Ocean Farming

(by Maya Pelletier)

Imagine this: it’s 2050, you live in a small coastal city, and you’re sitting down to dinner with a couple of friends. The meal is veggie burgers made out of… seaweed? Yes, that’s right: seaweed. The seaweed (also called ‘kelp’) was grown nearby on an ocean farm owned by a cousin of your friend, their 11-year-old son tells you proudly. He recently visited a similar farm on a school field trip and has talked about nothing else since: the boat, the ocean, the dock, the oysters, the kelp – even the environmental benefits from the farm which he precociously calls “ecosystem services.” He tells you that when he grows up, he wants to have a kelp farm of his own: “Ariel from school said she wants to have an oyster farm, so we’ll both have farms right next to each other. We’ll get to be captains of our boat AND we’ll be rich,” he brags. “Well, maybe not rich, but it will be a good job,” his parents correct him. “And you’ll be helping the environment,” they add as you all sit down to enjoy the healthy, local meal. 

Credit: image courtesy of Atlantic Sea Farms

In this possible future, ocean farming, also known as aquaculture, has grown substantially around the world so that a quarter of the protein we eat comes from the sea – a number that is even higher in coastal communities that source their food locally. Choosing fish, shellfish and seaweed proteins that contain less saturated fat while providing other key nutrients such as amino-acids, vitamins, and minerals is improving people’s health across the board. With the adoption of marine polyculture (farming of multiple organisms with complementary roles in their environments), ecosystem health is up, too. Shellfish and seaweed farms are helping filter waterways that had been polluted with nutrients, and seaweed farms provide a buffer for storm surges from the increasingly intense storms brought by climate change. Most importantly for the climate, ocean farming has alleviated some of the pressure to use more and more land for agriculture by providing an alternate food source. With careful planning, the aquaculture industry is moving in a different direction from land-based agriculture: more biodiversity, smaller farms, more consideration for local ecology, less pollution, and shorter supply chains. 

To reach a future where aquaculture is practiced widely enough to make a dent in the climate crisis, we need people to step into a host of different careers. Most obviously, we need ocean farmers. But we also need research scientists, product developers, professional chefs, policy makers, marine spatial planners, engineers, boat captains and others, all devoted to strategically implementing sustainable aquaculture at a scale where it can help.

The problems aquaculture helps solve

In our page on Agriculture, Forestry and Other Land Use, we explain that humans use about half of all the habitable land on earth for agriculture – a fraction that is expanding every year, as the human population climbs from 8 billion today toward a projected peak around 10.4 billion later this century. When we cut down forests and plow savannahs, wetlands, and other wildlands under to make room for agriculture, we release the carbon stored in these rich carbon sinks into the atmosphere – and we crowd out other plant and animal species, by destroying the habitats and ecosystems they depend on. Nutrient runoff from agricultural fertilizer pollutes our waterways and produces large “dead zones” in our oceans through eutrophication. We cannot solve the unholy trifecta of the climate crisis, the biodiversity crisis, or the eutrophication crisis without finding ways to feed more people while using less land and less fertilizer. 

Enter: the ocean. It’s big, it’s blue, and currently we only source 2% of the world’s food from its salty depths despite its covering 70% of Earth’s surface. This is not surprising: humans live on land; we know how to farm on land; and we have a long history of domesticating and cultivating terrestrial plants and animals. The ocean, on the other hand, is not a “domestic” place. It is a frontier shrouded in mystery, with tales of pirates, deep sea monsters, lost cities and civilizations of creatures never seen by human eyes. Although coastal communities across the globe have long histories of relying on the oceans for food, ocean farming only began to emerge at a meaningful scale in the 1960’s; and it wasn’t until 2013 that fish farming overtook wild fisheries. Even now, with aquaculture surpassing wild fisheries by over 10 million tons, we are still only getting a tiny fraction of our calories from aquatic environments.

