Blue Revolution: Regenerative Ocean Farming With Bren Smith

In this first of a two-part program, we take a deep dive into regenerative ocean farming, an extraordinarily productive and low-impact way of producing vast quantities of food for a growing population. It has the potential to re-make agriculture from the bottom up, while regenerating oceans, farmlands, farmer livelihoods, and the climate.

To listen to the second part of this program click here.


Bren Smith, co-executive director and co-founder of GreenWave and owner of Thimble Island Ocean Farm, pioneered the development of regenerative ocean farming. Bren is the winner of the 2015 Buckminster Fuller Challenge award. He is an Ashoka, Castanea, and Echoing Green Climate Fellow and James Beard Award-winning author of Eat Like a Fish: My Adventures Farming the Ocean to Fight Climate Change.


  • Executive Producer: Kenny Ausubel
  • Written by: Kenny Ausubel and Arty Mangan
  • Senior Producer and Station Relations: Stephanie Welch
  • Host and Consulting Producer: Neil Harvey
  • Producer: Teo Grossman
  • Program Engineer and Music Supervisor: Emily Harris
  • Production and Engineering Assistance: Rebekah Wineman
  • Production intern: Isabelle Dean

This is an episode of the Bioneers: Revolution from the Heart of Nature series. Visit the radio and podcast homepage to find out how to hear the program on your local station and how to subscribe to the podcast.

This program was made possible in part by Guayakí Yerba Mate, working with Indigneous farmers in South America to grow shade grown, organic yerba mate. To inspire us all to come to life. Learn more about Guayakí’s products and regenerative mission at

Subscribe to the Bioneers: Revolution from The Heart of Nature podcast


NEIL HARVEY, HOST: As climate disruption bears down, our food system is one of our greatest vulnerabilities. Land-based agriculture in its current form will not survive global weirding, bedeviled by extreme heat, droughts, floods, freshwater scarcity, and overall erratic weather patterns that are all over the map – literally. And in many cases, it’s conventional agriculture itself that’s worsening the very conditions that will topple it.

Something’s gotta give. Starting with the underlying paradigm.

In an iconic 1981 essay, the esteemed writer and farmer Wendell Berry wrote that the key to overcoming our escalating agricultural crisis is what he called “solving for pattern”.

It’s a solution that addresses multiple problems at once in a self-reinforcing way by addressing the larger pattern of the entire system. It’s a solve-the-whole problem approach. 

What makes Bren Smith’s regenerative ocean farming model innovative is that it solves for pattern. At the same time that land-based farming faces extreme systemic threats, if the fishing business continues as usual, many ocean fisheries are projected to collapse by 2050. 

Regenerative ocean farming offers a breakthrough pathway for addressing these twin crises. This type of marine-based farming, known as mariculture, is an extraordinarily productive and low-impact way of producing vast quantities of food for a growing population. 

Simultaneously, this regeneration revolution aims to redesign the food economy away from destructive profit-driven practices and agribusiness monopolies in favor of democratizing the food economy.

And that’s just the foam on an ocean of possibilities…

Bren Smith is the co-executive director and co-founder of GreenWave, a non-profit that trains and supports regenerative ocean farmers. We spoke with him in an online conversation.

BREN SMITH: Our land-based food system is being pushed out to sea, right, whether it’s droughts, wildfires, the lack of nutrients in the soil. Like, we’re going to have to get more food from the ocean. I think there’s no question about that. But our oceans’ wild populations can’t bear the brunt of that. Ninety percent of fish stocks are either over fished or fished at their limits. Like we need to actually roll back—the impact of industrial fishing.

Bren Smith

HOST: A fisherman is all Bren Smith ever wanted to be. Born in Newfoundland, Canada, he headed out to sea when he was 14 after dropping out of school. He fished in Gloucester and Lynn for tuna and lobster, and later shipped out to the Bering Sea for many years. 

Then the cod stocks crashed. It triggered the biggest layoff in Canadian history with 35,000 people thrown out of work. 

Bren watched fishermen wandering the streets like displaced persons – boats beached, canneries dead empty. 

He saw that industrial fishing operated by essentially clear-cutting entire underwater ecosystems, while chasing fewer and fewer fish further and further out to sea. He knew there would be no jobs on a dead planet. 

