Rewilding our oceans

We are lucky enough to live, work, and record this podcast on the land of the Ghana people. We acknowledge their ongoing connection to sea country and the importance of Indigenous knowledge in caring for the ocean. Welcome to the OceanPod, a podcast about all things to do with marine science and the ocean. You are once again joined by myself, Dr. Nina Wooden and my co-hosts Professor Brahman Galanders. We are both marine scientists from the University of Adelaide with a huge passion for all things to do with the ocean. Hi, Brahman. Hi, Nina. So in this episode of OceanPod, we have a really special guest, Professor Sean Connell, a leading marine ecologist whose work has transformed our understanding of temperate reef ecosystems. We talked to Sean about his incredible career from diving deep into the resilience of kelp forests to navigating the challenges of climate change, conservation, and science policy intersections. His insights into ecosystem dynamics, his scientific curiosity, and long-term monitoring are both thoughtful and inspiring, and we hope our listeners come away with a deeper appreciation for the temperate reef systems right here in Australia. So Sean's just actually at the International Temperate Reef Symposium, been awarded, I'm not sure what it's called, but one of the top awards that they give out for their researchers, which is amazing. Well, that is amazing. But first, it's time for one of our favourite segments, Tide Talk, where we share something ocean-related that caught our attention this week. Nina, what have you got this week for your Tide Talk? Well, I wanted to talk this week about a conference that I've recently been to, Amzah, Australian Marine Sciences Association, and this year was held in Melbourne. I was really well-hosted, I have to say, very well done to all the conference organizers, they did a really good job at making sure it was like a really accessible and friendly conference, and I feel like everyone was really approachable and so many good talks. I really feel like sometimes it helps to broaden my mind, hearing a lot of what other people are doing in the science, marine science space, and it makes you think about different contexts of how you could maybe bring some of the research you're doing and provide it or apply it in a slightly different way, and it did open my mind a bit to that, so I really enjoyed it. I did present as well. I did a presentation on some of the work we're doing up in the Northern Territory with the Dimiru and Ural Corranger groups, and that was really well received. There was a whole section on marine plastic pollution. There were sessions on lots of different things, though, lots on sea grass, lots on sea country, which is really cool. So I think what I really like about the Australian Marine Science Association conference is it's not just biology, it's you get all aspects of marine science, so oceanography, there can even be some marine chemistry. Exactly, it's really broad. It does open your eyes a bit to all the different stuff that's going on, that's very much like parallel to what we're doing, but we probably should have more crossover and collaboration with some of these different ideas too, so it was really cool. But on the last day, Dr. Scott Bennett from the University of Tasmania spoke, and he also is part of the Great Southern Reef Foundation and shared some insights on, of course, the different threats that we have along our Great Southern Reef, but the algae bloom as well as brought up a lot. He had some preliminary results on some of the algae bloom effects, which was really interesting, and there are heap sickle plenaries, actually. I've really enjoyed the plenaries. I usually sometimes find the specific talks a bit more interesting than the plenaries, because sometimes they're really high level, but this Amsa had did a really good job at getting really diverse plenaries that really fit well together and sort of told this overall story of Harmony, which was a theme of this year's conference, and I just loved it. So I wanted to bring for my tide talk, and Bramam, what about your tide talk? What have you got for us this week? So it's about a cephalopod, and cephalopods, when I see there like either octopus or cuttlefish or squid mentioned in some of the top science magazines, like this one's in science, I kind of usually am intrigued. So my tide talk this week is Octopus's Fall for the Rubber Arm Illusion. I didn't actually know what the Rubber Arm Illusion is, was, but I'll tell you in a minute, and the heading is Octopus's Fall for the Rubber Arm Illusion, just like us. So basically, what it's about is experiments that have shown the Octopus's can feel body ownership, and that's a trait that's usually only found in mammals. So this Rubber Arm kind of trick is if you cover up a person's hand and you place a rubber hand next to it, and then you stroke their hand, suddenly the person will begin to feel the touch of the fake appendage. Oh, it sounds weird to me. That does sound weird. Oh, is that kind of like how if you thought that trick that you people used to play when you're a kid at sleep, over as well you fall asleep, and then put your hand in water, and then that sounds kind of similar. It sounds similar. It's meant to demonstrate how senses work together to create the feeling of ownership over the body. And it's meant to be a fundamental part of self-awareness. So there's this new study that suggesting that Octopus's also do this, and it's the first documentation of the phenomenon outside of mammals. Cool. So is that an experimental based study? I think so. There's a come out of, so it's come out of the University of Rikus. I've probably pronounced that incorrectly. I don't even know where that is. I think it might be in Japan, but I need to