Science·What on Earth?

'Regenerative ocean farming' could be coming soon to a coast near you

In this week's issue of our environment newsletter, we look at the concept of 'regenerative ocean farming' and a Siberian oil spill with larger ramifications for the world.

Also: Siberian oil spill sounds climate change alarm

(Sködt McNalty/CBC)

Hello, Earthlings! This is our weekly newsletter on all things environmental, where we highlight trends and solutions that are moving us to a more sustainable world. (Sign up here to get it in your inbox every Thursday.)

This week:

  • 'Regenerative ocean farming' could be coming soon to a coast near you
  • A Siberian oil spill shows how climate change is affecting infrastructure
  • A B.C. research lab is trying to design a more sustainable face mask

'Regenerative ocean farming' could be coming soon to a coast near you


Monday was World Oceans Day, which got a lot of us thinking about problems like overfishing, plastic pollution and rising sea levels as a result of climate change.

But Bren Smith, the Newfoundland-born owner of Thimble Island Ocean Farm off the coast of Connecticut, wants to change that view.

"Those of us on the ocean want to ... embrace the ocean and figure out how to see it as a place for climate solutions," Smith said during a recent interview from his boat off Long Island Sound, where he was harvesting kelp.

Smith is the pioneer behind "regenerative ocean farming." It involves growing seaweed and several kinds of shellfish — not just to feed people but to heal the oceans and fight climate change. He said the aim is "going beyond sustainability and using our crops to breathe life back into ecosystems."

For example, kelp soaks up carbon as it grows, helping to mitigate climate change, Smith said. Growing seaweed is the ocean equivalent of "afforestation" — planting trees where there weren't any before. It similarly helps provide habitat for other organisms, in this case by creating an "artificial reef" to rebuild local underwater ecosystems. Meanwhile, oysters, clams and mussels — native species that get all their food from the local environment — filter and clean the water.

To capture this bounty, Smith uses ropes that run between floats on the surface and the ocean floor over 16 hectares off Long Island Sound.

After harvest, the shellfish go to stores and restaurants to be eaten, while different parts of the kelp are used to produce: 

  • Human food, including pickles and chutneys.
  • Fertilizer and compost for land-based farms.
  • Compostable bioplastic.

Smith is a former fisherman who worked at salmon farms on Canada's East Coast and became concerned about the environmental impact of both fishing and aquaculture. He tried growing oysters on the East Coast of the U.S. but decided he needed to do things differently after his oyster stocks were destroyed by back-to-back hurricanes (Irene and Sandy) in 2011 and 2012. 

Initially, he expanded to other kinds of shellfish. Then, working with University of Connecticut marine scientist Charles Yarish, he began adding "vegetables."

"That was great, because the kelp is a winter crop," he said, meaning he can count on kelp during times of the year when he can't harvest shellfish.

Smith, who was named one of the 25 people "shaping the future" (alongside the likes of Elon Musk) by Rolling Stone in 2017, has started a non-profit called GreenWave to help others start similar farms. Some are already running on the east and west coasts of the U.S., and he's working with First Nations communities on Vancouver Island and Newfoundland to get equipment in the water this winter.

He's also hoping to expand to more crops and markets. He thinks the ropes and floats make great platforms for environmental sensors to track the impacts of climate change and water acidification, and hopes farmers will be able to sell that data. Next year, he's hoping to launch the sale of carbon and nitrogen offsets, allowing people and companies to pay to "cancel out" some of their own emissions.

Smith said the benefits of regenerative ocean farming aren't just environmental. The startup costs are low, since ropes are the main equipment and you don't need to own any land. Meanwhile, having a diverse set of crops with multiple markets reduces economic risks — for example, while COVID-19 has shut down many restaurants, the main market for oysters, clams and kelp are still selling. 

There are other challenges. The biggest ones, Smith said, involve "land-based" issues after harvest, such as processing, which can be very expensive. Even so, he is hopeful that the expansion of this type of farming could help generate jobs and profits from climate change mitigation.

