SPEAKER_00: I gotta say the first experience I had with a great white, or I should say the lead up to the first experience was filled with terror.
SPEAKER_01: That's National Geographic explorer Gibbs Kaguru. Gibbs is a Kenyan scientist who studies sharks and he's talking about the first time he dove with great whites. He's on the coast in South Africa.
SPEAKER_00: I was certain I was going to die. I was like, yeah, I'm in this situation, the sea looks a bit choppy, it's grey skies, which is by the way perfect sharky conditions, and I'm about to get in a cage. I'm basically like a gummy bear for this two tonne animal. And I put the wetsuit on and I remember just staring over the edge of the boat into the cage and thinking, you know, this is what my coffin's going to look like. And as soon as you see your first great white, your, I shouldn't say your, my imagination about them being these bloodthirsty man-eaters immediately dissipated. Because you saw a curious, beautiful, fierce, graceful animal just, you know, enjoying its surroundings. There was no malice or inspired cruelty to its actions. And you could see that. And I always tell people that, or they're like, man, it must be scary going out to work every day. And I'm like, no way. Like once you see what I've seen, you'll never have that, you know, weird notion that these sharks are anything less but just beautiful animals in the wild.
SPEAKER_01: I'm Peter Gwynn, Editor at Large at National Geographic, and you're listening to Overheard, a show where we eavesdrop on the wild conversations we have here at Nat Geo and follow them to the edges of our big, weird, beautiful world. This week, we meet a guy who went off to swim with sharks because, well, he didn't know what he was going to do with his life. And in the process, he fell in love with these misunderstood wild creatures. He'll tell us why they drew him in, what it's like to free dive with sharks, and what genetics can tell us about these ancient ocean animals. More after the break. Fuel your curiosity with a free one month trial subscription to Nat Geo Digital. You'll have unlimited access on any device, anywhere, ad free with our app that lets you download stories to read offline. Explore every page ever published with a century of digital archives at your fingertips. Check it all out for free at natgeo.com slash explore more.
SPEAKER_00: Can you sort of paint that scene of the first time you actually put on scuba gear and went
SPEAKER_01: and dived with sharks? I was doing this pre-med program and I didn't love it, to be honest.
SPEAKER_00: My study advisor at the time was like, I know you don't love it. And he knew I was not really going to go anywhere with it. So he sends me this bulletin to come dive with sharks in South Africa.
SPEAKER_01: This thing that your professor saw, what was it exactly? Was it like a research project or was it like a tour company? What was it?
SPEAKER_00: Yeah, it was a tour company that took clients out every day to see great whites. You stick them in the cage, they see a whole bunch of great whites and they leave having their lives absolutely changed. And I thought that was a crazy idea. Sharks to me appeared to be one of the most dangerous things on the planet. But at that stage in my life, I was sort of confronted with two types of fear. The first was continuing on with this program that I was discontented with deeply for the rest of my life. And the second one was get eaten alive potentially by a great white, which is the fear of death. But long story short, I chose the sharks. I chose to don the wetsuit and get in the water. Because for me, the fear of losing a life well lived was far scarier than losing life itself. And being in the water with sharks gave me a whole world of new possibilities that I could thrive in and love. I also found love for sharks. I can't describe it any other way because I remember the first moment I got a chance to step away from doing shark work, I felt like my world was crumbling. And I don't see it going any other way. I want to do this for as long as I'm physically capable.
SPEAKER_01: Well, okay, so that's super dramatic. So go from preparing to take the medical entrance exams versus going to dive with sharks. So what happens? You get on a plane and how do you even begin this process, diving with sharks?
SPEAKER_00: The first thing was improve my competency in the water, which meant learning how to dive, learning how to boat, and then also being comfortable in a variety of situations with wild animals. And that's something that I feel like is definitely a skill. But there's also an intuition about figuring out how an animal thinks works. And it also plays into how safe you can be around them. And this all just comes with time and experience. And six years working at a shark diving company was the crash course that I needed to get me to the level where I can be a confident shark scientist. And I was an intern there for six months. And after that six months, like I said, I had an opportunity to walk back and go and take my medical school entry exam. And I was like, hell no, I'm not going to do that. Put me in the water again, man. I couldn't imagine not doing that. It's one of those things where I don't really remember what life was like before I saw my first great white. It was just seeing great whites and then I'm like, yep, that's it.
SPEAKER_01: So how did you get from that into the research part, into the sort of the academic world of sharks?
SPEAKER_00: Yeah, I felt uninspired with my pre-med program. And for the first time in my life, I had wonder again. And that's what pushed me to be like, okay, I have these sharks and I have maybe some academic curiosity. Can I marry these two things together and learn as much as I can about these animals?
SPEAKER_01: So what was it like the first time that you weren't inside a cage when you went down to study sharks? What did that feel like? I mean, I know you said that you got this sense of like, you sense they're not the creatures that we've imagined them to be through your experience with the tour company. But then when you actually get outside the safety of the cage, what does that feel like?