have a look. We might need to have a look and then put it in the show notes if we've got that incorrect. Yeah. So it's suggesting that Octopus's perceived this similar level of body ownership to humans and other mammals, and I mean we've already known that cephalopods are complex in terms of cognition and those sorts of things. So, and that they have a complex nervous system. That nervous system evolved independently from vertebrates, and it seems that they also have multi-sensory representation similar to what we have. So yeah. That is really cool. Yeah. I actually heard going full circle here because going back to Amza, I heard a really cool story from Greta Petzel. Yeah. And she was speaking at this ocean. They had this really cool event at Amza where they invited students and young people to come along and learn about why the ocean matters. And she was talking about an encounter she had with an octopus where she half of its body wanting to camouflage to kind of try to attract a mate. And at the same time the other half of its body was trying to defend itself from a different male trying to come in. So that was half one color and half the other. And I think octopus is a crazy. Yeah. Because you can see some really cool camouflage videos on YouTube in places, but it's usually the whole octopus. The whole body was half, half. Yeah. Amazing. Now I'm spreading this story, but anyway I think it was really cool. So that that institution where the work was done is in Japan. Okay. Okay, cool. The health of our oceans is at tipping point. Around the world marine ecosystems from oyster reefs to sea grass beds are being lost at an alarming rate with devastating consequences for biodiversity, water quality and coastal communities. But among the challenges, there are incredible stories of recovery thanks to the tireless work of scientists, community groups and innovators pushing the boundaries of what's possible. One of those leaders is Professor Sean Connell, a world-renowned marine ecologist whose work has laid the foundation for some of the most ambitious and successful coastal restoration projects in the southern hemisphere. From restoring oyster reefs using underwater sound to helping large-scale kelp for forest recovery, Sean has spent decades developing and testing real-world solutions to rebuild the resilience of our oceans. Sean is also a passionate advocate for collaborative and multi-disciplinary solutions, bringing together science, engineering and community to scale up restoration in ways that are effective, inclusive and future-focused. Sean, thank you so much for joining us. It's a pleasure to have you here. It's great to be here. Yay, we have Sean on. So I think we should start off with a bit about your story. You've had a huge impact on the field of marine ecology. Can you tell us a bit about your journey? When you started, how you came to love the marine environment? I guess I started when I was about four or five years old, which is basically living beside the sea. My parents had a shack by the sea, and in summertime we'd go to the shack and I just was in the ocean all the time. I remember your mum telling me that you used to be hard to get to come home from the beach, so she'd just leave you there and you'd come home when you were hungry. That's right. I could actually keep being in the water and persist through the hunger pains because I was enjoying just being in the ocean so much, of course, discovered scuba diving and wondered how I could actually incorporate that into my working life. I had an interview with the Navy and I failed that interview and then it was my dad. He said, "Why don't you go to university, which never really crossed my mind?" And from there, I looked for opportunities to be able to work in the marine environment. And I just get bored easily, unfortunately. And so that led me to do things which other people weren't doing and what that actually did was create new disciplines, sub-disciplines. So for example, when everybody was doing very small local scale ecology at the Quadrat scale, I was working at Continental Scales. And now, that's not novel, everyone's doing that. And people would see my workers old hat. I've done that multiple times, living several projects as another one. And once people sort of start occupying the area, I've developed, I want to move on. That's amazing, Sean. So tell us a bit more about what a typical day looks like for you. You've obviously got a hand in science, but there's a whole lot of partnerships and some pretty cutting edge innovations. How do you balance it all? It's basically trying to get things right. I enjoy trying to solve a problem properly and a whole problem properly. And it means as I hit an area I can't resolve, I call somebody in who can help. I do a lot of research about who would be an appropriate person and then just really geek the whole thing out. So I am a science geek and I enjoy the pleasure, the expenditure of energy on getting things right. But within a much broader framework of actually delivering something that will make a difference. And when I say make a difference, I mean, producing science that will change a decision in the way that government will spend money or people will behave. Well, yeah, I think Sean, that you're a great case study of someone that is very willing to ask and collaborate for help when you need it. Because I think so often scientists sometimes try to do it as a sole, a sole pioneering effort. And we need to ask for help because everyone has expertise in different areas and you're really good at making sure that you call on the right people when necessary. Yes, I don't like working by myself. I think this is a personality trait. I really enjoy working at a problem with another person, rather than just me, my desk. Yeah, I'm the same. I