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Seaweed as Savior

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The brown-green slimy ribbons on the beach, with the ocean smell, tangled up in boat motors and tickling the bottom of swimmers’ feet; it’s seaweed and it might just save us all. 

Across the world, seaweed production has been increasing by about 8% per year since 2014 with the industry currently valued at over $11 billion. In the US, it is on track for continued growth, with Maine and Alaska as the leading states. America’s seaweed industry is still minute however when compared with Asia–especially China, Indonesia, Korea, and Japan–where most seaweed aquaculture occurs

In February 2020, the World Aquaculture Society gathered on Oʻahu, hosting a special session entitled, “Seaweed aquaculture–from historic trends to current innovations.” The assembly covered topics ranging “from seaweed tank and pond cultivation, off-shore design and deployment, genetics and strain selection, algae education, uses and processing of algae for food, feed and biofuel, and the compounding challenges facing this developing industry,” according to the World Aquaculture Society’s website. 

And in coastal regions of America, judicial shifts are occurring, such as the “Kelp Bill” of New York, joining states like Connecticut, Massachusetts, Maine, and Rhode Island, and permitting for the first time the cultivation of kelp in Suffolk County. Critically, the bill, and others like it, marks real progress for cleaning up waterways and providing increased economic opportunity for local farmers. 

(A note here: Kelp is a type of seaweed, therefore all kelp is seaweed, but not all seaweed is kelp. The term “seaweed” encompasses over 10,000 species and is essentially an umbrella term for any marine algae that can be seen with the naked eye.)

Where seaweed is found, health abounds:
  • Seaweed is the fundamental piece of the ocean’s food web, acting as the base, much like grasses and plants act as the base of the food web for land-dwelling organisms. It is a habitat for small invertebrates and fish and is a primary producer of food for coastal regions’ native fish, crabs, urchins, and sea snails.
  • The photosynthesizing of algae contributes to 70% of all atmospheric oxygen. (Yes, you read that right.)
  • Coastal habitats and wetlands are estimated to absorb five times more carbon than terrestrial forests, according to scientists at the Red Sea Research Center of King Abdullah University of Science and Technology.
  • Bri Warner, president of Atlantic Sea Farms, the Maine company which became the nation’s first commercial seaweed farm in 2009 describes kelp as, “truly regenerative… a miracle crop in many ways. It doesn’t use fresh water. It doesn’t use land. It doesn’t need fertilizer.”
  • Seaweeds offer a promising source of sustainable and scalable bioenergy production. As it is composed of 85-90% water, it is suitable for biofuel-making methods such as fermentation to make ethanol.
  • Economically, seaweed farming offers coastal communities the opportunity to shift away from solely relying on offshore fisheries to a more sustainable and long-term alternative for revenue. With interest in edible seaweed production getting off to a strong start with no signs of slowing in the US, the potential is vast for those willing to invest in the industry now.
  • One of the most effective ways to be a sustainable consumer is to eat lower on the food chain. Seaweed is not only the base of the ocean’s food chain, but it also contains many antioxidants, a wide range of vitamins and minerals, is rich in fiber, and some varieties contain iodine, a trace mineral vital for thyroid function. Its benefits for human dietary health compliments its vast contribution to environmental health.

Yes, kelp absorbs carbon–a lot of carbon. But there is a catch. In the summer months, as temperatures rise, if kelp is not harvested, it dissolves and the carbon is re-released back into the ocean. The atmosphere only benefits if kelp is seasonally removed from waterways. 

For great swaths of the world, seaweed as food is nothing new. For other regions, where the idea of consuming seaweed is unfamiliar, and may even induce a cringe, there are emerging companies such as Akua launching kelp burgers, jerky, and pasta. Heavily beta-tested during the pandemic, Akua is projected to earn $1 million in sales this year

    All of this burgeoning in the economy of seaweed production leads to the question: Is kelp the new kale? It is more than possible. And perhaps it’s what we should all be rooting for because that slimy stuff has the makings to have a massively positive impact on our environment, much more so than kale could ever dream to. 

