Meet the ocean scientist making waves
Dr Masa Tatsumi is a seaweed scientist actively cultivating a solution to climate change.
I’m standing beside Dr Masayuki “Masa” Tatsumi, head of research and development at Sea Forest, alongside a neat row of above-ground tanks filled with seaweed. These high-rate algal ponds are informally known as “raceways”, Dr Tatsumi tells me. Each sports an enormous whirring paddle that sends water circling like a car around a racetrack.
“They’re my babies,” he says, admiring the crimson-red pom pom-like puffs of seaweed tumbling in the water. Officially known as asparagopsis, this common seaweed – which is native to Australia – is the key ingredient in SeaFeed, an oil-based supplement that reduces the amount of methane produced by cows.
“We are cultivating a solution to climate change,” Dr Tatsumi says. “[Methane] has 28 times the warming potential of carbon dioxide, but with a shorter lifespan. If we can reduce methane emissions now, we could slow down [their warming potential] in 10 years’ time. Reducing carbon? That effect is 100 years later.”
Credit: Adam Gibson
Dr Tatsumi is a guest speaker at the Beaker Street Retreat, a weekend science retreat that’s an offshoot of the Beaker Street Festival. With seminars about happiness, space and seaweed, it’s a bit like school camp for nerdy grown-ups, albeit with much nicer lodgings. (Guests stay at the luxurious Piermont Retreat in Swansea.)
About 30 of us are huddled in a portable building at Sea Forest’s Swansea outpost, where Dr Tatsumi monitors the asparagopsis. The site is a former abalone farm, chosen for its proximity to sea water. Dr Tatsumi’s “pom poms”, as the asparagopsis is affectionally known, are grown above ground here, in the raceway ponds, and underwater off the coast of Triabunna, where Sea Forest has a marine lease.
Dr Tatsumi began working with Sea Forest in 2019, when he was a research fellow at UTAS, then studying the ecological impacts of climate change, as well as the rehabilitation and conservation of marine environments. He’s been head of research at Sea Forest since 2021.
The Osaka-born scientist first came to Tasmania from Japan as a teenager in the ’90s to visit an uncle. “I didn’t speak any English at the time, and it was just me and my sister – no parents!” he says. “It was such a big adventure, and the nature really got me. I knew that I would have to come back again.” While attending an agricultural high school in Japan, Dr Tatsumi threw himself into the science, finally returning to Tasmania in the early 2000s. He would complete his PhD in 2019.
Beaker Street’s main ethos is “science for the people”, and it’s easy to see why Dr Tatsumi is involved in the program: he’s really good at explaining complex ideas to people who aren’t scientists.
“SeaFeed contains an active compound from the asparagopsis,” he says, holding up a vial of SeaFeed with canola oil that looks exactly like canola oil (even he can’t tell the difference, once it’s mixed in). “When the cattle consume it, it inhibits the process of bonding carbon and hydrogen, which is a byproduct of the fermentation that happens when cows eat. Normally, that byproduct bonds together to become methane, but the SeaFeed stops that.” Ergo, the cows burp out less methane.
“Does it work on humans?” one of my cohort asks. No, sadly. Just cows.
Being able to grow asparagopsis on land is a key part of the plan, Dr Tatsumi says, because that’s where the cows are. Farmers can add SeaFeed directly to the cow’s feed, or distribute it in salt-block form for grass-fed cattle.
Tasmania doesn’t have capacity to grow enough SeaFeed for the 1.5 billion cows on the planet, but Dr Tatsumi hopes to one day see seaweed farms all over the world.
“When we have a new idea for seaweed, we always think about energy intensity when we transfer [that idea] overseas,” Dr Tatsumi says. Tasmania has hydro power, but much of the world doesn’t – so the raceway tanks were designed to use as little energy as possible.
While SeaFeed is “a very small piece of a very large agricultural machine”, it has the capacity to make an enormous difference, Dr Tatsumi says.
“If we feed SeaFeed to all cattle in Australia," he says, "we could reduce 15 per cent of national greenhouse emissions.”
The key challenge is convincing people that lower-methane beef is worth paying for. Tasmanian dairy Ashgrove already uses SeaFeed for its Eco-Milk, which it calls “a world-first climate-friendly milk”. It costs around 10c more per litre than Ashgrove’s regular milk. In Sydney, restaurant Three Blue Ducks has partnered with Sea Forest for its “Sea Fed Beef”.
“What we need is more farms using SeaFeed, but also the consumer support for lower methane [beef], which may come at a cost," Dr Tatsumi says. "If the customer doesn’t want to pay, then is it the farmer who pays to help the environment? It’s a catch-22."