The Twilight Zone of the ocean

26m
Every day, untold numbers of strange organisms rise from the middle of the ocean to its surface. They may be playing a crucial role in slowing climate change, so scientists are struggling to understand this migration ... before it’s too late.
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Transcript

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Speaker 13 I'm Eliza Barkley, Fox's Science, Health, and Climate Editor. This April, our podcasts are teaming up to cover some of the most important issues threatening life on Earth.

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Speaker 16 The time today.

Speaker 16 Right now. The place, the ocean.
Hundreds of miles from any shore.

Speaker 17 So why don't we start at the top?

Speaker 16 Simon Thorld, age 57. Occupation ecologist, and today, guide.
He's taking us beneath the waves.

Speaker 17 So you can imagine that we're descending down and we look up and we can see the surface, right? We can see light coming down from the surface.

Speaker 16 But as we descend further and further, it's starting to look pretty dark.

Speaker 17 And then the switch really is when we go below 200 meters and now there's almost no light from the surface.

Speaker 16 The waters are deep and heavy. and cold.
But there is still a kind of light.

Speaker 17 We're seeing

Speaker 17 to the side of us or beneath us.

Speaker 16 Light from creatures glowing in the dark.

Speaker 17 A fireworks display of luminescence that is allowing these different organisms to communicate with each other or to avoid predators.

Speaker 16 Flash, a lantern fish, bedazzled with sparkling cells. Flash, a chain of connected clones known as a siphonophore, glowing green or blue or red like a string of holiday lights.

Speaker 16 Flash, an anglerfish dangles one bright bulb in front of its face to distract from the gaping mouth full of needle-shaped teeth.

Speaker 17 So we're still seeing fish and we're still seeing crustaceans like krill and we're still seeing jellyfish, but now this particular fish species we're talking about are not looking like anything that we've ever seen before.

Speaker 16 This is a dimension as vast as the ocean and as timeless as infinity.

Speaker 16 It is the ground between light and shadow, between science and mystery, and it lies between the pit of a man's ignorance and the sum of his knowledge.

Speaker 17 It is an area which we call the Twilight Zone.

Speaker 16 I'm Noam Hasenfeld here with reporter Bird Pinkerton. And don't worry, this is still unexplainable.
We didn't suddenly become a podcast about the Twilight Zone.

Speaker 3 We kind of became a podcast about the Twilight Zone.

Speaker 16 The Twilight Zone of the Ocean.

Speaker 3 Yeah, so this is the mesopelagic zone of the ocean. It's just a very fancy way of saying the middle of the ocean, the middle depths from 200 meters down to about 1,000 meters down.

Speaker 3 And it's known as the Twilight Zone because it's where sunlight kind of fades away.

Speaker 3 And also, it's very mysterious.

Speaker 14 It's almost easier to define it by what we don't know than by what we do know.

Speaker 3 And Doni Lavery has been studying the Twilight Zone for years now.

Speaker 14 And what really got me interested in the ocean Twilight Zone was just the vast uncertainties.

Speaker 16 Is the Twilight Zone more mysterious than the bottom of the ocean?

Speaker 3 Yeah, actually.

Speaker 3 Mostly because scientists only started exploring it fairly recently. Like for a long time, they thought of the middle as just kind of the water you had to get through on the way to the bottom.

Speaker 3 And they didn't really realize that the Twilight Zone itself was worth exploring until around World War II,

Speaker 3 when the U.S. started making a bunch of new naval equipment.

Speaker 16 Man developed clever new listening devices, devices that could hear a submarine underwater.

Speaker 3 They were using sonar, which emitted a pulse of sound.

Speaker 16 A pulse of sound sent out from a speaker located in the ship's hull.

Speaker 3 And this pulse of sound would travel through through the ocean and whenever it hit a target, some part of that sound would be reflected back up so they could measure it.

Speaker 16 Now man had a way to see for great distances beneath the ocean's surface.

Speaker 3 As part of the war effort, the Navy was sending out researchers to kind of refine these listening devices.

Speaker 3 I couldn't find any tape of the actual researchers doing this, so instead, I used some Twilight Zone clips to kind of fill in the gaps.

Speaker 16 Contact Bearing 280-1100 yards.