That blood-chilling experience jolted his relationship with the sea. He looked to conventional aquaculture, but realized it was the wretched analog of putting Iowa pig farms on the sea.

BS: I mean I was so excited to go farm fish, because I was told this was the future; we were going to feed the planet; and it was just like this hotbed of learning. But then I got out to the farms and it was really, really heartbreaking, using pesticides, antibiotics, fish [SOUNDS LIKE: brakes]. The fish tasted terrible, they looked terrible, and…I think the aquaculture industry at that time, although it’s really tried to make improvements, there are a lot of good folks really trying to innovate, but it chose the wrong thing.

Aquaculture did not ask the ocean: What does it make sense to grow? What it did was it asked the market, and what the market said at the time was everybody likes to eat salmon and tuna. Why don’t you grow salmon and tuna? And what we need to do is flip that and ask the ocean: What does it make sense to grow, what’s unique about the ocean as an agricultural space?

And you ask that, and the ocean says: Why don’t you grow things that you don’t have to feed and don’t swim away. And I think that was then my journey. Let’s grow as many of those species as possible, and that’s how you get to regenerative ocean farming at the end of the day.

HOST: Synchronicity struck. When New York’s Long Island Sound re-opened to oyster farmers in order to attract young people into the shell-fishing industry, Bren started Thimble Island Ocean Farm to grow oysters off the coast of Connecticut. Again, he encountered new secondary problems and had to change course…

BS: God, was I a bad oyster farmer. [LAUGHTER] Like really bad at it. I mean, I killed millions of oysters my first couple of years, because it was psychologically such a different thing. Like I’m a hunter-gatherer in my nature, and suddenly I was floating around in the same 20 acres, you know, supposedly cultivating these little creatures. And I found it boring at first. I was like: Where are the rogue waves? Where’s the excitement? But eventually, I just fell in love, like developing the blue thumb, just really watching the winds and waves on this small patch of water, and just knowing every inch of it every season. There’s a real thrill to that.

You know, I’d been oyster farming for about seven years, was very successful because I was close to New York. It was sort of the emergence of the boutique sort of Brooklyn oyster scene. Right? And that’s where I really learned to think and appreciate food, because I’m both not an environmentalist but I’m not a foodie either, I like to eat at the gas station, is my favorite.

The oyster company was doing really well. And then Hurricane Irene and Sandy came in, and that was two years in a row hurricanes destroying my farm, two years in a row. And one year is one thing. You’re like, Oh, terrible, but let me pick myself up, start again. You get hit two years in a row, 90 percent of your crop gone, over half your gear destroyed, and you realize that this is the new normal.

Climate change at that point was supposed to be a slow lobster boil. It was going to be a 100-year-off problem. And the environmentalists and public policy people were talking about it, like, let’s protect it and save our children. And suddenly I was the canary in the coal mine. It was like, No, this is about my farm, my boat, my livelihood, and it’s right now.

It was depressing. I’ve got to be honest. That moment, I think, was the best moment of my life, where out of the negativity and the hopelessness sort of bred a new opportunity, you know. Our backs are against the wall, very often humans do their best thing. So that’s where I started.

HOST: Meanwhile, climate chaos was becoming a faster lobster boil. What to do? The swelling human population is projected to need 56 percent more food to feed nearly 10 billion people by 2050. And just 7 percent of existing fisheries can handle any more fishing at all.

His back to the wall, Bren Smith landed an epiphany.

BS: What I did was, okay, the storm surge comes in, buries all my crop, let’s move off the seafloor and use that entire water column, and let’s grow as many of these species that are similar to oysters as possible.

And we have all these species, there are hundreds of kinds of shellfish, 10,000 different seaweeds that’s possible to grow. I mean, imagine being a chef and finding there are arugulas, tomatoes, kales that you’ve never seen, tasted, or cooked with before. Right? So suddenly what becomes this very depressing story becomes a story like an entirely new climate cuisine, which taps into the creativity, I think, of one of the great culinary moments in American history, which is right now.

The other thing, it’s like, who’s going to eat seaweed. Right? And that’s one of the core questions. Shellfish is much easier. All our collaborative chefs that are making things delicious, like barbecue kelp noodles with parsnips and bread crumbs – like this delicious way to make a vegetable a little unhealthy and also really like unravel our associations with seaweed. It’s just a delicious dish.

