GreenWave’s Regenerative Ocean Farming: A Case Study in Generating Ecosystem Services
Currently about 40% of the world’s population resides within 100 kilometers from the coast, many of which depend on ocean resources to make a living, through subsistence, tourism, recreation, and […]
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Currently about 40% of the world’s population resides within 100 kilometers from the coast, many of which depend on ocean resources to make a living, through subsistence, tourism, recreation, and other economic activities.  In 2010, 39% (123.3 million) of US citizens lived in counties directly on shorelines, with an expected 8% (10 million) increase by 2020.  It is estimated that around 60 million people are employed by the fishing and fish-farming industries. In 2016, these industries harvested around 171 million tons of fish, valued at US$362 billion. In addition to employment opportunities, fish and other marine resources are important parts of the human diet, providing animal protein to much of the world.

As coastal populations increase, along with the growing taste for specific seafood, so do threats to ocean ecosystems and their marine resources. Marine plastics and other pollution, toxins, disease, coral reef bleaching, agricultural run-off, land development, and overfishing are all factors putting our oceans at risk of destruction, as evidenced by tremendous dead zones and declining species counts.  

Hypoxic zones, also known as “dead zones,” refer to areas of where there is less oxygen dissolved in the water, causing most marine life to die or leave the area, transforming once thriving areas into “biological deserts.”  While some dead zones occur naturally, human-caused nutrient pollution (from agricultural runoff land for example) and wastewater discharge are major causes, stimulating “an overgrowth of algae, which then sinks and decomposes in the water.”  Decomposition consumes oxygen, leaving little for marine life. In the US, dead zones are found along the East Coast and the Great Lakes,” with the world’s second-largest dead zone in the northern Gulf of Mexico.

In order to stop the decline of our world’s oceans and build more resilient communities and industries, new concepts and initiatives are forming to address some of the immense challenges. The “Blue Economy” approach “supports economic growth, social inclusion, and the preservation or improvement of livelihoods while at the same time ensuring the environmental sustainability of oceans and coastal areas.” 

Following this approach, former fishers and ocean workers like Bren Smith, ocean farmer and founder of the non-profit GreenWave, have created a new framework to help combat the decline of the world’s oceans while creating a more just and equitable transition from traditional commercial fishing to what they are calling regenerative ocean farming. In practice, this involves developing “small-scale farms where complementary species are cultivated to provide food and biofuel, clean up the environment, and reverse climate change,” according to Project Drawdown.  Regenerative ocean farming, as implemented by Thimble Island Ocean Farm, holds promise as a sustainable form of food production, with many social, economic, and environmental benefits.

A “GreenWave” in the Blue Economy: A Case Study in Regenerative Ocean Farming

Based on the success of his own ocean farm, Bren Smith, the owner and operator of Thimble Island Ocean Farm (TIOC), founded GreenWave, a non-profit “dedicated to training and supporting regenerative ocean farmers in the era of climate change… to create a blue-green economy—built and led by regenerative ocean farmers—that ensures that we can all make a living on a living planet.” The organization’s mission is “to restore marine ecosystems by creating 3D ocean farms that provide habitats for thousands of fish, filter the water of deadly carbon and nitrogen, and grow tons of sustainable shellfish and sea plants.” Using TIOC as a model, GreenWave is accomplishing these goals through farmer training, resources, and support, in addition to value-added research, infrastructure development, and hatchery services. They also are helping to build markets through a Buyers Network, bringing together “regenerative ocean farmers and buyers across diverse industries in mutually beneficial relationships that support thriving farms, coastal communities, and marine ecosystems.”

Functionally, the farm is essentially “an underwater garden” says Smith, “one with hurricane proof anchors on the edges.” About eight feet below the surface, the garden begins. The kelp and other seaweeds grow on vertical columns, followed by shellfish like scallops and mussels. At the bottom of the garden are  cages of oysters and clams on the ocean floor, hanging and attached to horizontal ropes.  Furthermore, regenerative ocean farming means “growing seaweed and shellfish (oysters, mussels, clams) in many small coastal underwater gardens of a few acres each, not constructing more industrial salmon farms.” In addition, “seaweeds and shellfish don’t need to be fed; they grow with just sunlight and the nutrients and plankton already in seawater.” 

