A magical world at the ocean’s edge

12:44Rebecca Johnson:My colleague Allison Young and I, we were like, okay, like this is a pretty good low tide. Like, let's just go see what we can see. And we went out to Pillar Point and there were no starfish. It was just like the most bizarre feeling. I was still at this place that was like spectacularly beautiful, covered with algae, covered with seaweeds. All these other invertebrates are there. But like, there's just something kind of off about it. It's like going to a familiar place and something being wrong. You know, it's like going into your room if somebody had like moved your stuff like all slightly, right?

13:25Rebecca Johnson:And you're like, what's wrong with this room, right? So it has that like disconcerting, like unsettling feeling. And for us, I mean, at that moment, when we saw all these stars that had disappeared. Like, we didn't know what was going to happen. And they, like, play this huge role in maintaining these ecosystems. And so to have them just gone, it was this moment of, like, really deep uncertainty.

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14:11Peter Roopnarine:at insanely cold temperatures, how will they ever become useful to most people?

14:16Rebecca Johnson:My name is Olivia Lanes. I am the Global Lead for Content and Education at IBM Quantum. I want to emphasize that actually cooling down a quantum computer is not really as hard as I think people think it is. It really is just the push of a button that can take your entire infrastructure down to 10 millikalvin. That is not the challenge, scientifically speaking. I also want to emphasize that in the future, we don't envision everyone having their own quantum laptop. Quantum computers are going to live in a data center. Data centers already have their own cooling infrastructure. It's not going to be something that you have to learn how to install and work on a personal level, But that doesn't mean that the discoveries made with the technology won't affect every person.

15:06Rebecca Johnson:Quantum computing has the potential to touch almost every industry that you can probably think of. If you would like to learn more, you can do so at ibm.com slash quantum.

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15:26Rebecca Johnson:My boss asked for results, so I opened my dashboard for the only positive-sounding metric I had. Impressions.

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16:04Rebecca Johnson:Hear the story in every heartbeat with Apple Watch Series 12. The features described are for wellness purposes only and not for medical use. iPhone 11 or later required. Based on Apple-conducted study of heart rate accuracy, August 2026. Visit apple.com slash apple watch series 12.

16:21Rebecca Johnson:Flavors are there. It's very clean. It's very, um, thalassic. Thalassic? oceanics.

16:28Peter Roopnarine:When Rebecca looked out at her familiar tide pools and saw that the sea stars were mostly missing, she was worried because she thought a big change like this might throw that tide pool ecosystem she loved out of balance. And that was, it turns out, a pretty reasonable concern, because it is exactly what happened to another ecosystem, one that is not very far away distance-wise from some California tide pools, but can seem like kind of a different planet almost. To get there, you have to move a little ways beyond the rocky intertidal into water that's maybe 50 to 100 feet deep. And that's where you can find the California kelp forests.

17:17Peter Roopnarine:Imagine, if you would, golden brown kelp. It can be massive, sometimes 100 feet tall. And these are called kelp forests for a reason. Ideally, they're sort of lots of kelp growing together, like trees almost, with sunlight kind of filtering through them in green and gold. Also like a forest, these places are full of a huge diversity of animals. So in this case, everything from sea lions to octopus to abalone. Now, on land, in a forest, right, you have gracers, herbivores like deer, and you have predators like wolves that eat those deer. So a herd of hungry deer can decimate trees and undergrowth by eating everything.

18:01Peter Roopnarine:But some wolves can keep them in check, right, and keep the ecosystem healthy and balanced. The same is true for the California kelp forests. They have grazers, animals like the purple sea urchin, which is a spiky purple pincushion that eats a lot of kelp. And then they have a very important wolf that keeps the pincushions in check, which is the species of sea star known as the sunflower sea star.

18:27Rebecca Johnson:Sunflower stars are amazing. I mean, they're gigantic. Imagine, it's like as big as like a car hubcap, maybe. The ones I saw as a kid were so big you had to hold them with two hands. They have tons of arms, like in the 20s, 22, 24. Some people think that they can count them and there's consistency, but I'm actually not sure. They're really beautifully colored. They have a lot of variation, but they're generally purpley with some pinks, sometimes a little more orange. And they are voracious predators. They eat tons of stuff. And they're pretty indiscriminate. They eat lots of different things. including grazers like urchins.