By expanding existing ocean farming practices and developing technologies that will allow us to farm in new parts of the ocean further from shore, we can help to reduce agriculture’s pressure on the land – and also the need for inputs to farming like synthetic fertilizer. What is more, instead of harming natural systems, as much land-based agriculture does, aquaculture can itself offer many ecosystem services that benefit natural systems when it is developed with surrounding natural, social, and cultural environments in mind. Shellfish such as oysters, mussels and scallops are filter feeders, so shellfish farms can clean up some of the excess nutrients that reach the ocean as fertilizer runoff from land-based agriculture. Seaweed farms also take excess nutrients from the water while simultaneously helping to fight ocean acidification on a local scale by absorbing carbon dioxide from the water around them. What is more, kelp and mussel farms can function as artificial reefs, providing important habits for fish and crustaceans. In addition to providing these ecosystems services while producing food and relieving agricultural pressure on land, ocean farming can create good jobs for people who want to work on the water. This can be a lifeline for coastal communities whose economies and identities have been based on fishing, but where fisheries are now declining due to climate change.

Credit: Marine Scotland

Careers in Ocean Farming

In parts of East and Southeast Asia, seaweed farming and marine polyculture are well established industries – though they are sites of ongoing innovation. In most other parts of the world, they are still baby industries, just taking their first steps. In order to get these novel industries on their feet and help them grow global aquaculture to a scale where they can make a real difference, a lot needs to happen. We need more farmers, of course, and we also need researchers figuring out how to design farms suitable for a variety of existing ecosystems. And we need engineers to figure out how to make farming work in the open ocean. We also need to increase demand for kelp and other foods that marine polyculture can produce. That means inventing new products and marketing appealing ways to use them, from seaweed burgers to cookies made with kelp flour to alternative plastics made out of, you guessed it: kelp! And finally, it means developing infrastructure like processing plants that are needed to turn farmers’ fresh harvest into sellable goods. 

Here we will consider a few different career pathways for working in aquaculture: (1) farming and farm support, (2) food processing and product development, (3) research, (4) policy, and (5) education/workforce development.

Farming and farm support

The farmer

You can’t have an aquafarm without a farmer! People who own or work on aquaculture farms need to learn skills in crop husbandry; they aren’t afraid to get their hands dirty repairing equipment, and they often have a knack for practical problem-solving and working with their hands. They get the satisfaction of seeing their crop grow from seed to harvest, and they get to spend their time out on the water, a definite perk.

The engineer

If your jam is devising new ways to farm that are better for farmers and for the environment, engineering may be right for you. These folks usually start by looking at existing farm infrastructure and figuring out how systems work together physically before tinkering with the numbers to see how they could be improved. They drive innovation that makes ocean farming more productive, economical, and practical for farmers.

The mechanic

An honorable practical genius who solves problems with their hands, the mechanic keeps everything running. From repairing boats, to fixing farm equipment, to occasionally inventing new “fix-it” tools for farmers, the work these folks do keeps the working waterfront afloat. Often enough they are also farmers or engineers themselves, as these roles aren’t mutually exclusive.

Food processing and product development

The chef

Aquaculture needs chefs! These brilliant people take new ingredients that no one knows what to do with, and turn them into delicious food. Chefs may work in restaurants or they may work in seafood companies, where they invent new products to test in the market. Wherever they work, they chart new paths from aquaculture to our table – and our stomachs! 

The marketer

 Even when a chef invents a delicious new food, it will sit on a shelf untasted unless someone crafts a story and images around it that make people want to try it. That’s where the marketers take action. They are often people with contagious enthusiasm for the products they are selling, and think in many different mediums, from taste to imagery and language.

The processor

Processors are essential intermediaries between farmers and our plates. They build businesses turning raw seaweed and other seafood into things that can be sold in grocery stores and restaurants – and often do the logistical work of delivering where it needs to go. They frequently operate behind the scenes, but you cannot have a successful farmed seafood industry without them.

Research

The biologist

Working and thinking at scales from DNA to the whole biosphere, research biologists are crucial to making sustainable aquaculture possible, and making sure that it helps the environment in which it is located rather than harming it. Biologists do work from breeding new species with farmers to creating regulations with policy makers so that ocean farms are sustainable.

The food safety scientist

Novel foods can affect human health through unexpected chemical and biological pathways. This matters for the growth of ocean farming not only because aquaculture opens up whole new domains of ingredients, but also because, if it scales enough to make a difference to climate, many of us will eat existing ingredients in much greater quantities than we do now. Chefs and processors might team up to make the most delicious food on the planet, but it cannot reach our tables until food safety scientists have carefully studied its interactions with the human body. 

