Hosted by: Alice Gage

Guests: Professor Tim Flannery, Sam Elsom and Dr Mariko Smith

Alice Gage: I’m Alice Gage, editor of the Australian Museum magazine. I’d like to acknowledge the Gadigal people as the Custodians of the land on which the Australian Museum stands. We pay our respect to Aboriginal Elders and recognise their continuous connection to Country.

This is Explore, a podcast that takes you inside Australia’s first museum. There are 21.9 million objects and specimens in the Museum’s collection, and each contains a clue from the past and an answer for the future.

Join us on expeditions, in exhibitions and in the lab as we delve into the world of the Australian Museum.

Sam Elson: I respect that it's an enormous task for us to get there, but it does give me a huge sense of hope that there are so many people in the world right now working on this challenge.

Mariko Smith: This knowledge is embedded and imbued in all objects.

Tim Flannery: I really want to focus on solutions because the solutions are where the power lies to inspire young people, to change government, to get industry working.

Alice Gage: Climate change is all around us – and not just the freak weather events that we seem to be enduring on a more regular basis. The ongoing media coverage and online chatter can feel overwhelming. So today, we’re exploring our landscapes and looking at solutions, and finding reasons for hope.

Tim Flannery: We really need to know where we are right now in terms of climate change. And sadly, we're not in a great place.

Alice Gage: Professor Tim Flannery is a Distinguished Fellow in climate change at the Australian Museum. In his 2021 Talbot Oration at the museum, Tim outlined his manifesto for humanity’s survival of the climate emergency.

Tim Flannery: And so we're at that fork in the road now where we need to turn things around. But, you know, since 2007, globally, we have produced about a third of all of the CO2, the greenhouse gas emissions that we've ever produced as a species. It's horrific the way that the problem just keeps on getting bigger and bigger and bigger.

So in terms of climate change, is there the equivalent of a vaccine? And they absolutely is. And if you want to understand what that is, I can do nothing much better than recommend you watch David Attenborough witness statement about his life on this planet. And, you know, towards the end of that witness statement, what he says is that what we need to do now is to restore Earth's function.

And he says that because the current climate system and the balance of gasses in the atmosphere is created by life itself, it's created by our forests and by our oceans particularly. So he lays out a vision of restoring our forests, of repairing the ocean.

We can see that damage occurring, and we need to be aware that the oceans, they’re the hidden puppet masters of the entire climate system, the oceans, if the oceans are healthy, the planet will remain healthy. So we need desperately to honour that vision that David Attenborough gave us of letting our Earth heal itself, restoring the forests, restoring the soils, restoring the oceans. This is not just a kind of an easy add on. This is a core business. And if we do that, we still won't have the full drawdown capacity we need. There are thankfully a few other options, and I've spent much of the last decade looking at these options, trying to work out where the most effective vaccine lies.

One of those options is seaweed farming.

Sam Elsom: It was actually through Professor Tim Flannery and through his role as chief counsellor of the Climate Council and tuned into a call and he was talking specifically about solutions. [...] And one was interesting to me was one of them was seaweed.

Alice Gage: Could I just ask you to say your full name and your title for us?

Sam Elsom: My name is Sam Elsom. And I'm the CEO and co-founder of Sea Forest and a company that's growing seaweed down in Tasmania.

Alice Gage: So you actually used to be a fashion designer. How did you get into seaweed?

Sam Elsom: Really, through climate change, you know, it was in 2017 the IPCC, released a report depicting some really quite scary graphs, actually on the just exponential rate of change that we were going to experience as a result of increasing concentrations of carbon dioxide in the atmosphere. And and just also illustrated the huge effort that was required if we were to have any impact on curbing that. And it occurred to me at that time that that we were doing nowhere near enough. So I became focussed on solutions.

Seaweed to me at the time seemed remarkably simple as a solution. But [...] when I looked around, I didn't see a hell of a lot of activity in the space. And so that's really where Seaforest was born. I began to to investigate all different varieties of seaweed that we have down here in Australia and and to understand what could be or could have the greatest potential impact, but also what could be the easiest to grow.