Speaker 3 Our Twilight Zone researcher, Andoni, says the scientists were doing their thing.

Speaker 14 Do you hear it, sir?

Speaker 3 They were sending out their pulses and measuring the reflections.

Speaker 14 Now, typically the strongest reflection in the ocean, the strongest reflector of sound, is the bottom. You see the bottom.

Speaker 14 But what they also saw were these shadow, like these additional reflections, which they couldn't quite explain.

Speaker 16 What am I listening to? They looked like false bottoms. Ghost, man.
Ghost.

Speaker 16 What exactly are false bottoms?

Speaker 3 So these were sonar readings that looked like the bottom of the ocean, but they were way too high up to be the bottom of the ocean.

Speaker 16 I want dead quiet all over the ship.

Speaker 3 So they were essentially picking up thick layers of something.

Speaker 14 And it turns out that as the day and night changed, these false bottoms migrated up and down in the water column.

Speaker 3 The false bottoms were rising and falling every day. They want us to be quiet so they can listen to it.
What I want to know is, listen to what?

Speaker 16 Yeah, listen to what?

Speaker 3 Well, so eventually researchers realized that if this bottom was moving, it was probably organisms. Okay.

Speaker 3 But like a lot of organisms, like so many so thickly packed together that they gave the impression of the bottom of the ocean. Okay, okay.

Speaker 3 Which meant that potentially they were witnessing like the biggest migration on the planet happening every single day.

Speaker 3 Like like countless organisms organisms coming up from the twilight zone, coming to the surface, and then sinking back down into the depths.

Speaker 16 Are these like

Speaker 16 fish? Are they big fish? Small fish? Bacteria?

Speaker 3 They have the same question.

Speaker 14 It was pretty definitely biological in origin, but just because it's biological in origin doesn't tell you a whole lot about what it actually is.

Speaker 3 So for decades now, researchers like Andoni have been using nets, sonar, they've been throwing cameras down there, but they still don't really know the basics.

Speaker 3 They've gotten samples from nets to give them ideas, but they don't know exactly how many organisms there are or exactly what they're up to.

Speaker 14 These organisms are often tiny organisms. They're traveling the equivalent of thousands and thousands of body lengths just to get up those few hundred meters, right? So why would they do that?

Speaker 14 How many of them do that? Do they do it every night? Do they get tired and decide, hey, I'm not doing it tonight? We don't know, right?

Speaker 16 So we don't really know anything.

Speaker 3 Yeah, I mean, no,

Speaker 3 it's not like these researchers are bad at their jobs.

Speaker 3 But the Twilight Zone is very hard to study.

Speaker 14 It's deep, it's dark, it's elusive, it's temperamental.

Speaker 3 So it's very hard to get sort of a full coherent picture here.

Speaker 3 That being said, they have learned a lot.

Speaker 3 They've found the weird, wonderful animals like the ones we heard about at the top. So like the anglerfish, for example.

Speaker 16 Are the anglerfish the ones with the like thing sticking out over their head with the light bulby thing?

Speaker 3 Yeah.

Speaker 3 You may be more familiar with it as like the terrifying sea creature in Finding Nemo. Of course.

Speaker 3 Where I get most of my fish knowledge from.

Speaker 3 Parts of that movie are very biologically accurate.

Speaker 3 But anyway, so scientists are finding cool creatures. And

Speaker 3 they're finding something else, something that's arguably even more important. They're finding that these creatures might be playing a really important role in slowing down climate change.

Speaker 14 The ocean is a really important vector for sequestering carbon.

Speaker 16 Sequestering carbon, meaning like absorbing CO2?

Speaker 3 Yeah. So Andoni was telling me that the ocean actually absorbs billions of metric tons of carbon dioxide from the atmosphere every single year.

Speaker 16 And this absorption is actually being done by the organisms, these migrating organisms?

Speaker 3 Kind of, potentially.

Speaker 3 They play a role in it. Sure.

Speaker 16 Okay.

Speaker 3 So the theory here is you have all this phytoplankton living at the surface of the ocean. It's just floating around up there.

Speaker 3 And as carbon in the air gets absorbed into the surface of the ocean, this phytoplankton uses it to make little shells for themselves or little plant bodies. And then

Speaker 3 all of our organisms come from the deep in the twilight zone. They're coming up at night and they're gobbling gobbling

Speaker 3 all of this phytoplankton up and then sinking back down again, taking their carbon with them.