GreenWave & Thimble Island Ocean Farm: Agroecological Roots

 Agroecology, as defined by United Nations Food and Agriculture Organization, integrates both ecological and social concepts and principles into applied and responsive “design and management of food and agricultural systems” and seeks “to optimize the interactions between plants, animals, humans and the environment while taking into consideration the social aspects that need to be addressed for a sustainable and fair food system.”  Assessment of an initiative’s effectiveness in achieving these goals provides tangible “global and harmonized” evidence for supporting agroecological transition and policy in order to build a knowledge base by empowering producers and identify global trends for replication and modification.

Thimble Island Ocean Farm ranks high in most areas of agroecological considerations, indicating the tremendous potential these farms hold in transitioning towards an equitable and sustainable food system. In terms of product diversity, TIOF grows multiple shellfish and seaweed varieties for both direct consumption and value-added products like kelp noodles and seaweed fertilizer for land-based crops. Diversified activities include conducting farmer training programs, ecotourism farm tours, and wind power harvesting.  The farm also facilitates shared processing infrastructure and operates the largest seed hatchery network in the world, which is a non-profit.  By producing some of their own shellfish and kelp seed, they are able to provide trainees with free seed, as “seed is the most expensive input for farmers,” says Smith. 

Regenerative ocean farming requires very little fossil fuel input (transportation, for example). Kelp soaks up five times more carbon than land-based plants, essentially offsetting this fuel input.  From a social standpoint, GreenWave and TIOF believe that this method of food production is truly regenerative, it must be inclusive of all.  The motto “who farms matters” is fully embraced by Bren Smith at his farm and non-profit, which supports the training and employment of First Nation peoples, people of color, immigrants, ex-felons, and other marginalized groups. The entire model is built around a “just transition” model, promoting social equity, living wages, and open employment.  By building a ladder towards economic justice, TIOF also ensures climate and social justice: “Climate solutions need to protect both people and the planet… inequality and social justice are central, not side issues… farmers deserve a more equitable slice of the economic pie,” states Bren Smith.

Ecosystem Services: Potential Economic, Social, and Environmental Impacts

An ecosystem is defined, by FAO, as the “living elements which interact with each other and their non-living environments [and] provide benefits, or services, to the world.” These benefits, known as ecosystem services, “make human life possible by, for example, providing nutritious food and clean water, regulating disease and climate, supporting the pollination of crops and soil formation, and providing recreational, cultural and spiritual benefits.” Ecosystem functions and services depend on biodiversity, or “the diversity among living organisms.”  Bren Smith explains the intentions of regenerative farming: “Our 3D farms are designed to address three major challenges: first, to bring to the table a delicious new seafood plate in this era of overfishing and food insecurity; second, to transform fishermen into restorative ocean farmers; and third, to build the foundation for a new blue-green economy that doesn’t recreate the injustices of the old industrial economy.” Given the biodiversity and its associated services supported by this method, regenerative ocean farming holds much potential for improving both the environment and human lives.

Benefits and Challenges

Regenerative ocean farming focuses on biodiversity, with multiple varieties of seaweeds and shellfish.  “With over 10,000 edible plants in the ocean, we’ve barely scratched the surface,” says Smith.  Seaweeds contain vital nutrients and vitamins like vitamin C, protein, and Omega-3s. In addition, pressure on fish stocks can be lessened by eating a variety of marine resources.  Seaweed also assists in carbon sequestering from both the ocean and atmosphere, while shellfish consume nitrogen and phosphorus-containing plankton and detritus, playing an integral role in nutrient cycling of coastal habitats.  These farms also provide habitat for wild ocean species.

Worldwide, 80% of fish stocks are “fully exploited or overexploited” with rampant Illegal, unregulated, and unreported fishing further stressing these resources. Around 97% of the world’s fishers reside in developing countries, with fishing as their major source of food and income. Women make up most of the workforce involved in secondary marine-related activities, like processing (United Nations, 2017). These declining fish populations pose a real threat to job security.  The vision of regenerative ocean farming provides fishers and processors with a transition to a more sustainable economy and food production system.