wouldn't much rather work together. It makes it more fun. Before we get into too much detail about some of the amazing work you've done throughout your career in restoring kelp forest and am I right in saying seagrass meadows? You have worked in seagrass. So yeah. And also, of course, more recently, the oyster reefs, I thought just to get everyone on the same page because some of our listeners might not have that much experience with knowing what these habitats are and what they look like. So can you tell us about why these ecosystems are so important, not just from re-enlap and but also for people? They think of the kelp forests. They're the rainforests of the ocean. The seagrass meadows are paddocks. The oyster reefs are large reefs that produce habitats for fish to swim in and lay their eggs. They are the habitats which allow the whole ecosystem from the little tiny creatures of invertebrates. The plants that support them through to the fish that rely on them to actually produce the protein that we eat. That clean our seas oyster reefs are their filter feeders. They clean up water quality. In the old old days, we used to have very, very clear oceans around our coasts and that was primarily due to oyster reefs. So they helped the oceans in terms of their chemistry, their physics and their protein production. And of course, our enjoyment. People love going to clean places where it's teaming with wildlife, whether it's for recreation or just living next to it. I remember talking to people in the Anker Paringa just south of here. They'd never seen the oyster reef offshore that we had created, but they were in love with it just because it was there. Have you ever snorkeled with the giant kelp in Tasmania? Yes, I have. It's a magical cathedral experience. That's a big bucketless item for myself and I'm yet to do it, although cold. I've been diving in the kelp forests of the coast of New Sound, of the Atago Peninsula. Oh, they have them in New Zealand as well. Yeah, absolutely incredible. Just from the ocean floor to the surface. Yes, beautiful. Giant kelp, macrosisters, amazing. That's so special. So, I mean, on a bit more of a downside, I guess, what's happened to these habitats over the last few decades? Are they in trouble? Yes, globally. All three of those habitats in trouble, oyster reefs pretty much been knocked on the head globally, 85% of the original oyster reefs are now gone. Kelp forests are on the decline largely. We're coming back in some places where we've got oyster treating in the Arctic Circle, but in other places, or most other places, they're on the retreat. And the sea grasses have been lost globally as well. So, on a global scale, these habitats are in trouble. Wow. So, the oysters retreating and the Arctic allow in the kelp forests is kind of like rain shifting that we were talking about in the climate change episode, but the same with the kelp. Yes, so, they're limited by not having rock to be on. And where the ice retreats, that rock becomes available because the sunlight can penetrate. And they can grow there. Wow, that is really cool. So, Sean, you know, for bringing lots of innovation into the restoration space. And I'm thinking here, particularly around some of the work you do with sound to attract oyster larvae, but I'm sure there's others. Can you tell us a bit more about some of the experimental, surprising techniques that you're using for restoration? I think the playing music to restore the oyster reefs is a good example. It came from just anxiety. So, having discovered that we had lost hundreds and thousands of kilometers of reefs and convinced the state government that it would be a good idea that we could actually bring them back and all these benefits to both the environment and people. When we finally got the project started, I was started to worry about its success. I'd convinced myself it would be successful, but being the science nerd, I was really starting to worry about the finer details. And we had already gone to hatcheries and paid lots of money for them to brood up the stock. Remember, these oysters are largely missing now. There's a few out there, but they're functioning extinct. And I knew that there'd be 95% mortality, but didn't really anticipate it probably more. And in fact, the mortality was been about 100% from that brood stock. And knew that we had to find another way of being able to bring back these oysters. And how do oysters, which put out a little larvae, find our restoration sites? Well, they can use smell, they can use sound, and they've got little ice spots. So at the very last few centimeters, they can make small-scale decisions. But if you're trying to track our larvae from very large distances, it really is sound that they can key in on. And so I thought, we've got to find a queue, an navigational queue for these creatures to use sound. Now, the whole thing with oysters, larvae, so don't have ears. And this whole thing ought not to work. But it was reading something on the literature and speaking to people where there was enough biology that they might have in sensory organisms, organs, where they could potentially queue in on sound. And so it was a naive idea. It shouldn't have worked, and it does. It rewrites the basic book on how oysters larvae actually sense their environment and probably other invertebrates. And on the way, we learned a whole bunch of things about what actually makes up sound. And being very naive and hopeful went through the reality, the harsh reality that we knew so little about how this would work, but it does work. And it was great that we involved like Osotians, which was an engineering company that helped us make the underwater speakers. They went out there, dived, found fantastic data, undergraduates went out there, honest students went out there. So we had these