SPEAKER_00: Being in the water with sharks is, it's an out of body experience. You feel like you're being watched and you're sort of watching yourself being watched by these animals. And it's freeing at the same time because it feels like you're suspended in air and there's these things just floating around you, just observing you. And most of the time, they don't even stick around because you're really not that interesting to them as far as like a food source goes. So they come out, they check you out, they're like, oh, what is this really weird lanky thing floating in my environment? They check you out for a little bit and then they dart off. And those are the moments that make me sad actually because I'm like, man, I want to see this thing as much as possible. How do I get it around me? And this is why I continue doing what I do is because that moment when the shark swims away from me is like, man, okay, I need to come back tomorrow and do this again so I can spend that much more time with it just to see what it does.
SPEAKER_01: Sharks are such a topic of conversation in the United States. And we can talk a little bit about the Jaws effect. But Jaws came out and really colored a lot of people's view of sharks in the United States. Well, what do people in Kenya, like growing up, what was the attitude? Was there a similar sort of like perception of them?
SPEAKER_00: I think that you're touching on something important there with the Jaws effect. And I think the impact of that film permeated just about every corner of society because even growing up in Nairobi, which is nowhere near the ocean, I was under the impression that sharks are dangerous. And I had this notion growing up for my entire childhood, even when we went to the beach for the holidays, it was always like, don't go out too far because they're going to get you.
SPEAKER_01: Yeah, right. So that's become a universal phenomenon, I guess, the monster in the ocean that's lurking out there.
SPEAKER_00: I think people need to hear more inspiring shark stories. Unfortunately, we had one movie that changed the scope of sharks PR for generations. I think people were sort of inclined to having a fear about things they don't understand. But when that fear was given a face and a name, Jaws, that immediately solidified that in our psyche as the thing we have to avoid at all costs. And if we can't avoid it, then we have to kill it. And that's just what people do. When we feel vulnerable, we want to make sure that there's no way in the future where we'll ever feel threatened again. And this spells the end not just for sharks, but for a healthy working environment, which is what we need too.
SPEAKER_01: Can you kind of, for the person listening that doesn't know a lot about this, can you kind of walk us through the evolutionary history of sharks? Yeah, so based on what we know from their genetic history, we see that they predate
SPEAKER_00: trees. And that means they've been around for eras. Oh my gosh, are you serious?
SPEAKER_01: I had no idea. Older than trees?
SPEAKER_00: Yeah. Wow. What that tells me is that these animals are so perfectly designed. They've been around through eras of mass extinctions. And that is so remarkable, especially when we look at what's happening today, when their populations are being forced to adapt to humans and bounce back from the brink of extinction. And like I said, humans are the primary cause that's making these animals that have been around for millennia be at risk of extinction.
SPEAKER_01: Well tell me a little bit about the impact that humans are having on sharks. I mean, I take it it's more than one, it's multifaceted. Is there any one particular area of this crisis that you've looked at?
SPEAKER_00: The work that I'm doing in the Maldives is really based on learning about the direct human impacts on shark populations. Over about a 40 or 50 year period, people had fished the Maldives out nearly to a population collapse. And then the sharks bounced back. We thought that it was going to be all fine, but now these sharks are coming back with a skin disease, essentially. And it looks kind of like spots that you'd get from like a sunspot almost, where you just lose the ability to create pigment. Sharks have melanin pigment just like we do, which is actually kind of cool. But they lose this ability and this gene that codes for melanin pigment is linked to so many other functions in the shark's body, as well as ours, that it's potentially giving them other deformations as far as their development goes.
SPEAKER_01: So what's the answer to that? Is there some, have you guys isolated a specific cause for that that can be addressed?
SPEAKER_00: Again, this goes back to that whole complexity of nature. If you break it, it's really difficult to put back together the way it was. And over time, we've realized that conservation is so vital, not just from a, let's see how many animals we have, but we need to have a diverse array of animals. I know the term diversity gets thrown around a lot. And it's in the context of diverse people, diverse ideas. But when we're talking about genetic diversity, we're really talking about the strength that binds populations together. And without diversity, you eventually breed in weakness. And that's what these sharks are sort of dealing with now is we've shrunken their gene pool to a gene puddle. And there's not that many genes that can help their potential of survival. And then you come out with sharks that have spots that aren't able to protect themselves from harmful UV rays and a litany of other problems.
SPEAKER_01: One of the things I'd heard is that you'd studied about how great white sharks can change their color. I'd never heard that before, man. That's crazy. How does that work?
SPEAKER_00: So I first heard about sharks changing color from my employer when I worked at the cage diving company. And I remember thinking that was the craziest thing I've ever heard because we saw the same shark but I didn't see it change color, but he would swear by it. Then I went to visit other cage diving companies and they said the same thing. Again, me being the skeptic, I thought it was some kind of industry joke that I just wasn't in on. And as we kept going, I started realizing that maybe there is something to this. So we just devised an experiment to expose this. We being myself and Ryan Johnson, my mentor. But we essentially found that great whites do have this ability to modulate their color to be better suited in their environment. There are certain situations where they need to be camouflaged to hunt better. Maybe be camouflaged to defend themselves from a larger predator like an orca in their environment and they'll go down to the bottom of the ocean where the colors are a lot more muted and they go pale. So there's this interplay of using their skin to be better predators and also a less viable prey.