You know, as I dove into this, what I found is that, yes, we can do this as food, but tastes change slowly. What’s powerful about kelp is that it can be used in so many different ways. Right now we’ve got a “whole leaf” strategy. And just from my farm, last harvest season, the stems we turned into kelp pickles. The next set of the stem we turned into kelp flour and used it in plant-based burgers as well. Right? So that’s the ingredient. Then we don’t have any waste because we’re planning ahead.

HOST: Beneath the surface, regenerative ocean farming is a real-life Octopus’s garden. At an event hosted by ABC Home in New York, biologist and author Ayana Elizabeth Johnson interviewed Bren Smith and asked him to describe what a 20-acre farm looks like.

Ayana Elizabeth Johnson and Bren Smith

BS: Imagine an underwater garden, right, and you’ve got hurricane proof anchors on the edges, then you’ve got horizontal ropes connecting these anchor systems. It’s just a rope scaffolding system under water. And from there we grow our kelp vertically downwards. Our mussels, our scallops, and lantern nets, and then cages down on the bottom, and clams in the mud. And the idea is just to figure out how many different species we can grow in 20 acres. This is really permaculture of the ocean.

AYANA ELIZABETH JOHNSON: The mussels grow in a sock. Could you just explain a mussel sock for those who may not be familiar?

BS: Sure. So when we see the kelp, and after we harvest it, there are the little stipes left over on the rope. Right? And mussels love those little stipes that are left over. And—

AJ: Stipes are seaweed stems.

BS: Yeah, seaweed stems. Exactly. And so the mussels stick to all those stems and grow out. We then rip the mussels off, and we put them in these socks. Sort of like make sausages out of them.

And then we hang them back on the kelp line. And the idea is we can use the same gear, we can rotate crops, and just keep growing year-round…

AJ: So you’ve got stuff in the mud, you’ve got stuff on the mud, you’ve got three different things hanging and growing, and then you have different things that you’re growing in different seasons. So, it’s a year-round scenario. How many tons comes out of one of these small farms?

BS: It’s about 10 to 20 tons of seaweed per acre and about 250,000 shellfish per acre.

HOST: Bren Smith shows how we can sustainably harvest massive quantities of protein and nutritious vegetables from the seas in ways that also restore coastlines, communities, local economies and the climate. 

When we return, Bren rocks the boat by demonstrating regenerative ocean farming’s mighty potential to sequester carbon and restore ocean ecosystems.

HOST: Regenerative ocean farming is a textbook model of solving for pattern. It flips the extractive paradigm into a paradigm of regeneration – from vicious cycle to virtuous cycle.

One of the biggest challenges farmers have faced for decades in scaling up organic farming is getting enough organic fertilizer and compost. The supply just isn’t there. 

Bringing that fertilizer from the ocean to the land can help meet the needs of farmers in an ecologically beneficial way.

Kelp provides rich fertilizer for soils, and healthy feed for animals. Feeding kelp to cows and sheep is not only very good for the animals’ health, it reduces their climate-crashing burps of methane emissions by a jaw-dropping 80 to 90 percent.

BS: I was at the Al Gore’s climate underground, all about regenerative farming. I was the only ocean person there out of like 2-300 people, and everybody was complaining and up in arms about the nutrient crisis. Right? Like our soils are dead and we really need more nutrients. And I was like, I’ve got them all. They’re in the oceans, that nitrogen, and the phosphorous, all the micronutrients. So let’s use things like kelp to soak those up and bring them back to the soil, right? Create a virtuous nutrient loop; let’s build a bridge between land and sea.

There is a long history of using seaweeds as fertilizer and feed. In fact, in the banks on the docks of San Diego in the early 1900s, there were 1500 workers producing fertilizer and feed out of kelp – it was wild kelp at that point – for up to a thousand land-based farms in the Midwest. I say this is something we’ve done, it’s just, you know, corporate, industrial ag, you know, with fertilizer, with soy, with things like that have just pushed it off the table in terms of one of the tools that are out there for farmers to farm regeneratively. So I think there is a huge potential there.

HOST: Kelp can also be made into compostable plastics and biofuels. An area the size of the state of Maine could replace all the oil in the US, according to the US department of energy.

As climate chaos continues stressing terrestrial farming, regenerative ocean farming can mitigate and start reversing some of the most catastrophic effects.