independent avenues of finding out that these speakers were really working, those really repeatable work. And we could reproduce it in different places. And as a whole lot for science, it was really quite validating. So Sean, when you're talking about sound, you're not talking about playing the doors or lead zeppelin or something like that to attract the oysters. Where's the sound? What's the sound? We use sound from the existing kelp forests, which have the snapping shrimp. They split their fingers or their claws. And that snap that they make, which is the cavitation of creating little air bubbles that snap between the claws, is like listening to bacon being frying on a pan. And that's what you can hear when you go snorkeling. Is that crackling chorus? And we played that chorus back. And that was just our first attempt in the lab. We've subsequently found that there are better sounds to play that will induce better recruitment or settlement made him to be bassier sounds. So I suspect rock music might be a good light thing to have in our library. Imagine if that worked. I feel like that would be a great way to get some funding opportunities through. You could say, promote to ACDC or something that you're playing their music underneath and creating oyster reefs. And then you might be alright. to get some more fun. So I love the sound story, by the way, it's one of my favorite parts of the research that yourself and your colleagues here at the University of Adelaide and Abroad do. So marine restoration is often seen as slow or small scale, but your work definitely challenges that. What has enabled these bigger system level projects to succeed and what lessons might apply globally? It's a really thorny question is how do we take small scale successes and scale them up to coastal scales and the oyster reefs is just a world leader in learning lessons on how to do that. So when we lost the oyster reefs which were dredged out leaving sand behind, we had to put back the substratum and what we did with the government was decide that this should be done on an industrial scale. So we have 1.1 kilometer of reef over at New York Peninsula and that's been replicated on hectares scales and multiple other locations around South Australia. And that industrial scale approach gave us the confidence that we could do this at coastal scales. The big thing is that those industrial projects are not always going to be funded by government. They tend to be one off and large and we think the future is going to be where we have community led restoration. We have multiple communities, there's coastal communities all around Australia, all worried about their part of the coast, they walk their dogs, they go swimming in summertime, they're very keyed into the health of that environment. I think that's the army of labour and love that we need to engage to scale up whether that's putting rocks in the ocean or putting down underwater speakers and we need scientists to think about doing science which can engage with that labour and love and that's a different approach to doing academic science around restoration. So you've just been touching on the strong community component to the work but how do you bring those local communities into the restoration process? Perhaps you've touched on some of it but just briefly. Every little piece of coastline has a community and it has a school and a given example in Coffin Bay with Dom McAfee, he's been working with the local community, Indigenous community, the local school, the local tour operators, western farmers and has brought them together to actually go wow, we used to have oyster reefs here and there is a little old oyster reef that's still there, one of the only remaining ones in the whole of Australia and the school's gone out there and had a look at them and found that there's an enormous diversity of wildlife associated with it and they're wonder around that, it's really galvanised the community, got the kids excited about it, the parents get to learn about it, the tour operator can see that people are interested in it, they've been putting out new oyster reefs and experimentalised reefs to work out how we can go about restoring there and the community I think will be building the next large oyster reefs in that area. So it's about actually being there with the community and bringing the idea alive. Yeah, I love some of that work that Dom's doing over there as well, it's really cool. Yeah, bringing everyone on board is so important I think and then it's more successful as well because then if people they care about it because it's their backdoor and they're kind of backyard really for a lot of those people so having them on board I think is so important. We've talked about how the restoration has been quite successful but unfortunately a lot of this stuff costs a lot of money and I just wanted to ask you about some of the biggest barriers that you've seen in scaling up marine restoration in terms of funding and what we need to shift to unlock more progress. I think it's going to be in partnership between government and community led restoration so the government can also be a block and it's in this way in terms of the legislation and the rules around what can actually be done in the marine environment and what we're seeing is an open-minded approach is now realizing that communities are going to be a source of labour and love to do what they can't do, what the government can't do and as we're seeing them rewriting policy, looking at introducing new legislation, the funding would be in partnership with government whether that's councils or state government or federal government and you can do so much more with that free labour. It's surprising who's out there you've got people with boats and glass bottom boats in Coffin Bay who are