The Slow Regrowth of Vulnerable Coral Reefs is Solvable

due to climate change. When you consider that nearly twenty five percent of all fish spend at least part of their lifetime in the reefs, and that the reefs support coastal tourism in various ways, you can start to understand the scale of this loss. And there's more. Hurricane Irma, which was in twenty seventeen, had twenty five foot waves

heating the Florida reef track. We had a storm surge at our building of only five foot, So if we didn't have a reef system there, or a healthy reef system there, you can imagine that that storm surge in those waves would really decimate the land. Sarah Hamlin is a biologist at the Moat Marine Laboratory. She's devoted to coral reef restoration. She helps to maintain twenty one species of stony and branching coral and splits her time between the loo Key Reef and her land base on Summerland

Key in South Florida. It's amazing. You're like an underwater gardener. That's exactly what we are. We are underwater gardeners. Her lab uses a process called micro fragmentation and fusion, and it's impact on underwater wildlife is anything but tiny. My name's Sarah Hamlin. I'm a scientist at Marine Lab in Florida, and my solvable is regrowing coral reefs forty to fifty times a speed that coral grows in the wild. There's a number of reasons why coral reef is really important.

I mean, who doesn't love going out snorkeling and seeing colorful reefs teeming with beautiful fish. But they also provide us with goods and services, whether that be tourism or employment. The food on our table, and for Florida alone, our reef system here is estimated to be worth about eight billion dollars. Not only that, but these reefs protect our

land and our property from things like storm surge. So a really good example of this is Hurricane Irma, which was in twenty seventeen had twenty five foot waves hitting the Florida reef track down in loo Key where I am, and we had a storm surge at our building, which is in summer and key of only five foot. So if we didn't have a reef system there, or a healthy reef system there, you can imagine that that storm surge in those waves would really decimate the land. Yeah,

so I can hear your Australian accent. Australia of course samous for the Great Barrier reef. What's going on with climate change and coral reefs around the world worldwide, We're seeing a reduction in live coral cover. So this is across the world, whether it be Australia, the United States,

or any of our Pacific or Caribbean island nations. You might have heard of coral reefs as the rainforests of the sea, and that's saying is because even though coral reefs take up less than one percent of the sea floor, around twenty five percent of all known marine species actually rely on coral reefs at some stage of their life.

We're seeing warmer oceanic temperatures, We're seeing a lot more pollution going into the oceans, and this is resulting in loss of live coral tissue almost as much as any consequence of climate change. I can think of the people who are really in contact with this are shocked and appalled and upset at a level that those of us who don't come into coral into contact with coral on a daily basis, I think, don't really get. I mean,

I you're in the Florida Keys. I have a nephew whose into skin diving and spearfishing in Miami, and he's a young guy, and just in the years he's been doing this the coral around Miami, I mean, he's like shocked and upset when he sees it and says he can't really fish anymore, just because of the change in the last decade. We have lost around ninety percent of our coral cover in the last forty or fifty years.

And some of the reefs in the Keys now or the Florida reef tract or as low as between four and six percent stony coral cover, which is quite low. So we're talking on zoom and you have a fantastic backdrop of coral. And I don't know enough of our coral to know what kind it is. But we hear these terms like staghorn coral and I heard of elkhorn coral. What are the main forms of coral that you're working with and what do they look like. We have branching

corals and we have massive corals. So branching corals are the staghorns and the elkhorns, and you if you can picture what the antlers of a staghorn or elk horn look like, they look exactly like that. So skinnier branches really perfect three dimensional habitat for fish and shrimp and all the little reef critters out there. And then we've got our massive corals, and these might be brain corals, which essentially look like the folds and grooves of a brain.

