scrape along the bottom of the sea floor and collect creatures who call the abyss home. It's a tough ecosystem to live in, O'Hara says.
"It's a place of crushing temperatures and no light and very little food," he says. "One of the great extreme environments of the planet."
Among the notable finds of the month was a "faceless fish" that hadn't been documented in the waters of Australia since 1873. The eel-like fish has a mouth on the bottom of its body and eyes buried deep underneath its skin. It sucks up crustaceans and other tiny sea creatures off the bottom of the ocean floor, O'Hara says.
The team has been working 12-hour days for 31 days straight, bringing up hundreds of other species that have been meticulously sorted, photographed and documented. O'Hara estimates that over a third of the animals they've collected are previously unknown, but says it will probably be a couple of years before they can catalog them all.
"Some people are a bit disturbed that we go in there and we're actually bringing animals back to the surface to look at, but really science demands that," O'Hara says. "We really need to see animals in detail, we want to see the DNA, we need to bring them to the attention of people — otherwise it's just another hidden world."
And although the world they are exploring has never been touched by humans, there's still plenty of signs of human life from above — in the form of trash and microplastics.
"Every single net that we put down there picked up some rubbish: paint cans, old fishing wire, bottles," O'Hara says.
The Investigator completed its voyage of discovery Thursday. Next, the scientists will will begin the task of researching and preserving their findings on dry land.
But first, O'Hara says he's ready for a drink.
"It's a dry ship, so we don't get to drink at sea," he says. "We're having a 'retox' when we get back to shore."
ARI SHAPIRO, HOST:
We're going to speak now with someone who has spent the last month exploring a largely uncharted world, discovering some bizarre creatures that have never before been seen by humans. Dr. Tim O'Hara is a marine biologist, and we are calling him on board the research vessel known as The Investigator. Dr. O'Hara, welcome. And tell us where you are right now.
TIM O'HARA: Hello, Ari. Right now we're in the Coral Sea, which is an area off northeast Australia. People probably familiar with the Great Barrier Reef - and we're about 100 kilometers offshore of the Barrier Reef. But this is our final site. And after this, we head to Brisbane and home.
SHAPIRO: The Barrier Reef is relatively shallow. You have been exploring quite the opposite, someplace very, very deep.
O'HARA: That's right. That's right. Most people think of the sea as something that's surrounding the coastline. And perhaps if you're a scuba diver, you dive down to 50 meters. But we've been surveying 4,000 meters beneath the sea. So that's two nautical miles straight down. So it's very deep. It's a place of crushing temperatures and no light and very little food. And it's kind of one of the great extreme environments of the planet.
SHAPIRO: And yet, despite those extreme temperatures and pressure and darkness, you have found extraordinary things down there. Tell us about it.
O'HARA: Yeah. There's lots of amazing things. I mean, it's a completely different environment that demands different things of the animals. There's not a lot of food, so that means everything's kind of long and jelly-like in a lot of ways. A lot of the fish look like eels. And that's because they don't need as much magical energy to function. And a lot of animals just stay still for long periods, just waiting for prey to come along.
SHAPIRO: You've been doing this research for the last month in this abyss. How many new species do you figure you've discovered in that time?
O'HARA: Well, you know, that's going to take another couple of years to kind of give you a precise figure. But, you know, I think a good rule of thumb is at least a third of everything we see would be new.
SHAPIRO: Is that, like, dozens or hundreds or what?
O'HARA: Yeah, it would be hundreds.
SHAPIRO: Hundreds of new species just in the last month.
O'HARA: Yeah, easily. You know, we haven't explored this environment much in the Southern Hemisphere at all. And around Australia, this is really the first dedicated trip to study the abyss. So it is really a voyage of discovery. It's quite amazing in the 21st century you can still do that. But, yes, you can.
SHAPIRO: I've been following along on your blog, where you have videos and photos. And there are more extraordinary creatures there than I can count. Will you tell us about one of your favorites?
O'HARA: Sure. I mean, I actually study a group of animals called brittle stars. And, believe it or not, they dominate the deep sea, and yet hardly anyone's heard of them. So kind of they're my sentimental favorite.
O'HARA: But, you know, there's been lots of other amazing animals, the crustaceans. You know, they've got extraordinary spines all over the bodies. And lots of the worms have petal and hair-like structures all over them. And then there's the fish, as well. They're always the outstanding favorites - you know, the tripod fish, which are sitting on three kind of processes coming from their fins like a camera on a tripod. We've had faceless fish. It's a fish that almost has no eyes. The eyes, perhaps, are very deep. No one's really quite sure, but...
SHAPIRO: Because when you're in the pitch-black depths of the ocean, why would you need eyes?
O'HARA: Exactly, exactly.
SHAPIRO: And so the mouth is on the underside of its body, so it has, really, no eyes. This is why it's called the faceless fish.
O'HARA: That's right because, really, you look at the thing, and it's just kind of a round end for the animal. The mouth is underneath. And what it uses it for is sucking. So it would go along the sea floor, sucking up little worms and crustaceans and shells and that sort of stuff.
SHAPIRO: Describe what you're actually doing to get these creatures.
O'HARA: So we're relying on a good, old-fashioned, you know, metal box on the end of a very, very long rope. We have video cameras that we take down. We also have small nets to take some fish and other sort of invertebrates from the sea floor. Some people are a bit disturbed that we go in there and we actually bring the animals back to the surface to look at. But, really, kind of science demands that we really need to see animals in detail. We want to see the DNA. We need to sort of bring them to the attention of people. Otherwise, it's just another hidden world.
SHAPIRO: When we're talking about hidden worlds like this, it's easy for the imagination to run wild. Is there any chance that the collection techniques you're using would miss the leviathans, the fast creatures, a type of species that might not be caught in your net?
O'HARA: Yeah, sure, the megalodons. Yeah.
O'HARA: I mean, all those things - yeah, absolutely. You know, our nets and sleds are very small. So, yes, anything big, smart and intelligent would just move easily out of the way. And you've got to pitch it down. You know, it's an area completely without lights. No sunlight can penetrates that far. And, you know, our cameras go down there - and this huge ball of kind of iridescent light. To a deep-sea creature, we're the aliens, really. I'm sure the intelligent ones just swim out of the way. So, yes, maybe. Maybe there's that big monster just waiting out there. Who knows?
SHAPIRO: Well, Dr. O'Hara, congratulations, and thank you for telling us about the expedition.
O'HARA: And thank you for having me.
SHAPIRO: Dr. Tim O'Hara is wrapping up his month-long exploration of the abyss off Australia's eastern coast. Transcript provided by NPR, Copyright NPR.