In Alaska and British Columbia, Seaweed Farming Holds Promise for People and Nature

A new industry emerging across coastal communities in Alaska and British Columbia could—if managed responsibly—be a big win for people and nature. At a time when local ecosystems and economies in these regions are under stress from a myriad of factors, including warming waters and declining fisheries, seaweed farming is a bright spot on an otherwise uncertain horizon. That’s why The Pew Charitable Trusts has launched a new effort to work with local organizations, Indigenous groups, scientists, and policymakers in Alaska and British Columbia to help build the foundation for a sustainable seaweed farming sector that represents the interests of coastal communities, while protecting the ocean environment they rely on.

The cultivation of seaweed along coastal areas has the potential to produce numerous ecological benefits, from reducing local ocean acidification and improving water quality to providing habitat for coastal and marine wildlife. At the same time, farmed seaweed can generate revenue as a carbon-friendly product. Seaweed is sold alone as food—as it has been for years—and is also increasingly used in a range of other products, including pharmaceuticals, fertilizers, packaging materials, and nutritional supplements. Today, the global seaweed market has an estimated value of $11 billion to $13 billion and is projected to grow substantially over the next five years.

Of course, as with most emerging sectors, a dose of caution should temper the excitement. If businesses and governments mismanage the expansion of seaweed farms, the industry could threaten coastal ecosystems, damage ocean habitat, and exclude the small farmers and Indigenous communities that have the most to gain—and lose—from seaweed farming. To help guard against those outcomes, government agencies in Alaska and British Columbia will need to put in place appropriate guardrails to minimize any negative effects from the industry as it scales up while also ensuring that local communities, including Indigenous peoples, help shape its growth.

Past lessons can help

According to the Food and Agriculture Organization of the United Nations, global aquaculture production—which includes algae, salmon, shrimp, and more—reached a record 130 million metric tons in 2022, with farmed seaweed accounting for nearly 30% of that.

Today, nearly 95% of that seaweed production takes place in Asia, due in part to a decades-long push in China to position seaweed as a food product and to harness its ecological benefits to filter excess nutrients from heavily polluted coastal waters.

And although China achieved those two goals, its coastal regions have also suffered ecological damage. For example, in some places, concentrated seaweed farms blocked too much light from penetrating through the water column, which changed marine life behavior and threw the food web out of balance.

First Nations in Canada and Tribes in Alaska have already experienced how short-sighted resource management can harm the environment. For example, although mining, logging, and fishing are financially important sectors in the region, they have, in some cases, led to significant pollution, deforestation, and overfishing, hurting the wider ecosystems. Poorly managed seaweed farming can also negatively affect people and their communities. For instance, without proper safeguards, a few large companies could secure the most valuable farming permits and licenses, essentially shutting locals out of the industry.

Seaweed farm design should include community input

Fortunately, there are proven methods for developing this sector in a sustainable way. This includes adoption of sufficient ecological safeguards, such as requirements to farm only native species, to minimize the sector’s negative effects on the surrounding ecosystem; implementation of cost–effective ecological monitoring approaches to assess farming impacts as the industry scales up; and ensuring that Indigenous farmers and other small-scale operators are actively engaged in creating a vision for seaweed farming in their communities—and are positioned to benefit from the industry’s development.

Many decision-makers at the federal, state, and provincial levels as well as Indigenous communities, nonprofit organizations, and foundations are already working to help advance some of these approaches. As we launch our new effort, Pew will be supporting Indigenous communities and working alongside partners to help advance seaweed farming in a way that builds ecosystem and community resilience, and helps the people and nature of the British Columbian and Alaskan coastal areas thrive far into the future.

Jamie Gibbon is a senior officer with The Pew Charitable Trusts’ seaweed farming project and Rebecca Harris is an associate working on Pew’s conservation support team.