The social scientist

 As we expand aquaculture, it will affect waters and coastlines that are already used for fishing, lobstering, and tourism – and it will change the coastal communities built around these. In order for aquaculture to be a climate solution, communities will need to support these changes and incorporate aquaculture into their sea-scapes. This has begun to happen in some locations, while in others proposals to grant permits for ocean farming have been met with skepticism or outright rejection. Social scientists work to understand how ocean farming is integrated into the public consciousness, and what needs to happen for it to be embraced.

Policy

The planner

To translate a bold vision in which aquaculture feeds millions into reality, we need people to hash out the details and help the whole industry – farmers, processors, policy-makers – work together, so that their actions build upon each other rather than pulling in different directions.

The policy-maker

The ocean is not the ‘Wild West;’ it is governed by overlapping frameworks of local, state, and national laws – most of which were never devised with ocean farming in mind. We need policy-makers who make sure that laws and regulations governing the ocean are based on science and community needs, and that they serve the public good.

The regulator

Oceans aren’t like land. As we are frequently reminded by storms, tides, and currents in motion around us, you can’t own the ocean. It is a shared resource. It is the task of regulators to enforce the rules ensuring that everyone treats this common good with respect and care.

Education and workforce development

The journalist

If aquaculture is going to take the world by storm, people need to understand it. Journalists can tell the story of ocean farming in all its many dimensions, from its effects on the climate to what it means for coastal communities, so that politicians making policy, restaurateurs designing menus, and individuals buying dinner will want it to succeed.

The educator

To build a generation of aquaculturists, we need to inspire young people to see themselves in aquaculture fields. To create these opportunities, we need educators in K-12 settings, universities, community colleges, and vocational schools to teach the many skills required by the array of careers we’ve discussed.

Is ocean farming sustainable?

When you hear the term “aquaculture” today, what do you think of? Depending on your experience, anything from large salmon pens to small oyster farms to ponds full of brightly colored carp might come to mind. You might think of aquaculture as a dangerous, polluting industry that could ruin ocean ecosystems – or as a solution to the problem of protein production for a global population with expanding calorie needs. Or maybe you’ve never heard the term at all.

The reason that you might think of so many different things is that aquaculture is an extremely broad term. It refers to the cultivation of any organism (plant, animal, or algae) in any aquatic environment (marine or freshwater). The term is not specific to scale, technological intensity, or global region. That means that the term encompasses everything from farming seaweed offshore, to low-intensity techniques for growing oysters on the bottom of an estuary, to cultivating finfish using technologically intensive, land-based Recirculating Aquaculture Systems like the one used by Bluehouse Salmon.


Just as a subsistence garden and a 725 acre cornfield fit into natural and human environments in very different ways with very different impacts, aquatic farms can fit into their ecosystems in many ways, positive and negative. Fish pens require inputs of feed (and sometimes antibiotics) and are known for the excess nutrients that they produce as effluent (a fancy word for fish poop). Seaweed farms, on the other hand, remove excess nutrients, along with CO2 from the surrounding water; and shellfish farms filter and clean the water column. Polyculture farms – for instance, when kelp, mussels and scallops are grown together – create complex farm ecosystems, which provide habitats in which fish and invertebrates can find refuge, forage, and spawn.

Credit: This is a still from a video by The Water Brothers.

Farms that not only combat pollution but also support broader, biodiverse communities of ocean life are more than sustainable: they can be regenerative. The Billion Oyster Project is an example of aquaculture that is actively rebuilding ecosystems that human activity destroyed.

So, let’s bust the myth that aquaculture has to be a polluting industry that will destroy our oceans. We can farm the ocean in ways that reproduce the environmental harms caused by land-based, extractive monoculture farming – or we can farm the ocean in ways that are sustainable and even regenerative. Because the aquaculture industry is still largely in its infancy, we have the opportunity to shape it intentionally and adaptively – that is, based on our current best understanding of the way ecological, social, and economic systems work, and responding in real time to problems as they arise. For this to happen, we need a whole generation of thoughtful, idealistic people who are not afraid to venture into new realms and build new systems to grow food for people and the planet.

Resources

  • Bren Smith is an influential early innovator in North American kelp farming. His book, Eat Like a Fish tells the story of his own journey from ocean fisherman to coastal kelp farming, and lays out a compelling vision of ocean farming as a climate solution.

  • You can also listen to this two-part podcast interview with Smith.