Speaker 16 Okay, wouldn't they just bring the carbon back up with them the next night?

Speaker 3 No, because they're pooping. Pooping.

Speaker 14 Yes, that is correct. I have the pleasure of having a job where I can say pooping with a serious face.

Speaker 3 Andoni actually paints one of the prettier pictures of poop I've ever heard.

Speaker 14 It's marine snow. It's like the glimmer of stars in the sky.

Speaker 16 So it's like a beautiful snow globe of poop.

Speaker 3 Yes, the Twilight Zone, a beautiful snow globe of poop.

Speaker 16 And how much carbon, how much CO2 is being trapped in this marine snow?

Speaker 3 That's another question that we don't yet know the answer to. One source I read suggested that it could be double what all the automobiles in the world are pumping out every year.

Speaker 16 Wait, wait, double all the cars?

Speaker 3 Yes, but again, it's still just a possibility.

Speaker 3 Scientists like Andoni don't have a definitive number because they still don't know enough about the organisms that are pooping out this carbon in the first place.

Speaker 14 And we can't understand how important the mesopelagic is to the carbon cycle until we have a pretty good idea of how many, what kind, how big, what they eat, when do they migrate.

Speaker 14 These are fundamental to that question.

Speaker 16 Okay, so the Twilight Zone is this vast, mostly unexplored sort of middle depth of the ocean. Correct.

Speaker 16 And it seems like there's tons of these organisms coming up from the Twilight Zone, eating phytoplankton every day at the top, migrating back down, pooping it out. Potentially.
And that

Speaker 16 potentially. And that is

Speaker 16 potentially

Speaker 16 sequestering tons and tons of CO2

Speaker 16 and maybe helping mitigate climate change.

Speaker 3 Yes, that is the theory.

Speaker 3 And then in 2014, that theory becomes even more important.

Speaker 16 What happens in 2014?

Speaker 3 A scientist published a paper. And it basically said, hey guys,

Speaker 3 we took measurements, like sound measurements all around the world. And we think maybe the Twilight Zone has 10 times as many fish as we previously suspected.

Speaker 16 10 times?

Speaker 14 10 times. That's a lot.

Speaker 16 And I assume they must have missed all these fish because the Twilight Zone is really hard to study. Yeah, like

Speaker 3 I can't emphasize this enough. It is very big and very inaccessible.
And to be clear, they don't even know if this number is correct. It's a rough estimate.
There could still be problems with it. But

Speaker 3 the idea, the idea that they'd missed 90% of fish and who knows how many other organisms, this was essentially like a big and inspirational kick in the pants.

Speaker 14 I would even go so far as to say it was seminal. Seminal in as much as I think it really got people's imagination going.

Speaker 16 Yeah, I mean, it's like an entire ocean of fish we didn't know about before.

Speaker 3 But that ocean of fish, it doesn't just get researchers' imaginations going.

Speaker 3 So fisheries also get interested.

Speaker 16 Oh, because I guess they got 90% more fish that they can fish, right?

Speaker 3 Yeah, and these are not like fish for your plate. They're very bony and small.
But they are potentially good for, say, chicken feed or aquaculture. And this isn't just a theoretical thing.

Speaker 14 There are actually a few countries that have already been issued permits for fishing, the mesopelagic.

Speaker 3 So it's all small scale now, but if these twilight zone organisms are helping sequester billions of metric tons of carbon dioxide every year, like if this is a foot on the brink of climate change, we don't want to accidentally fish too much and mess that up.

Speaker 14 Suddenly, scientists woke up and they said, hey, we have this opportunity to understand what's happening in this ecosystem before we exploit it.

Speaker 3 And now there's kind of like this ticking clock.

Speaker 3 So Andoni and a bunch of other researchers at the Woods Hole Oceanographic Institution, they've gotten a ton of funding and they're doing all kinds of research to understand this ecosystem.

Speaker 3 Some of them are testing little bits of tissue and poop left behind in the water. Other people are studying what is what, looking at at currents.

Speaker 3 And Doni's team has got kind of like a dolphin noise machine.

Speaker 14 What we do is we transmit sound.