It was during that research that I discovered work happening up in Townsville with the CSIRO, where they were using… I think there was 30 varieties of seaweed and they were feeding them to livestock to see the impact on methane emissions and their methane emissions are the second largest contributor to greenhouse gas emissions globally. Methane as a gas having 28 times the warming impact of CO2.

They found that through that research, one seaweed called asparagopsis, which is native to Australia and New Zealand that could actually help virtually eliminate methane emissions from livestock. And so that was really exciting. But one of the bottlenecks at the time was that no one knew how to grow it. And so that became our focus, and that's sort of what Sea Forest does now down in Tasmania, we grow asparagopsis as well as a few other varieties of native seaweed.

Alice Gage: How does the seaweed work to abate methane in cattle?

Sam Elsom: So of all the 14, 000 species of seaweed asparagopsis, this is the only one that has this special sort of cell structure. It has small gland cells that look like little yellow sacks, and it's inside those gland cells that the seaweed synthesises all of these bioactive compounds from the ocean.

And it's those compounds that when fed to the cattle, they react with the enzymes and the microbial community inside the rumen. And they disrupt the production of methane. And in doing so, they improve feed efficiency. So essentially, what you're doing is through the avoidance of methane, you're creating more growth or more milk. And so you're getting an uplift in productivity. So not only are we having a positive environmental impact through the emissions reduction, but we're also increasing productivity for livestock farmers.

But just a very small amount of seaweed can be fed to livestock. So it's when we feed the seaweed to livestock, it's only 0.2 percent of their diet. So very, very small supplement that goes in with whatever else they're eating. And that reduces the methane emissions. And because [...] methane is 28 times the warming impact of carbon dioxide that has an exponentially greater impact on reducing emissions.

So one cow would produce anywhere from two and a half to four tons of carbon per annum. Feeding them just 10 kilograms of our seaweed in one year will virtually eliminate that amount of emissions. And so when you extrapolate that over the number of cattle in Australia, you can see there's a significant solution here and say in such a, you know, nature based solution.

Alice Gage: Sam has been lucky enough to team up with Rocky de Nys, a Professor of Aquaculture on the Sea Forest project.

Sam Elsom: Rocky’s special because he actually introduced that seaweed into the CSIRO livestock trials back in 2016. And the people in the world really who are experts in this seaweed all did a PHD under Rocky.

And we're very, very fortunate at Sea Forest to have, you know, a lot of those experts in seaweed working on the solution for us.

Sam Elsom: We've cracked the science and it does take science and asking questions of nature to solve these types of problems. [...] We couldn't be where we are if we hadn't solved that scientific question early on, and I think that's sort of part of the the why, why I have so much respect for Professor Rocky de Nys and his willingness to give up his position at James Cook University to join Sea Forest as full time is moved down to Tasmania with his wife.

And he's absolutely completely dedicated to the cause. As much as I'm giving my life to Sea Forest, he's as well. And there are others. But if we didn't have that science at the core of the business, we wouldn't we wouldn't have made much progress at all.

Alice Gage: Sea Forest is the only seaweed marine farm in Australia that’s commercially growing asparagopsis and using it as a fuel source for livestock.

Sam Elsom: It's a brand new industry and it's really exciting to be a part of a new and developing industry. But most importantly, I think it's really exciting because it's an environmentally positive industry. And also, we're operating in a regional part of Tasmania. I think that's really cool to me, providing employment.

So seaweeds rely on three basic things they need nutrients, carbon dioxide and sunlight. And so we deliver the nutrients in the carbon dioxide through the seawater. And unlike most land based systems, aquaculture systems that how effluent is cleaner than our intake. We have a, you know, almost like a sea water is more alkaline [...] with the increasing atmospheric concentration of CO2 has led to an increase in the acidity in our ocean. So we need to reduce the amount of carbon in our ocean and seaweed is a great way for us to do that.

But what I think is really special with being able to scale this solution in terms of climate change, and seaweeds can be a carbon sink, so through photosynthesis, they draw down enormous amounts of carbon. They grow really quickly because they're completely immersed in their food source. And then ultimately, 40 percent of the biomass that we harvest is carbon that's captured from the marine environment.

We have to keep talking about it, we have to bring these kind of tangible things to market. [...] As soon as people start seeing an option on the supermarket shelf for example people need something tangible. And I think it then start to sort of see the potential.