Here is Bren Smith again, with biologist Ayana Johnson.

BS: Our farm, for example, soaks up nitrogen, the seaweeds soak up carbon. Kelp is called the sequoia of the sea. It soaks up five times more carbon than land-based plants. One journalist called it the culinary equivalent of the electric car, which is a beautiful phrase. The farms function as storm-surge protectors and artificial reefs that just attract all these species that come hide and thrive

I mean, my area, when I first came into farm, it was a barren patch of ocean, and now it’s a thriving ecosystem.

AJ: So how big a deal is the fact that as the kelp grows it’s absorbing tons of CO2. Like obviously we need to be drawing down carbon and absorbing it and sequestering it. Photosynthesis is like the most underrated climate solution, in my opinion, so shout out to photosynthesis. [LAUGHTER] How big an impact does it make? Like sure, it absorbs CO2 like all plants do, but at what scale does that help? Because we’ve got a pretty big climate crisis on our hands.

BS:  Yeah, absolutely. I mean, the World Bank did a study, and they said if you take less than 5 percent of US waters, you could sequester the amount of carbon put out by I think it was 120 million cars, create 50 million jobs, and the protein equivalent of three trillion cheeseburgers. Right? So this is scalable.

HOST: All of these benefits make Bren Smith hopeful that regenerative ocean farming can be implemented on serious scales to address climate disruption and ecological degradation – and to solve for pattern in self-reinforcing cycles of mutual benefits.

BS: Kelp is the rainforest of the sea. And the oceans have always played this central, regulatory role on the planet. Right? I think they’ve soaked up 90 percent of the excess heat and 30 percent of the carbon put out by humans has been sequestered by the ocean. And kelp is one of the sort of heroic plants in that process.

We think of it as blue carbon. It just makes it really powerful. So the kelp sequesters carbon. The oysters and shellfish play this really important role in the nitrogen cycle. So an oyster filters up to 50 gallons of water a day, and they feed on nitrogen, that’s what they do. And so that’s incredible, because this sort of Mother Nature’s technology is filtering that nitrogen out of the water column, and land-based farming as well as other things is creating over-nitrification in our oceans. And if you get too much nitrification in the ocean, you get dead zones.

So there are these massive zones all over the globe where nothing is alive. There’s not enough oxygen. Just everything’s been killed off. Oysters are really the sort of warriors against that.

There was a study on the Pacific Northwest that surrounded an oyster farm with kelp, and they found something called the Halo effect. Inside that kelp halo, the acidification rates were much lower than outside. Right? These are just powerful technologies that Mother Nature has given us.

HOST: A ground-breaking study by The Nature Conservancy and the University of New England has provided strong evidence that shellfish and seaweed farming are a critical component of regenerative food production.

And the kelp grows fast – as much as a foot per day. Its structure fosters a sanctuary for biodiverse marine life without excluding human interaction.

BS: Mother Nature hates monoculture. Right? You grow a single species in density. You know, if you had a kelp farm that was a thousand acres, Mother Nature would attack it. Right? If you just grow salmon, Mother Nature attacks it all the time. What we want to do is mimic and grow all these species together and do what she does well. Right? And the benefit of that is that all the species are working together on the farm, and it creates an entire reef for other creatures. Right? So it’s a foundational system to rebuild reefs, the farms are. That’s sort of a whole package of benefits that the farming model brings.

The other thing is like, we seed the farms, and then all our crops send more seed into the natural environment. We only use native species. And so, yes, we’re farming and harvesting, but we’re overproducing, and so rebuilding that ecosystem all around us.

I think that’s what – one of my frustrations, honestly, with part of the environmental movement is that it’s obsessed with conservation. Right? So we need to set things aside—so like, for example, take the ocean and create marine parks. I think what they don’t understand is that in the era of—Or maybe they understand but aren’t sort of really grappled with is we could set aside the entire ocean as a marine park, and it’ll die because of climate change.

And so instead, what we need is ocean farms and other things that are akin, breathing life back into these ecosystems. So as ocean farmers, we’re actually helping the ecosystem heal and rebuild. And I think the marine park of the future looks like, take 2,000 acres, right? And you’ve got farmers farming on part of it. They’re doing reforestation on another part, just planting kelp and shellfish, right, with the same skills they have, but not harvesting it. Then you’ve got artisanal fisheries and eco-tourism, and that’s what a marine park of the future, as opposed to this place where you’re never allowed to go and we just slowly let die.