19:09Peter Roopnarine:But because they're sea stars, they also fell victim to that sea star wasting sickness that I told you about. In fact, they were one of the hardest hit species.

19:20Rebecca Johnson:This lack of the sunflower star in the kelp forest, especially in Northern California, along with the warming waters, because remember we have warming waters, right, led to the increase of urchins. And the urchins then ate all the kelp. And the warming water didn't help kelp because kelp don't really want warmer water. So in many places you have these urchin barrens where it's like mostly urchins. We lost a lot of kelp forests along the Northern California coast.

19:51Peter Roopnarine:The transformation from dense, diverse kelp forests to urchin barrens is just one example of what can happen when things get out of balance in an ecosystem. So again, it makes sense that Rebecca was worried when she noticed that the stars were missing from her tide pools all those years ago. She didn't know exactly what could happen, but she was afraid that such a big change could have real consequences for the tide pools. Ultimately, though, while some species like the sunflower sea stars have not bounced back in California, other species like bat stars and leather stars and ochre stars, they have made a comeback.

20:34Peter Roopnarine:And the tide pools have not met the same fate as so many of the California kelp forests, right? They have not been turned into some equivalent of urchin barons. What worries Rebecca is that as more things change, something else might disrupt the tidepool's balance. She's worried, for example, about the hungry, hungry grazers that have gobbled up the kelp forests. They still need something to eat. And she says that she's been seeing more of them coming into the tidepools.

21:04Rebecca Johnson:They've come into the intertidal and they're eating their, like, you know, not first choice food, but they're eating the kelp, the intertidal kelps. That could affect the ecosystems there.

21:15Peter Roopnarine:And meanwhile, temperatures are still warming over time. So tide pool ecosystems are still changing, which is having its own effects.

21:24Rebecca Johnson:Things are shifting their ranges, like ranges are moving north. We don't actually know what happens when they move north. We don't know exactly what those changes will lead to for nudibranchs, for sea anemones, for sponges, for other encrusting things. Like, we just don't know all the, like, downstream effects of that.

21:45Peter Roopnarine:Part of Rebecca's job is predicting what comes next for these ecosystems. But that's hard, right? It's hard because it's hard to nail down cause and effect in the ocean. It's hard to tease out exactly what the effects of the marine heat wave were or what the effects of ocean acidification are or sea star wasting or changes in predators or any number of different factors that can potentially shake up an ecosystem. But also, it's hard to make sense of how big a deal any given change might be, right? These ecosystems have bounced back from some pretty big blows in the past. Like, fur traders wiped out Stellar's sea cows, which is a species that helped shape the kelp forests.

22:30Peter Roopnarine:And then sea otters, an important predator, they were also hunted close to extinction. Things like sea star wasting and heat waves have also happened before. So sometimes stuff, big or small, just changes, you know? And how do you know what changes might be okay, ultimately?

22:52Rebecca Johnson:That's a good question. And I've spent a lot of my career studying exactly that. And literally what I study is the question of why do ecosystems persist as long as they do?

23:07Peter Roopnarine:I met up with Peter Ruppnerein in his office, full of bookshelves and fossilized shells. He is a paleontologist at the Cal Academy of Sciences who studies how ancient ecosystems were affected by things like dramatic climate change. And he's trying to figure out how that might relate to ecosystems today.

23:26Rebecca Johnson:If you look in the fossil record, one of the things that's really remarkable is that ecosystems can last a very long time, millions of years. Species will come and go in those ecosystems, but what makes the ecosystem, so the types of species, what they do, who they do it to, and so on, that doesn't change. That can last for millions of years.

23:49Peter Roopnarine:It's kind of like a baseball team. The team's always going to need pitchers and shortstops and outfielders. But a specific pitcher can retire.

24:00Rebecca Johnson:The sea otter is leaving Northern California because it's been hunted almost to extinction.

24:06Peter Roopnarine:The team might hire another pitcher or just have one of their other star pitchers step up.

24:11Rebecca Johnson:The Sunflower Sea Star will be taking over more of the pitching. Look out for its famous five-armed curveball.

24:16Peter Roopnarine:But Peter's research also looks at the moments when ecosystem teams fall apart.

24:22Rebecca Johnson:They do eventually come to an end. And that's the ballgame. They tend to come to an end during major events in Earth's dynamic. So things like volcanism, you know, the size of Siberia, an asteroid hitting the planet, you know, really extreme, extreme changes.