SPEAKER_01: And that is crazy. One of the other things I'd heard is that they can really heal themselves. That they have this ability to regenerate quickly after they've been injured or sick.
SPEAKER_00: Yeah, we've seen this happen quite a number of times with our sharks. On any given day, you'll see a great white with this most grievous wound out of its side and you think, oh, there's no way this thing is going to recover from that. Like an entire chunk of its flesh was removed. You watch this shark go around your boat over time and then within a year, it's like it was never hurt. It's like it had never experienced this trauma. And what we've also learned through genetics is that these sharks actually have genes that are geared towards this adaptive immunity that essentially gives them a superpower like Wolverine where they can take anything physically damaging and recover from it. I think that is one of the coolest discoveries about shark adaptations. And it even has biomedical implications because we can potentially isolate genes like that and use things like gene therapy to assist people who need to, I'm just spitballing here, like regrow limbs or recover from cancers. The applications are endless, but we just need to do more research to find out how we can actually use this ancient animal to fix us, which is cool.
SPEAKER_01: What's the thing that surprised you the most during your time working with sharks? Is there been anything that just like blew your mind? Like, wait, I mean, you've already kind of listed a few that have blown my mind, but is there any like shark behavior or a specific encounter where you were like, wow, I totally didn't expect that? Yeah, I will say the thing that surprised me the most about sharks was learning about
SPEAKER_00: shark social networks. And this was during a very difficult trial I had when I was working in the Maldives. And I was trying to get tissue samples for my PhD study, which I'm currently doing. So I went and found the juiciest, freshest, bloodiest tuna that I could find, which anything by sea or land would go crazy for. It's good eating. So I set this tuna on a hook and laid it out in an area where I know these blacktip reef sharks would occur. And for two months, I watched every day one of these sharks observe my bait and turn away. This was the most delicious meal that I could have prepared for them because it's a nice oily fish. It's highly nutritious. And like I said, any animal at sea or land would go crazy for it. And yeah, like any chef who's prepared a delicious meal, I became very despondent. You know, I asked myself, why are these sharks not taking the bait? And as it turns out, these sharks are a lot smarter than they look. And it was for sure not very difficult for them to outsmart me, which I took, by the way, very personally. And the reason for this, the surprising thing, is that these sharks actually have a cohesive social network that allows them to identify threats in their environment and then collectively avoid them. And interestingly, these sharks have seen fishing gear before. They're a historically overfished population. So they see me, a scientist, coming in with the same fishing gear that a fisherman has used and they know that is danger. And there's actually a really interesting paper about this written by Johann Murier, based out in French Polynesia. We know that these sharks are doing this. The crazy thing is we just don't know how. How do they communicate? In any case, through that trial, I licked my wounds. I called my buddy Walker, who by the way is a world-class waterman. We got a whole bunch of equipment, devised a plan, and then we successfully managed to catch these sharks. Through that, my ego took a really big hit. Because I'd been working with great whites, you know, and these little black tips had managed to play me for a fool. It taught me a lot of new crucial skills, but one very important lesson I learned is that I actually don't know s***.
SPEAKER_01: The more you learn, the more you realize you have to learn, right? Yeah.
SPEAKER_00: I saw what was happening to my sharks. These animals, which I loved so dearly, were taking such a hit from people. It made me feel a little bit helpless because the love that I had for them was not backed by action. That's when I realized I got to start talking about this. I got to tell people what's going on, what I'm seeing in the environment, how the habitat of these sharks is completely destroyed, how they have no more food sources, and the fact that in the midst of all this, people are still going out and collecting jaws as trophies. I don't know how this is all going to change, but I know that it's incumbent upon me who has seen these things to be the canary in the coal mine and say, hey, this is happening. Are you aware?
SPEAKER_01: If you like what you hear and you want to support more content like this, please rate and review us in your podcast app. And consider a National Geographic subscription. That's the best way to support Overheard. Go to natgeo.com slash explore more to subscribe. And hey, for more on Gibbs' journey and his research, check out our story about him online. We've also got an article about how great whites changed their color to sneak up on prey. Plus, you can watch Gibbs in a National Geographic documentary, Camo Sharks. He and other scientists try to catch sharks in the middle of their color changes. And if you just can't get enough sharks, we've got a whole bunch of Sharkfest stories for you, including how drones are changing how we observe and think about sharks. That's all in your show notes right there in your podcast app. This week's Overheard episode is produced by Alana Strauss. Our other producer is Kyree Douglas. Our senior producers are Brian Gutierrez and Jacob Pinter. Our senior editor is Eli Chen. Our manager of audio is Carla Wills. Our executive producer of audio is Devar Ardilon. Our photo editor is Julie Howe. Ted Woods sound designed this episode and Hans Dale Su composed our theme music. This podcast is a production of National Geographic Partners. The National Geographic Society, committed to illuminating and protecting the wonder of our world, funds the work of National Geographic explorer Gibbs Kaguru. Michael Tribble is the vice president of integrated storytelling. Nathan Lump is National Geographic's editor-in-chief. And I'm your host, Peter Gwen. Thanks for listening and see y'all next time.