It's a very exciting industry to be developing, but it's all new. So I think the world will be ready. It's just going to take some time.

Alice Gage: Even though the consumer market might not be ready for seaweed, Sam’s seeing a strong interest from a bunch of massive brands and companies.

Sam Elsom: We've had a lot of really exciting projects happening over the last two years, so we've been working with not just cattle, so the seaweed works on all ruminants. So any animals with four stomachs and they are sheep, goats, cows, you know, someone told me the other day, even giraffes have four stomachs.

We've been working with a sheep farmer wool farmer down in Tasmania who's been supplying to the tailoring Australian tailoring brand MJ Bale. For the last two years we've been working with those guys and they're now producing what they’re calling net zero knits and carbon neutral suits, which is really exciting. And we've also been working with a company called Fonterra, which produces mainly dairy products. And so they've been feeding it to their dairy cows, also on farms in Tasmania and and looking at, you know, what the impacts are on milk flavour and milk production.

In the beef industry. We've got a number of different trials underway at the moment with universities to validate it in a much larger scale, the the abatement. And as well as that, we've got a world first trial with major pastoral company AA Co. So that's really exciting and also a great grass-fed trial with a company, a burger company called Grill'd. So there's lots of really exciting things happening, and I think what I've been most inspired by is just the way that the in the whole industry is shifting in the way that they're thinking about climate change. In the short time that we've had Sea Forest, we've really seen that shift, you know, the level of engagement and farmers are keen to adopt.

You know, I think that that there's never been a time on this planet when there's been more people focussed on. You know, climate change and finding solutions to climate change and whether it's through renewable energy or technologies like growing seaweed or direct air capture, or there's never been a time where there's been so much innovation focussed on creating positive environmental outcomes. And I think, you know, focussing our energies in that direction, I think, gives me a lot of hope that we're on the right track to kerb, the warming. I think, and I respect that it's an enormous task for us to get there, but it does give me a huge sense of hope that there are so many people in the world right now working on this challenge.

Alice Gage: Tim Flannery suggests that when thinking about how we can better manage and maintain our environments, we have a lot to learn from Aboriginal and Torres Strait Islander peoples.

Tim Flannery: We have had two centuries of pioneering destruction of our environment behind us.

And we heard in our welcome to country that about that very different relationship. And the offer was made from our indigenous leaders to go on the journey with them, to start using the land differently, to start living differently on the land, envisaging it differently.

That needs to become our lore. If we want to start repairing our planet we can do it bit by bit. It's going to be a long journey. It's going to be a hard journey, but we can't really expect a great outcome without it.

Alice Gage: Dr Mariko Smith is a Yuin woman with Japanese heritage and she is Manager, First Nations Collections & Engagement at the Australian Museum.

Mariko Smith: Walawaani njindiwan. That is “Hello, everyone,” in the Dhurga language of the South Coast of New South Wales. I would like to acknowledge and pay my respects to the people and other beings who keep the lore of this land to the elders and traditional owners of all knowledges, places and stories shared in the Australian Museum and to the ancestors and the old people for their resilience and guidance. And from wherever you are listening to this podcast, remember that you are an Aboriginal land and acknowledge the Aboriginal custodianship forever embedded in country.

Alice Gage: So the Australian Museum recently acquired the Kimberley Boab nut collection, could you just tell us what are boab nuts and. And could you maybe describe what's carved or painted on them?

Mariko Smith: Boab Nuts so they're nuts from the Boab Tree is part of a carving practise that is specific to the Kimberley region of Western Australia. And it's highly significant to First Nations communities because boab nuts are utilised in a not only as a source of bush tucker and bush medicine, but also as a way to pass on cultural knowledge and also a way to create income through selling carved boab nuts for tourism.

It's similar to the carving of emu eggs in the southeast of Australia in that, boab nut we carvings, our visual representation of cultural knowledge and a way to document life events and stories in the Kimberley region.

And, you know, provides an alternative form to coincide with traditional practises of carving cultural knowledge on objects made of wood. So, for example, you know, shields and boomerangs. And community from the Kimberley have told us that, you know, stories are told through the Boab Nuts and Boabs are special, particularly because they only grow in the Kimberley region.