Star corals which have their polyps, are like little cups or little stars. And there are reef building corals. They're the corals that are recreating the reefs and really growing that larger reef structure that remains stable after storms. Your lab, as I understand it, is working to restore coral that's dying through a process that's called micro fragmentation and fusion. And that sounds cool, So could you please explain that? Yeah, so it my marine labs. Essentially, what we do is

we we call this micro fragmentation and reef skinning. So we take a larger parent colony of coral and we cut it into very small pieces. We're talking one poll up or around one centimeter squared. And this process where we cut the coral, we abraid the tissue and remove excess skeleton, really promotes incredibly accelerated tissue growth in these new fragments. So we liken to this is like when you cut your skin, your body works over time to

really rapidly heal that cut that you've created. So when we raise these tiny micro fragments, we raise them by the thousands and raise them with their genetic clones, which are corals that have exactly the same DNA so they came from the same parent colony, and they will be raised on land at MO Marine Lab here for up to a year, and then after that they've basically filled out their substrate, which is what we call a plug,

and they're about seven square centimeters. We then take those individual corals out onto the reef into the Lower Florida Keys and we plant or attach them in really tight clusters with their genetic clones so it kind of looks like a pepperoni pizza. It's about that size, and you imagine the peronis are the little corals there, and those corals still continue to grow really rapidly onto the reef. They recognize their clones and they fuse together to form

one large colony, and that's what we call reskinning. So because coral becomes sexually mature based on size and not how old they are, by strategically outplanning these with their clones and having them glow really rapidly, we're able to grow corals to reproductive size in only a few short years. And that's compared to them typically taking decades for wild colonies. So you're kind of blowing my mind here. I mean, I didn't even know that coral reproduced sexually. I thought

it just grew. Well, it doesn't only reproduce sexually. The process of micro fragmentation is actually an asexual reproduction. So by cutting smaller pieces and having it grow, there's nothing sexual about that. Some corals out on the reef naturally

produce both sexually and asexually. So staghorn coral, for example, when storms come through, it breaks into smaller pieces, which gets scattered around the reef and get lodged into different places, and they'll continue to grow out as an absolute genetic clone of the piece of coral that they broke from. I thought the reason this was such a problem or what the main reason is that it grows so slowly

and it's being destroyed so quickly. So does this method, this microfragmentation method, it help you grow it more at the speed we're losing it, that is? And what are the comparative speeds? I mean how fast they're dying off and how fast can it be replaced through this method? So the process of microfragmentation, we estimate that we're able to regrow coral reefs forty to fifty times faster than the speed coral grows in the wild. And how long

is that? So let's say we microfragment coral, we hold it in our land based facility for twelve months, we put it on the reef. It takes one to two years to fuse together and be sexually chure, so we're looking at three years. A wild larvae that settles on the reef takes forty to fifty or even longer to get to a sexually mature size. Wow. So I have

a lot of questions about this. First of all, when you see the coral in this way through micro fragmentation, is the coral that grows more resilient to climate change or is it just the same coral and will be

afflicted in the same way by what's going on. If we were to just be refragmenting and fragmenting the same coral over and over again, would essentially be putting a monoculture of coral out there, coral that is potentially susceptible to the next disease it comes through or future climate conditions. So that's a really good question. And one thing that MOTE prides itself on is the fact that we are

able to settle and spawn larvae of our own. So we're able to collect gammets from wild coral and coral all grown in the lab, which increases our genetic diversity, so we can make some thoughtful crosses between those coral, and the more genotypes you have, the more inherent resilience you have in a population. Will this work anywhere in the world or is this method specific to the kind of coral you've got down there in Florida. We hold about twenty one species, and we've tried this on a

dozen species and it does work. So we've proved that it's work. It works here. Now people in the Caribbean are also starting to microfragment and grow coral out and it's working for them as well in other countries. So in Pacific nations, I believe the process of microfragmentation and restoration is known. But if we consider the Great Barrier reef, for example, the reef itself is in a little bit

better condition. They're still so they're working a lot with larval dispersal, so they will collect larvae and recede the reef. They're not at the point that the Florida reef tract is at the moment with the gradation. But there's nothing to say that this process isn't going to work with all the other species of coral in the world. With these different approaches to coral restoration, is there competition among them and you have the faith to kind of be

the leading approach to coral restoration? No, I mean absolutely not. So there's a lot of coral restoration practitioners out there, and we have really good relationships with them. All we offer our facility at marine Lab is open for collaboration, so we invite other scientists to come in and do research on our corals. We use our boats to take people out and out plant who are researching corals in