extremely able to actually move tons of rock or transplanting of seeds and do this weekend and weekend out and that translates to millions of dollars worth of funding which you're getting as in kind support. So it's going to be a combination between the government allowing particular projects to go ahead in a very sensible way. We don't want this to become a new cowboy kind of activity for people in the weekends because that would not be good and having communities guide into doing sensible restoration with that incredible people power. That's very cool so there's another factor that's going to add a bit more complexity and that's climate change. How are you designing the restoration efforts such that they will survive or thrive under future conditions? I've been working with species which tend to be quite resilient that are quite capable of bouncing back. So oysters for example, they thrive. You see them actually on pair piling still colonised virtually anything so that's just a creature that has got a lot of resilience. Kelp forests give them the right conditions and we've done it here in South Australia with sea grasses. When our state on the back of our research invested about eight to $900 million on improving coastal water quality through the wastewater equipment upgrades of our sewage treatment plants over the last 15-20 years we've actually seen the recovery of both those habitats. Australia or South Australia leads the world in the amount of recovery of sea grasses and tens of thousands of hectares and kelps are coming back in South Australia where they're declining most other places in the world except the Arctic Circle. So by bringing the right conditions back which are local we can actually provide the environment where these creatures can come back and probably evolve as temperatures increase and acidity increases to cope with those gradual changes. Now heat waves are one thing which cannot be system back but they can recover from heat waves and I suspect what we'll see is nature is incredibly resilient and by offering good local conditions we enable them to come back and withstand if not bounce back from through resilience to persist through into the future. Well so we have a lot of listeners that we know are either young researchers in the field or maybe marine biology, marine ecology students that are studying marine biology or even higher school students that are looking to get into the career. Can you give any advice for those that want to get involved in coastal or marine restoration? Are there any skills or perspectives that you think are especially needed? Yes solutions in the environmental space requires good thinking, breadth of thinking, we call it multi-disciplinary thinking. People who are prepared not just to get wet but and get underwater or get the hands dirty but also prepared to learn things about how the human mind works. Why would people change their behaviour that's psychology? What are the benefits that's economy? One of the social benefits I'm working with social scientists and psychologists they being able to provide a convincing reason for why you're doing things and writing so being a good writer, being able to analyse things, being good at statistics, having a toolbox where you're actually able to do all those sorts of things and if you go to university making sure that you cast your net of courses very widely I think is going to put you in a much more employable position and a much more effective position. If you're a more effective individual you're going to bring so much more positive change to restoring the environment and as coastal communities then you are as a complete specialist or nerdy scientist that I used to be when I began. It's such good advice. I love that toolbox analogy, try to get as many different skills as you can because you're actually of the time to learn it and develop those skills while you are in undergrad or even doing a PhD you quickly run out of time so although you always have time to learn more but I can't even imagine you two compared to what I have, how many emails and meetings you both have on. Yeah well we won't go there but maybe I'm finally shown if you could leave our listness with one message about restoring ocean ecosystems what might that be? What actually gives you hope for the future? I think it's nature's incredible resilience. We could have. into that during COVID where everybody stayed at home locked up and all sorts of creatures emerged onto our streets that we thought would never venture out. And we saw creatures that people hadn't really seen before. The ability for nature to recolonize, to bounce back if we give it a chance is extraordinary and I am super surprised at how often this can happen and I think that there should be a little less climate despair because nature is a lot more resilient than we give it credit. Wow, what a great a great way to end. That brings us to the end of this episode. That was such a great chat. Thank you so much, Sean. Thank you for joining us on the ocean pod. We love being able to chat about all of the wonderful habitats, hug the South Australian coastline and also about how you're helping to restore them. Yeah, it was really inspiring. So thank you. I took a lot away from that. So if you've got questions, cool ocean facts or stories to share, hit us up on social media or through email. You can find our contacts in the show notes. We'd love to hear from you. And if you enjoyed this episode, make sure to follow ocean pod wherever you are listening to your podcast and leave us a review. It really helps more ocean lovers find us. Music written and performed by Sheamus Nicholas, graphic design by Rianne Vanneck. This podcast is produced by us Nina and Bronwyn, supported by the School of Biological Sciences at the University of Adelaide.