24:48Peter Roopnarine:Too many changes and you just can't play baseball anymore. So Peter can't know exactly what the future holds for California's tide pools or its kelp forests or any marine ecosystem. But he is worried.

25:04Rebecca Johnson:You know, the thing that many of us lose sleep over is that, yes, these things that we love, we treasure, we could be staring down the barrel of changes that we're not really imagining yet. And as you pointed out, I mean, the world is different. My world, I grew up, I'm from the Caribbean, and I grew up there loving the ocean. I still remember my first time on a reef. I was really little, and it blew my mind, and I think it changed me forever. So I share that experience with you. but my parents, you know, my mom was from Jamaica, my dad was from Trinidad, they described things that I never saw.

25:49Rebecca Johnson:And so that's interesting. That's always been a little bit disturbing, but there's still beauty out there. And now these days, I just wonder, well, you know, we can still find beauty in a kelp forest that has too many urchins and no sea cows. We still find them beautiful. We get that sense from them. How long is that going to persist? I think that's a question that everybody should be asking themselves very seriously, because I've only very recently come to the answer that yes, I do think we're looking at potential endpoint for some of these systems.

26:38Peter Roopnarine:And yet, he keeps doing his research, hoping that it will be helpful. And so does Rebecca.

26:45Rebecca Johnson:I wouldn't be out here if I didn't have hope that, like, what we're doing can make a difference.

26:52Peter Roopnarine:There are lots of people who are still trying to do something. There is a collaborative, large-scale program to try and rear sunflower sea stars in captivity. and potentially reintroduce them to the ecosystem and restore a baseball star. The California state government has partnered with nonprofits and commercial fishermen to try and clear urchins and restore kelp. There are researchers studying the genomes of sea stars that did recover from sea star wasting to see what could be learned about what made them resilient. And Rebecca has projects with a community science app called iNaturalist.

27:28Rebecca Johnson:I don't know if you know about iNaturalist.

27:29Peter Roopnarine:It basically lets people ID plants and animals, so anyone who goes to the tide pools can upload all the life forms they see.

27:37Rebecca Johnson:And those photos, with locations and timestamps, they can help Rebecca and her team figure out how populations are changing,

27:46Peter Roopnarine:or model the future of this ecosystem, and even potentially serve as a warning system if there are big die-offs again, so scientists can try and intervene earlier. As one researcher told me, no one person can protect marine ecosystems alone. But she at least takes heart in all the different people contributing to the effort. And Rebecca, for her part, wants to get as many people excited about the tide pools as she can.

28:16Rebecca Johnson:You're like, OK, well, here I am. How can I enjoy this place, teach other people about this place, bring people to this place so they love it and they can bear witness to that change.

28:28Peter Roopnarine:She brought me to her favorite place, Filler Point, to show me the nudibranch pool and the brittle stars and a clam that squirted a massive stream of water right at me. Just treasure after treasure.

28:42Rebecca Johnson:It's not a rock, but look. Wait, it's not a rock? It's a sponge. It's a sponge. Here, feel it.

28:48Peter Roopnarine:It looks like a rock. And when we spotted other tide pools, Rebecca brought over some nudibranchs to show them, too.

28:56Rebecca Johnson:I couldn't resist picking them up, so she. They're amazing. So this is them out of water. They're sea slugs. Spectacular. That's gorgeous.

29:05Peter Roopnarine:Walking around with Rebecca, I felt the way I felt as a kid. I'm just happy to be alive and outside.

29:13Rebecca Johnson:There's also a great blue heron hunting. Do you see it? It looks like straight ahead. Yeah, yeah, yeah.

29:19Peter Roopnarine:It made me realize that right now, there are still brightly colored sea slugs off the coast of California. Also, we got some snails. There are still crabs and clams and urchins and sea stars. And we can still hold them in our hands. Oh, like there's these tiny, tiny shells, like iridescent shells. And we've been just like walking across that. Yeah, we're just walking right over it. We can still explore the tide pools and share them with each other. In the midst of climate change and a future that is going to be hotter and harder and more difficult for people,

30:02Rebecca Johnson:you have to have joy. You have to just still have this quest to understand how things work and how things are changing. And also being like, hey, what are the things we can do? What are the things that we have control over? Like, I struggle with it. I feel like marine systems especially are, like, pretty complicated to think about restoring, to think about, like, what do you actually do out here? How do you protect things? But that's just, like, you can't stop doing that because then you've kind of lost everything.