HOST: By mimicking nature’s playbook, we can help nature heal itself – and set in motion a virtuous cycle of regeneration. In this paradigm, human beings are no longer the bad guys.

In truth, Indigenous peoples have long held this kind of knowledge. 

When the Europeans first set foot on North America – what the First Peoples call Turtle Island – they saw a vast, undisturbed wilderness of endless bounty. In reality, there were about 100 million Native Americans living there in a vast thriving landscape they actively cultivated with extraordinary sophistication, including farming ocean oyster and clam beds. 

The Coastal Miwok in what’s now San Francisco’s Bay Area maintained clam beds for centuries. Then the Forest Service declared the area a preserve and told the Miwok people they couldn’t harvest clams anymore.

The Miwoks asked: “Don’t you understand? The clams know we’re coming. If we don’t come, they’ll die.” 

The Forest Service summarily dismissed their plea. Then the over-populated, untended clam bed began to fail and died.  

What the Miwok had been consciously doing was the equivalent of weeding a garden. They had sustained the beds year after year for centuries. 

GreenWave’s regenerative ocean farming model further serves to detoxify waters. Since so-called “waste” doesn’t exist in nature, it becomes a game of mixing and matching organisms to create desirable food webs. It’s a process to clean water and soil that’s called bioremediation.

As a powerful bio-accumulator, seaweed absorbs pollutants as well as excess nutrients. For decades, the mining industry has used bio-accumulator plants to remove heavy metals from sites poisoned by surface mining. It’s then possible to reclaim and recycle the metals from the plants.

BS: So we really see our farming working in multiple ways. We have farming for food, and the key is shellfish are the most traceable regulated food in the country, because it’s a live product. So we’ve incorporated our seaweed into that regulatory regime. Like you wish your arugula was as traceable as our seaweeds and shellfish. So regulation traceability has been key on that.

We also grow in polluted waters on purpose, just to soak up heavy metals, to rebuild those reefs. So we had a farm with Dr. Charlie Yarish in the Bronx River, for example, and that was just to do ecosystem services, right, to rebuild that. We’ve got another farm we’re working with the Port of San Diego in California.

And then the other thing is like we can just—the same skills for farming are required for food as they are with reforestation. So because we can use our seaweeds to draw down that carbon, if we even say someday we can’t eat it, it still has a role. Like we need to create the hatcheries and the skills to get people out there replanting the world’s rainforests underwater essentially.

As public policy moves forward, if it moves the wrong way, maybe someday I’ll just be the Johnny Appleseed of kelp out there all day. That’s fine. I still get to die in my boat, right, and that’s the goal. But hopefully society will get its act together before that.

HOST: After decades of destructive farming practices and inaction on changing misbegotten policies and practices, global weirding is escalating the stakes. Massive change and mounting ecological disruption are inevitable. It’s not a question not of “if” everything’s going to change – but “how”.

In this time, says Bren Smith, it’s all power to the imagination and all hands on deck.

BS: I feel desperate at a personal level, and I think a lot of folks I know, that we need a new story to tell ourselves, right, for this new era. Sort of we’re saying goodbye to one world, and we’re just in a period where we’re being introduced to a whole new one.

I think there’s opportunity out in the ocean in a major way. Forty percent of our country lives on the coastal communities. Like head out to sea and get to work. And that doesn’t mean, you know, like I do, farming in the winter and breaking ice off the gunnel. Go into public policy and help us shape really progressive powerful legislation that protects communities. Right? Go build a hatchery in your basement to create a community garden locally, right, where you’re welcoming folks out to grow their own food. Start clam gardens so community members can come down, harvest the clams, and feed themselves. Be a place for food security.

There are a lot of ways to engage. And certainly there are just so many open questions and challenges that we face in this industry, that we need all sorts of creative thinking.

HOST: Bren Smith is riding historic tides of change. In part two of this program, we explore the once-in-a-civilization opportunity to use regenerative ocean farming to remake the food economy – from the bottom up – the bottom of the ocean.

Keep Your Finger on the Pulse

Our bi-weekly newsletter provides insights into the people, projects, and organizations creating lasting change in the world.