Bren Smith recognizes the need to create a better system for ensuring this work makes a meaningful impact. He identifies the necessary policy to ensure farming is accessible to all, including keeping leases affordable, limiting acreage to stave off monopolies, creating “sea trusts” to ensure stewardship, and requiring open employment with living wages. Despite the relatively low start-up costs, it remains to be seen if developing countries have access to technical training and financial resources to start regenerative ocean farms. There is also the possibility of corporations co-opting this movement, without fully embracing agroecological principles, as we have seen in other movements like certified organic. Currently, given the intensive processing required, many products containing seaweed and shellfish are too expensive in much of the world.  Without being accessible to all populations, this model will not be an impactful way to feed the world.

While there is great interest in ventures around seaweed, many potential regenerative ocean farmers have found it difficult to begin operations with the multiple challenges around processing requirements, testing, and lengthy waiting times for obtaining leases and permits, as experienced by some Alaskan ocean farmers.  In addition, some farmers have found that the hardships of growing and processing seaweed on a small scale outweigh the economic benefits currently being generated.  There also seems to be quite a bit of funding for research around ocean farming, but much less financial support going to actual farmers.  

Current Impacts of Regenerative Ocean Farming

Given that regenerative ocean farming is a fairly new concept, there is sparse data available. Production wise, one acre of vertical underwater gardens is able to grow between 10-30 tons of sea vegetables and 250,000 shellfish each year.  Relative to other marine and land-based food systems, start-up costs are minimal, with a low debt to income ratio. “Anybody with 20 acres and a boat and $30,000 can start their farm and be up and growing the first year. The key to replication is designing around simplicity, not complexity,” explains Bren Smith. In terms of income stability and resiliency, Bren Smith has shown that his farm is “able to net up to $200,000-$300,000 per farm and employ up to 10 people, and that’s just on the farm, that doesn’t count the processing centers.” Farm plans have remained open source and assessible to all. Smith offers direct support, shared knowledge bases, and training programs, helping to create local across various community demographics, including empowering a large percentage of women.

Between 1995 and 2016, worldwide production of farmed ocean plants grew from 13.5 million tons to just over 30 million tons.  In 2016, total global aquaculture production (including plants, shellfish and fish) was 110.2 million tons, with a value of around $243.5 billion. Given the industry’s growth, and its potential for environmental degradation, it is imperative that agroecological principles be applied to planning, development, and multi-sector impact measurement, like income, added value, and the empowerment of people.

Farms like Thimble Island Ocean Farm address global goals at a local level.  By providing training and inputs like seeds and farm plans, this model is helping to ensure and grow the sustainable productivity of seafoods and bioresources.  In addition, these farms can help reduce the reliance on harmful fish harvesting practices, like trawling, marine environments are nurtured and even improved through water filtration. From an environmental perspective, monitoring ecosystem services is vital. 

Carbon capturing, nutrient cycling, habitat creation, and storm surge protections are a few aspects researchers could measure. In addition, finding ways to measure the indirect productivity of other systems, supported by regenerative ocean farming, like increases in neighboring wild fish populations, would be valuable information in supporting this initiative.  Additionally, identifying the indirect productivity of other systems, supported by regenerative ocean farming, like increases in neighboring wild fish populations, would be valuable information in supporting this initiative.  Monitoring direct and indirect job employment and growth, as well as farm revenues and costs, will provide an overview of economic impact. 


In 1979, Jacques Cousteau foreshadowed the opportunities at hand today: “We must plant the sea…using the ocean as farmers instead of hunters. That is what civilization is all about — farming replacing hunting.”  To avoid pitfalls of industrialized agriculture – monocropping, the death of small family farms, high reliance on fossil fuels and inputs, and reliance on low waged workers– it’s imperative to build a system that protects the core visions and beliefs of this emerging industry.

Reforming systems around financing, workers’ rights, biodiversity protection, and the food system as a whole would be required to make ocean farming a viable option for all socio-economic statuses. Keeping equitable opportunity, place-based community input, and environmental health at the center of regenerative ocean farming is crucial to success.  Investing in product research and development and processing infrastructure are important components to building and expanding markets for affordable seaweed and shellfish products. Overall, regenerative ocean farming, as exemplified by Bren Smith, GreenWave, and Thimble Island Ocean Farm, appears to be a very sustainable model with the potential to alleviate stress on the world’s fish populations and land-based farms, while keeping environmental impacts to a minimum and supporting biodiversity.