Restorative Seafood Aquaculture is the Future

by Erika Bolliger - in collaboration with Ocean Wise

THIS ESSAY WAS FIRST PUBLISHED IN PRINT IN DECEMBER 2020, IN ISSUE TWO

Imagine a farm where farmers drive boats instead of tractors, create habitat rather than destroy it, and the farm itself actively cleans waterways and combats global warming.

Imagine farm animals that don’t need to be fed, yet provide affordable, high-quality protein. This dream is a reality, and it’s called restorative aquaculture.

Today, more people are asking about where their food comes from: who grew it, how far it travelled, is it environmentally-friendly? Some of the answers are as simple as reading a “Grown in Ontario” food label. For seafood, however, these questions are more complicated to answer.

Seafood encompasses over 700 varieties of regularly consumed finfish species and a diversity of shellfish including mussels, oysters, crabs, and shrimp. Cephalopods like squid and octopus, or more uncommon menu items like sea urchins, abalone, and seaweed all fall under the umbrella of seafood. This incredible variety is part of the appeal, but with this variation comes equally complex food systems. Depending on the species, location, and method of harvest, eating seafood can significantly impact the long-term health of wild populations and their habitats.

The Ocean Wise Seafood program is a non-profit conservation organization that works to simplify seafood by researching and recommending sustainable sources. The Ocean Wise symbol on a menu or packaging then gives you the power to make an informed decision about the food system you want to support. The goal of the program is to protect oceans, lakes, rivers, and aquatic life by supporting access to responsibly-sourced seafood.

Seafood is the main source of protein for over 1 billion people worldwide and satisfying that demand unsustainably can have a terrible price. According to the Food and Agriculture Organization of the United Nations (FAO), over one third of fish stocks (the discrete populations of harvested fish species) are overfished. Additionally, roughly 40 percent of what is caught by commercial fishing vessels is bycatch (the unintentional catches of non-target species), which includes: turtles, dolphins, sharks, and more. Fishing gear, such as giant trawling nets, can also be responsible for habitat damage by tearing through kelp forests or coral reefs.

Fishing can be done sustainably when there is a good management plan in place, the stock population is healthy, and the fishing method has little to no impact on habitats or other species.

Fishing is not the only way we get seafood, according to the FAO, more than half of the seafood that we eat today is farmed. Seafood farming, or “aquaculture”, earned a bad reputation in the 1980s and ‘90s due to poor salmon farming practices and the ongoing destruction of mangroves for shrimp farms. Detrimental aquaculture has caused significant environmental damage, but just as in wild capture fisheries, there are sustainable and unsustainable farming methods.

Restorative aquaculture is the cultivation of low trophic level restorative species, such as seaweed and bivalve shellfish (e.g. mussels, clams, and oysters), to positively affect ecosystem services. Ecosystem services are the beneficial outcomes of healthy ecosystems, such as improving air or water quality, supporting biodiversity or providing food.

Restorative species are low on the food chain as primary producers, such as plants or algae that convert energy into food, or filter feeders: the bivalve shellfish that survive by consuming nutrients and organic matter floating in the water. Restorative aquaculture systems have the potential to improve the environment, provide long-term job security for fishers, and support healthy consumer diets.

Unlike land-based farms that require large amounts of fertilizers, land and freshwater, seaweed and shellfish require no inputs to grow. Instead, they survive off nutrients and food naturally found in the water. For this reason, bivalve shellfish are a particularly sustainable protein source, no other animals or plants need to be grown and harvested to feed shellfish. Zero input protein is critically important to support healthy diets and a clean future.

According to The Nature Conservancy, growing seaweed and bivalves together is mutually beneficial; the bivalves improve water clarity by absorbing excess nitrogen and phosphorus, which allows more sunlight to reach the seaweed. In return, seaweed oxygenates the waterways. Kelp forests also act as carbon sinks for atmospheric carbon dioxide, absorbing 200 times more carbon than the ocean, thus helping mitigate climate change. Seaweed and bivalve aquaculture also increase local biodiversity by providing habitat structure and refuge for fish, crustaceans, and other invertebrates.

Eating seaweed is good for the environment, and for you. Alex Mifflin of The Water Brothers notes, in a blog post for Ocean Wise, that seaweed species can contain more vitamin C than citrus fruits, more vitamin D than milk, more iron than red meat and more protein than eggs and soybeans. Seaweed is also high in iodine, which boosts thyroid function and metabolism. Seaweed is so sustainable that all species of seaweed cultivated anywhere in the world are Ocean Wise recommended.

It is a commonly held assumption that sustainable seafood is more expensive for the consumer. While this can be true in instances of premium fish or crustaceans, restorative species like mussels and clams are particularly affordable sources of high-quality protein. Mussels also offer a well-rounded source of zinc, iron, vitamins A, C and B12.

Choosing restorative species like seaweed and bivalve shellfish is an effective way to contribute to personal and environmental health, but it is important to check that they are sustainably sourced. Some are overharvested or are harvested using damaging gear types. For example, dredges are metal baskets with large teeth that drag across the ocean floor to lift buried clams or shellfish, which can result in bycatch and significant habitat damage if done in sensitive areas. Look for the Ocean Wise symbol or use the Ocean Wise Seafood Search engine to check whether the species you want to eat is recommended.

By choosing restorative species or Ocean Wise recommended seafood, you create demand for ethically-sourced options and withdraw support from damaging industries. There is incredible potential for restorative aquaculture to promote food sovereignty, and it starts when you make a sustainable choice.

For more information about the Ocean Wise Seafood program, please visit ocean.org/seafood.