Alice Gage: 265 boab nuts are featured in the collection, illustrated by 85 artists.

Mariko Smith: So this is a culturally and historically significant collection of carved and painted Boab nuts specific to the Kimberley region of Western Australia. And it had been offered to the Australian Museum as a donation in 2021 from Nicola Daha. And this collection is a valuable addition to the museum's cultural collection, especially given the detailed provenance of the objects. The identification of the artist there's 85 plus artists featured in this collection, as well as the historical and cultural significance of Boab nut carving and painting from that region.

And since 2010, the donor of the collection had been collecting carved and painted boab nuts directly from prominent Aboriginal artists from across the Kimberley region.

[...] and the artists include well-known names like Marion Cox, John Whera, Melissa Carroll, Allan Carroll and Katrina Bedford.

So just to give you a bit of a profile on one of the artists featured in this collection in the summer 2022 edition of the Museum’s Explore magazine, we feature a beautifully designed boab not titled Bush Plum, in reference to the image of the bush plum plant painted on it by artist Marion Cox. So Marion is a highly respected and award winning senior artist and knowledge holder from the year yearly community that is located 110 kilometres west of Halls Creek in the Kimberley region. And her culturally informed art practise speaks to the stories of country in the patterns used on her. Both have nuts often focus on bush food and bush tucker.

Alice Gage: It’s incredibly important for the Australian Museum to acquire collections like this, for a range of cultural and historical reasons.

Mariko Smith: We really wanted to emphasise as we acquired this collection that strong cultural and documentary significance of the boab nuts because in a community, many community in members in the Kimberley do boab nut carvings.

And these objects, you know, they provide a sort of visual representation of of culture, as well as documenting links to early trade with colonists, you know, as a way to attain income, but also develop that relationship for gifting of these carved and painted boab nuts.

And so these are very much, you know, also a testament to First Nations small enterprise and as the donor mentioned to our cultural collections team, and will be good to keep the collection as a historical record for future generations. It's a picture in time of generations adapting to modern lifestyles and a record of the artists of various families and language groups.

[...] We very much focussed not just on historical collections, but is also important to acknowledge that Aboriginal and Torres Strait Islander cultures are dynamic. They're always changing and adaptive to various conditions. So it's important to also focus and highlight contemporary indigenous cultures and peoples. And so this collection, you know, provides the Australian museum with the opportunity to celebrate and reflect on that ongoing dynamism of First Nations culture.

Alice Gage: Mariko, why is it important for the Australian Museum to share the First Nations Collection with non-Indigenous visitors?

Mariko Smith: They have so much to teach us. With the objects that have been collected over the last two centuries, it's interesting to look at some of the older material and to compare it to more recent contemporary examples. And I'd like to draw listeners attention to the Tasmanian shell necklaces because when you have a look at some of the older examples of shell necklaces from like the 1800s early nineteen hundreds periods looking at the size of the shells, the type of shells that Imagineer shells, for example, there's so many different types. There's beautiful, pearly limit, luminescent sort of. Cells in a smaller ones that are like you got black white in different colours.

But what I find with the more recent shell necklaces that are still being made by Tasmanian Aboriginal women, that cultural tradition is still continuing strong. But what I've heard from the women is that it's getting harder for them to harvest the shells. The women have to venture further offshore to harvest the shells and also the shells. They can be smaller than what they have been in the past, and so you can see direct impact on the sourcing and also the appearance of the shells.

What we can achieve by reviewing, you know, historical objects with the more contemporary objects that are still, you know, continue to be made by First Nations communities in that continuity of cultural practise is that, you know, within a very short period of time. So you're looking at like, you know, two hundred and fifty years or a little bit less than that, you can see there's been a dramatic change in the environment and in the natural resources over this very short period in comparison to, you know, the longer occupation of First Nations peoples. And so we can see a lot of change happening within the last few decades, if not the last 200 years.

I think the clear message here is about understanding your local environment and conditions, so it's about practicality and sustainability of having a deep respect and awareness of what is available in your local environment and ecosystem. So that's like, you know, that defines many of our cultural practises. Is that deep respect and knowledge of of your local environment.