    Edible seaweed aquaculture can be a sustainable practice. To continue scaling, however, coastal regions will need to mimic the function of natural ecosystems, utilizing native species of seaweed for commercial production that will also show to be resilient under various climate change scenarios. This is ecological aquaculture, which not only mimics the form and function of natural ecosystems, but is also knowledge-based, and embedded in the larger context of social systems such as the human communities affected. 

Native Limu of Hawaiʻi:

In Hawaiʻi, native limu was assumed to be part of the landscape, ever-there, until it began to disappear. Limu is the ʻŌlelo Hawaiʻi word for edible plants living underwater, such as seaweed, or near the water, such as algae, and is a valuable resource with strong medicinal, cultural, and culinary importance across the islands. 

In the past four generations, children growing up in Hawaiʻi have gone from making plentiful limu “wigs” on the beach and gathering the abundance to eat at home alongside fish and poi, to most children never being exposed to native limu at the shore, or bestowed with knowledge about the importance of maintaining this resource. The steep decline or in some cases eradication of Hawaiʻi’s native limu species is in part due to the loss of habitat caused by changes in coastal land use as well as the shifting of our modern and local food systems, including the introduction of the invasive “gorilla ogo” (Graciloria salicornia). While at one time, there were countless species of limu being consumed in Hawaiʻi, it is now tough to find 20

Limu Kala, one specific species, is perhaps the most culturally significant and illuminates  how limu has played a vital role in Native Hawaiian lifeways for centuries. Medicinally, limu Kala can be used as a poultice to treat cuts and wounds, especially bacterial-like lesions caused by coral. 

Culturally, limu Kala (Kala meaning “to free” and “to forgive” in ʻŌlelo Hawaiʻi) is used symbolically in the Native Hawaiian conflict resolution process of hoʻoponopono. The use of limu in this emblematic way is found in no other culture in the world

From a culinary standpoint, in traditional Hawaiian diets, limu was the third component of a nutritionally balanced meal, in tandem with fish and poi. It provides minerals and vitamins, flavor, and spice. Limu is still a common ingredient in local Hawai’i-style dishes such as poke and stews. As the demand for limu has increased in recent years, this has unfortunately equated to increased production of invasive “gorilla ogo” to meet the demand, a species which is not a preferred food for native fish in Hawaiʻi and emerges quickly, overgrowing and choking out other seaweeds

The indispensability of native limu and the restoration of it is, for some, at the forefront of importance. In 2014, the first “gathering of gatherers,” a Limi Hui comprised of families and limu loea (masters) convened on Oʻahu, with ties from Molokaʻi, Oʻahu, Maui, Kauaʻi, and Kahoʻolawe all represented. The hui is committed to passing on the knowledge of limu, educating people, and supporting efforts to restore native limu in Hawaiʻi through community-based aquaculture and replanting. Other community groups have since been established.

On a state-wide scale, Governor Ige signed a “Year of the Limu” proclamation on January 28 of this year, acknowledging the work of limu loea and the organizations who are working to preserve limu knowledge and traditions. This designation for the year of 2022 will include mālama ʻāina workdays, invasive limu clean-ups, plantings, educational shoreline walks, and workshops on limu pressing and cooking. This proclamation serves to raise awareness and interest around limu, giving native limu its due attention as a vital component of our environment and communities in Hawaiʻi, as well as bringing it back to the table as a sustainable, delicious, and nutritious local culinary resource. 

Bringing Hawaiʻi’s native limu back to its former abundance will require more than individual hui groups–though they are a crucial part of the foundation–but also committed community engagement and a raised awareness in the young people who will eventually take over the role of limu stewards. 2022 may be the Year of the Limu in Hawaiʻi, but perhaps it should also mark the Return of the Limu, everywhere, for good. 
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