non COVID times. Of course, we head to conferences and presentations delivered by scientists from around the world and really share our knowledge. This problem is too big to make it a business. We really need to be working together, and it's awesome to see so many practitioners from all over the world being in contact with each other to further the science behind restoration. Tell me about the first time you planted coral. The first time I planted coral,

it was great. I felt really accomplished, like what I'm doing is actually making a difference. But the coolest part about that was not actually planting that coral, but it was going back a year later and seeing just how much that coral had grown double its size. It actually sent branches up, so it started to create that beautiful

three D structure. Another cool experience I've had really recently, which is I think something I'm going to remember for the rest of my life, was going out and watching some restored coral of as actually spawn and this is an endangered species that we outplanted. It fused together and it started spawning, and I'm not going to lie, I

had tears in my mask. It was the most heartwarming, wonderful experience that I hope everyone can experience seeing coral spawn and seeing a healthy reef, because for me it was life changing, since few of us probably will ever see coral spawn. What does it look like? What did

you see? So? I was swimming past this coral, not knowing if it was going to spawn or not, and I shone my little red torch on it, and I saw these lumps that I didn't expect to see, which was the gammeat bundles, the eggs and the sperm which looked like little pink circles in the coral poly up

the coral mouth. And then about fifteen minutes later, all at once, the entire colony let those gammeat bundles go and they floated up towards the sea surfers and all the fish came in to have a little bit of a feed as well, and it was just beautiful to see just nature working. It's amazing. You're like an underwater gardener. That's exactly what we are. We are underwater gardeners. Can you give me some sense of what it costs to do this? And assuming this really works, what does it

cost to say of the coral of the world. I mean, you're seeing a process like this, I guess the first question would be to ask you what's it going to cost if we don't save the coral reefs? A lot more, I assume, but I'll back that up now. So we tend to say that coral that we grow on the field, so these are our fast growing staghorn corals. When we take into account staff time, boat time out planting, and

cost of equipment, it's about twenty dollars per coral. And when we look at the coral that we grow in our land facility, it's a little more expensive. The brain, boulder and star corals that are the real reef building corals, and that's around fifty to eighty dollars per coral. So it's not cheap to restore the reefs, but it's very expensive if we lose the reefs. Yeah. Now, water is

continuing to get warmer and warmer year by year. Does this process change if you project the consequences of climate change further decades? Into the future and water temperatures are higher than they are now. Absolutely, so what we do at MOTE is really drive restoration by a solid foundation of science. So we really are looking into corals that are more resilient to future conditions and upscaling production of these corals and using these corals out on the reef.

We end the show by asking if there are things that our listeners can do to help with the problem. What's something that people who are worried about the last and bleaching of coral reefs can do locally? What we do actually has an additive or an amplifying effect on our local reefs. So I'm sure people have heard of the old saying reduce, reuse, recycle, and that actually still

stands through today. So we can reduce our overconsumption, maybe our carbon footprints through shopping locally for produce, maybe growing your own food if you haven't the opportunity to do that. I would also ask people to consider the pollutants that we're putting down the drain or putting onto our lawns,

So thinking about greener alternatives to cleaning products. If you go any these fertilizers use a slow release fertilizer and don't use it in the rainy season, and that's going to go a long way in really keeping all of our watersheds cleaner. If you're eating fish, maybe consider eating fish from more sustainable sources because over fishing and destructive fishing practices are really going to affect the health of

coral reefs. There are actually easy to navigate websites like FishWatch which can help people work out that the fish they're eating does come from a sustainable source and really understanding that we as individuals can make a difference. Sarah Hamlin as a biologist at the Elizabeth Moore International Center for Coral Reef Research and Restoration on Summerland Key. Remember to check out our show notes for links to the suggestions for ways that you can help slow the destruction

of coral reefs around the world. Solvable has brought to you by Pushkin Industries. Our show is produced by Camille Baptista, Senior producer just Slynn Frank. Catherine Girardou is our managing and producer, and our executive producer is Mia Lobell. Special thanks to Heather Fane, Eric Sandler, Carly Migliori and Cadija Holland. I'm Jacob Weisberg. Wow. After talking to you, sire, the only thing I want to do is go Snorre. You definitely should