Alice Gage: You can see images of the Boab Nut Collection and find extra resources and stories about Sea Forest and climate actions by going to

Coming up on our next and final episode, we’re taking you into the field to introduce you to some of the world’s most recently discovered species.

I’m Alice Gage, editor of Explore magazine. This episode was produced by myself and Cassandra Steeth, edited by Bernadette Phuong Nam Nguyen (Foong Nam Ween) and mixed by Weronika Razna. Our music was written and performed by Freya Berkout. Bye for now.

If, like us, you’re anxious about the climate emergency, tune in: this episode is all about the gaining of wisdom in an uncertain world. We look to science, innovation and First Nations knowledges to learn how one young Australian is detoxifying the ocean and atmosphere, and what the world’s oldest link between humans and the land can teach us about managing the environment.

In his 2021 Australian Museum Talbot Oration, Professor Tim Flannery calls for solutions. One of those is floating out at sea – a native seaweed called asparogopsis, which when fed to cows substantially reduces their methane emissions.

Another solution is listening to First Nations Peoples, whose successful stewardship of Country for time immemorial saw both people and the environment thrive. Australian Museum First Nations curator Dr Mariko Smith discusses what one new acquisition – the Kimberley Boab Nut Collection – can teach us about this legacy.

About the guests

Professor Tim Flannery

Professor Tim Flannery is the Distinguished Visiting Fellow focused on researching the impacts of climate change and raising awareness of the issues, especially impacts on biodiversity and our coastal environments. He is an internationally acclaimed scientist, author, explorer and conservationist.

In recognition of his work on the Climate Commission and the Climate Council, he was recently awarded the Geddes Environment Medal by the Royal Scottish Geographical Society. His latest book, The Climate Cure: Solving the Climate Emergency in the Era of COVID-19 (Text Publishing, 2020), is available to buy online at the AM Shop.

Climate change leadership team

Professor Tim Flannery, Distinguished Visiting Fellow focused on researching the impacts of climate change.

Image: Abram Powell
© Australian Museum

Dr Mariko Smith

Dr Mariko Smith is a Yuin woman and Manager, First Nations Collections & Engagement at the Australian Museum. Mariko focuses on Indigenous community-based cultural resurgence initiatives and incorporating Indigenous ways of knowing into curatorial and artistic practices.

Mariko holds a combined Bachelor degree in Arts and Laws (University of Sydney), a Master of Museum Studies (University of Sydney) and Doctor of Philosophy from the Faculty of Arts and Social Sciences (University of Sydney). Her PhD thesis focused on the cultural resurgence of Aboriginal tied-bark canoe making in south-eastern Aboriginal communities. Mariko is an Honorary Associate in the School of Literature, Art & Media at the University of Sydney.

Dr Mariko Smith in Unsettled

Dr Mariko Smith is a Yuin woman and Manager, First Nations Collections & Engagement at the Australian Museum.

Image: Anna Kučera
© Australian Museum

Sam Elsom

Sam Elsom is the founder and CEO of Sea Forest. He is a passionate environmentalist with over 15 years’ experience in sustainability.

Having founded one of Australia’s first sustainable apparel businesses to measuring social and environmental impact across supply chains as well as implementing a satellite factory in India to support poor communities with income, training, clean water and education. Sam was drawn to explore seaweed cultivation for its impressive capacity to sequester CO2 as a potential solution to reverse Climate Change.

Dr Rocky de Nys and Sam Elsom from Sea Forest

Sam Elsom, founder and CEO of Sea Forest.

Image: Supplied by Sea Forest
© Sea Forest


Alice Gage is the producer, writer and host of the Australian Museum’s Explore podcast, and editor of Explore, its biannual magazine.

Alice is an editor, project manager and content creator with 15 years' experience in print and digital storytelling. She is a passionate communicator of science, intersections of culture, climate change, the arts and parenting, working across a broad range of formats. She founded and published cult art journal Ampersand Magazine from 2009-2013.

Alice lives on Bidjigal Country with her husband and their two little redheads. She holds an MA in Communications from Melbourne University and a BA in English from Sydney University.

Alice Gage - Digital Communications Coordinator

Alice Gage is the producer, writer and host of the Australian Museum’s Explore podcast, and editor of Explore, its biannual magazine.

Image: Supplied
© Alice Gage