Speaker 14 Let me see if I can do it.

Speaker 16 Okay, so all of this is gonna hopefully help them understand everything about these organisms, like what they are, why they're migrating, how much carbon they might be absorbing before this ticking clock runs out.

Speaker 3 Right, but it doesn't end kind of with the science coming out of this Woods Hole team, right?

Speaker 3 Like to protect the Twilight Zone and to fish it sustainably, people also have to use this science to change policy.

Speaker 14 And I've found that changing policy is harder than changing science.

Speaker 16 Harder than exploring the Twilight Zone?

Speaker 3 Very potentially.

Speaker 3 I'll tell you more about it in a sec.

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Speaker 16 Bird, we're back. Yes.
Before the break, you were talking about how we need to make sure we don't overfish the Twilight Zone, because if we do, it might speed up climate change.

Speaker 16 So how do we protect the Twilight Zone? Like, who controls the ocean?

Speaker 3 It's complicated.

Speaker 15 More than two-thirds of the ocean is actually beyond the jurisdiction of any one state.

Speaker 3 I spoke to a lovely researcher. Her name is Harriet Hardin-Davies.
She spends a lot of her time figuring out sort of how ocean science becomes ocean policy.

Speaker 3 And she basically told me that there are lots of different organizations that are regulating some things, other things aren't regulated at all. And what you end up with is a patchwork.

Speaker 15 So we do have some complexities in the ocean governance framework, as well as some gaps.

Speaker 3 Which means that Twilight Zone researchers could come up with the most solid scientific evidence in the world, like a very clear case that fishing shouldn't happen in one area or another.

Speaker 3 But it's very hard to actually translate that evidence into the law of all the ocean there's no one place

Speaker 15 that you could take that to and where the actors there would be empowered to do something about it

Speaker 16 so so is all this research for nothing are these researchers just like yelling into the void no

Speaker 3 not the void

Speaker 3 okay it's more like they're yelling to lots of different organizations, each with very limited power and reach.

Speaker 3 But that's why there are actually currently some really cool ideas being floated about how we might change things.

Speaker 16 What kind of ideas?

Speaker 3 So there's one model for making things less patchy kind of tucked away in existing sea law.

Speaker 3 So for just some context here, for a long time,

Speaker 3 the laws of the ocean were even more of a free-for-all than they are now.

Speaker 15 For years, decades, centuries even, the idea of something called the cannon shot rule prevailed, which is exactly as it sounds.

Speaker 15 People thought, well, if I can shoot a cannon from here offshore, then that's how far I can control.

Speaker 3 And then in the 1960s, 70s, 80s, post-World War II, Cold War is going on, international collaboration is the rage.

Speaker 3 And the countries in the UN are like, okay, these cannonshot laws, not going to cut it anymore. We got to get something better on the books.

Speaker 3 And near the beginning of all these conversations and debates, the Maltese ambassador, this guy named Arbid Pardo, gets up to speak.

Speaker 15 And I can see his face now. He's got short grey hair and glasses, and he stands off at the United Nations and delivers this, it was quite a long speech.

Speaker 3 And in this long speech, Pardo talks about the ocean floor, so the seabed. And he says, look, the ocean floor has a lot of potential for mineral wealth.

Speaker 15 He's saying that that was too great for any one nation to have, and it was also also not fair that only a few nations would benefit from this space that was shared by all.

Speaker 15 And so he argued that the seabed area should be considered as the common heritage of mankind.

Speaker 16 The common heritage of mankind?

Speaker 3 Yeah. So this is the model that might interest us.
It eventually becomes policy for the seafloor.

Speaker 3 So anyone who wants to use the seafloor anywhere on the ocean, They have to make sure they're sharing the wealth and splitting up resources equally.

Speaker 3 So there's this one group, the International Seabed Authority, that makes sure they do that, which means there is one body that controls all the seafloor that's under international waters.

Speaker 16 Okay, so in this case, if you're a researcher and you're studying the seafloor, you actually have somewhere to go with your research if you notice that something really needs to happen with the seafloor.

Speaker 3 Yeah, exactly.

Speaker 15 It is one forum where science can provide really important inputs to policy.

Speaker 16 But this is just the seafloor, right? This isn't the twilight zone?