"The opportunity here is that we can put people to work helping solve one of the biggest crises of our times, which is the climate crisis. Let's repurpose people like me, turn them into an army of climate farmers."

Emily Chung

Reader feedback

After we highlighted the first flight of an all-electric Cessna Caravan in Washington state a couple of weeks ago, several readers wrote in to say that a similar milestone was reached in December 2019 by a Harbour Air seaplane in B.C. If you'd like to read more about it, we reported on it in our Dec. 12 issue.

Write us at

Old issues of What on Earth? are right here.

The Big Picture: Siberian oil spill

Oil spills have become an all-too-common occurrence. A recent accident in Siberia speaks not only to the immediate environmental cost of such accidents but also the role of climate change in making them more likely. On May 29, a failure in a storage tank at a power plant sent more than 18,000 tonnes of diesel fuel into a river near the town of Norilsk, Russia, and it is feared this toxic load will eventually make its way to the Arctic Ocean. The spill has infuriated Russian President Vladimir Putin, and the plant's director has been taken into custody. According to Russian news agency TASS, the plant operator's parent company, Nornickel, said the ultimate cause of the spill may have been a sinking foundation on the storage tank. And that, in turn, may be the result of thawing permafrost in the region, which has been gradually warming.

(Irina Yarinskaya/AFP via Getty Images)

Hot and bothered: Provocative ideas from around the web

A B.C. research lab is trying to design a more sustainable face mask

(Dillon Hodgin/CBC)

The increased use of personal protective equipment (PPE), such as face masks and rubber gloves, is helping us to collectively ward off the novel coronavirus. But it's also creating a litter problem. 

People who oversee sewer and solid waste systems are reporting a rise in the improper disposal of PPE, which can clog pipes.

"Whether they're wipes, whether they're masks, whether they're rubber gloves, all of those things can't be treated in the sewage system and, in fact, damage our equipment," said Jerry Dobrovolny, chief administrative officer for Metro Vancouver.

PPE is also being discarded on the street, and can be flushed into storm drains, many of which empty straight into streams or the ocean. Richard Thompson, a professor of marine biology at the University of Plymouth in the United Kingdom, notes that this new waste stream is adding to the already serious problem of microplastics, the tiny pieces of debris now found in every ocean.

"The sea is sort of downhill from everywhere, and so there's a tendency for materials to accumulate there carried by rivers or carried by wind."

Thompson said society needs to understand and deal with what happens to all disposable items after they're used. "The persistence of litter is incredibly long-lasting — hundreds if not thousands of years — and that's why it's really important that that end-of-life phase is fully thought out."

Disposable masks, for instance, may feel like soft cotton, but they're almost all made from non-biodegradable material such as polypropylene.

At a research lab at the University of British Columbia, a group of scientists saw the problem and decided they could put a dent in the growing waste pile. They recently formed an ad hoc team to come up with a less-damaging face mask.

"This is all paper — all wood fibre," said Orlando Rojas, a professor at UBC's Bioproducts Institute (see photo above), pointing to an array of materials and mask prototypes on a workbench.

Canada has a long history of making paper products, and Rojas is confident once the right formula is found, millions of eco-friendly masks and other protective gear can be produced at low cost.

The key is creating a soft, durable paper product that can still filter out viruses. Rojas said many of the initial technical hurdles have already been solved, and talks are underway with manufacturers.

A made-in Canada-solution, with the potential for local manufacturing, would also help ensure the country isn't caught short again when it comes to supplies of crucial equipment needed to fight the pandemic, said Rojas.

It could be a long-term proposition, with people all around the world now wearing face masks and concern growing over their impact on the environment.

"People are very conscious about sustainability, so this flies really high in people's minds. If we match that interest with the performance of wood fibre, we likely have a winner here," Rojas said.

Greg Rasmussen

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Editor: Andre Mayer | Logo design: Sködt McNalty

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