31:01Peter Roopnarine:Okay, I promised my editor that I would sit and think about the tide pools for a few minutes, so I'm going to sit and think.

31:26Okay.

31:32Peter Roopnarine:It's closer to 8.30. The sun has come up completely, but, like, the weather is kind of gray. And I'm just sitting on, like, a rock that's sort of covered in iridescent algae, which is literally its name. but also it is quite iridescent.

32:02Peter Roopnarine:So when I, okay, the camp I would go to every year, the camp that actually brought me out here,

32:12was kind of granola.

32:13Peter Roopnarine:Like we would sing, we would sing a lot of songs around the campfire, like old classics. And there's a song that I feel like keeps coming to mind as they work on this story, which is, it's a song about, like, loving crawdads, and, like, you go fishing for crawdads, and everyone loves crawdads, and then at the end of the song, it just makes a sudden shift, where they're suddenly singing about, like,

32:43Peter Roopnarine:what are you going to do when the lake goes dry? And the song repeats. It goes, what are you going going to do when the lake goes dry what are you gonna do when the lake goes dry what are you gonna do when the lake goes dry sit on the bank and watch the crawdads die what are you gonna do when the crawdads die what are you gonna do when the crawdads die what are you gonna do when the crawdads die sit on the bank until I cry

33:12Peter Roopnarine:I don't know as a kid I was always like what the heck or these verses. This is such a fun song, and now it's so sad.

33:27Peter Roopnarine:And now I'm just really glad those verses are in there, because, yeah, I don't know. This is such a fun song, but it's also a little sad.

33:42Peter Roopnarine:Anyway, I found a hermit crab.

33:48Peter Roopnarine:Rebecca, look at this hermit crab. Look at this shell. Oh my gosh, this shell is amazing.

33:56Rebecca Johnson:What kind of shell is that? I think it's an epitoneum it's called. It's all covered with coral and algae, so it would be like... Oh, that's why it's like... It's just a fish. Oh, Lord, Lord, what you gonna do when the lake goes dry? Set on the bank, what you call that die? Honey, man, what die? Tell my cross that's three-foot die, honey. Lord, Lord, tell my cross that's three-foot die. Hey, Lord, Lord, tell my cross that's three-foot die. I'm with them all, but they ain't none of mine. Honey, pay for my What you gonna do when the lake go dry? Honey, no, no What you gonna do when the lake go dry?

34:50Baby, no, no

34:52Rebecca Johnson:What you gonna do when the lake go dry? I'll fill out the bank, what you gonna do? Honey, pay for my Oh, no, no

35:11Peter Roopnarine:If you want to contribute to Rebecca's iNaturalist project, please look up Snapshot Cal Coast. We will link to that in the description as well. Meanwhile, this episode was produced by me, Bird Pinkerton. It was edited by Jorge Just with help from Meredith Hodnott, Matt Collette, and Paige Vega. Noam Hasenfeld made the music. Christian Ayala did the mixing and the sound design. Kim Slaughterback checked our facts. Julia Longoria is the fact that some frogs have little spade-like feet that help them burrow. And I am always, always, always, always grateful to Brian Resnick for co-creating the show.

35:56Peter Roopnarine:Thanks also to Drew Harvell, Ashley Kidd, Lauren Schiebelhut, Kylie Love, Nat Lowe, and Chloe Davis for taking the time to speak with me for this story. Thanks to Megan Ely for all her help in organizing things. And thank you forever to the late, great Michael Rossman and to Lee Temkin. You changed my life. The 1939 recording of the Crawdad song that you heard was from the American Folklife Center. If you have an ecosystem that you love, someplace in the world that makes you happy to be alive, please tell us about it. Tell us why you love it. Tell us if it's changing. Write in. Send us a recording of it if you can.

36:41Peter Roopnarine:We are at unexplainable at Vox.com. If you want to support the show and help us keep making it, please join our membership program. That is at Vox.com slash members. You can get ad-free podcasts, among other perks. And you also get unlimited access to Vox journalism. Also, if you sign up because you love Unexplainable, please tell our bosses. They love that for us. You can also support us by leaving us a nice review, perhaps, on your podcast platform of choice. Or a rating. Or just by telling people in your life to listen. Unexplainable is part of the Vox Media Podcast Network. And we're off next week for the holiday, but we'll be back in your feed on July 14th.

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