Speaker 3 Right. So originally, Pardo and his colleagues did want it to cover all the ocean, bottom to the top, including the twilight zone.
And they kind of had to settle for just the seafloor.

Speaker 3 But if our big problem here is that it's hard to convert science into policy because there isn't one place to go for the whole ocean, maybe they could expand this model.

Speaker 16 Yeah, they just need to take it from the bottom of the ocean and bring it up to the rest of the ocean.

Speaker 15 Right.

Speaker 15 So it's a really exciting year for this.

Speaker 15 At the moment, states at the UN are negotiating a new treaty. This treaty is fondly referred to as the BBNJ Agreement.
And if acronyms aren't allowed, we'll just call it the High Seas Treaty.

Speaker 16 The High Seas Treaty.

Speaker 3 Yes, this is a brand new treaty. They've been debating it for years now.
And if it comes together, it will cover more than just the seafloor, right?

Speaker 3 It will cover the ocean from top to bottom, including the Twilight Zone.

Speaker 3 One small thing to note here is that some parts of Pardo's seafloor principle, so this common heritage of mankind, like for example, the part where all the minerals in the seafloor are split up equally, that might not happen here.

Speaker 3 But the idea is we're going to come away with a treaty that makes ocean policy less of a disconnected, confusing patchwork.

Speaker 16 Okay, so it might be slow, frustrating, but there's at least like potential here, right? Like a glimmer of hope.

Speaker 3 Yes, there's a lot to be hopeful about. I always love to be hopeful.
But I think what I learned from this conversation with Harriet is that

Speaker 3 it's important not to just sort of be blindly hopeful when it comes to ocean science.

Speaker 15 So, some people might say that the more we know about the ocean, the more science we have, the more we'll protect it, or the more informed decisions will be made.

Speaker 15 But I mean, that in itself is a hypothesis.

Speaker 3 Ocean research is the best. It is wonderful.
I am all for it.

Speaker 18 Harriet is all for it.

Speaker 3 But a study on the number of fish, for example, can inspire scientists or it can inspire fisheries. Science is just the first step here.

Speaker 15 But ultimately, it depends on how ocean science is used in ocean policy. It depends on who's in power and how that power is used.

Speaker 18 This episode was produced and reported by Bird Pinkerton. We had editing from Noam Hessenfeld, Julian Weinberger, Brian Resnick, and our senior producer, Meredith Hodenot.

Speaker 18 Noam handled the music, and Christian Ayala did the mixing and sound design, with some key pointers from Afim Shapiro, who also did a great rod-serling impression for our intro.

Speaker 18 Fact-checking and extra help from me, Mandy Nguyen.

Speaker 18 Special thanks this episode to Annette Annette Govindarajan, K.R. Baltese, and Suzanne Pelison from the Woods Hole Oceanographic Institution for all their help.

Speaker 18 And thanks to Amanda Northrup, Lauren Katz, and Liz Kelly Nelson, the VP of Vox Audio.

Speaker 18 If you want to see pictures of weird Twilight Zone creatures, or if you want to learn more about international ocean policy, sign up for our newsletter.

Speaker 18 This week it's got an article on the Twilight Zone from Bird and links to a lot of articles by Harriet. You can sign up at Vox.com slash unexplainable, or you can find the link in our show notes.

Speaker 18 This episode is part of Earth Month at Vox. For more podcasts related to the environment, check out Today Explained, Worldly, The Weeds, Vox Conversations, Future Perfect, and more.

Speaker 18 You'll find episodes about electric cars, carbon removal, clean energy innovation, and nuclear energy. As for our show, feel free to send us your thoughts.

Speaker 18 We're at unexplainable at vox.com, and we try to reply to every email.

Speaker 18 Unexplainable. It's a part of the Vox Media Podcast Network and we'll be back in your feed next Wednesday.

Speaker 16 Everybody's afraid.

Speaker 16 Everyone, Dad, why?

Speaker 16 People are afraid because they make themselves afraid.

Speaker 16 They're afraid because they subvert every great thing ever discovered, every fine idea ever thought, every marvelous invention ever conceived. They subvert it, Jodie.
They make it crooked and devious.

Speaker 16 Then, too late.

Speaker 16 Far too late, they ask themselves the question, why?

Speaker 16 Then it's too late. Everything is too late.

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