USA – When people think of farms, they tend to picture tidy rows of crops growing under abundant sunshine on terra firma. However, it turns out that not all farms are on land, and in fact some flourish in the sea. You have likely heard of shellfish and finfish farming, but a new type of cultivation is emerging in our region: seaweed farming.
“In the Pacific Northwest, we have one of the most diverse assemblages of seaweeds on the planet, and there are probably more applications for those species than we know of now,” said Meg Chadsey of Washington Sea Grant.
For many, the word “seaweed” likely conjures up images of decomposing plant-like matter cast upon the beach. Yet for others, like those in the Indigenous Aquaculture Collaborative Network, seaweeds are much more, having been cultivated and used for thousands of years.
Kelp, often referred to as seaweed, is a type of macroalgae that grows in cold, nutrient-rich marine waters. Under ideal conditions a single stalk of kelp can grow up to a foot in a single day, absorbing carbon dioxide in the process. Kelp forests provide essential habitat and nutrients for a variety of marine organisms like fish, sea otters and a host of invertebrates including sponges and bryozoans. Growing kelp also removes nitrogen from the ecosystem, which is helpful in reducing harmful algal blooms and the biotoxins they produce. Kelp also benefits humans in a variety of ways as well, with applications ranging from fertilizers and animal feed, to cosmetics, biofuels, bioplastics and nutritional products.
These are just some of the reasons why Joth Davis co-founded the first and only commercial seaweed farm in Washington’s coastal waters: a 2.5 acre space for cultivating sugar kelp called Blue Dot Sea Farm (BDSF). Together, BDSF, Washington Sea Grant, the Puget Sound Restoration Fund (PSRF) and other partners are researching the various benefits of kelp farming, and they are encouraging others in the area to take a closer look as well.
“Blue Dot Sea Farm was established to take advantage of the synergies associated with cultivating shellfish and seaweed in the same three dimensional water space,” says Davis. “We made the decision to commercially grow sugar kelp but wanted to first resolve the issue facing seaweed farmers nationwide: What can you do with all the seaweed we can grow?” To work out this end-use problem, Davis and the BDSF team are launching a seaweed based, organic, vegan snack food called Seacharrones.
A grant from the Paul G. Allen Family Foundation in 2017 funded a multi-year experiment at Blue Dot’s current kelp farm site to assess whether cultivated kelp could mitigate the localized effects of ocean acidification. Led by PSRF, this first-of-its-kind investigation leveraged expertise at the University of Washington, NOAA Pacific Marine Environmental Labs, Washington Sea Grant, state agencies and the private sector to measure the effect of kelp on surrounding seawater chemistry and marine life. The investigation spawned a number of new projects, and Sea Grant has since collaborated on several other in-house projects with BDSF and PSRF to better understand the role of kelp aquaculture in the environment and economy.
As research and partnerships around seaweed farming in Puget Sound grow, so has public interest in the promising industry. In response to this interest, Sea Grant, PSRF and BDSF also hosted an intensive 3-day workshop for 30 aspiring farmers in early 2020, designed to equip them with the knowledge, skills and contacts they’d need to pursue seaweed farming in Washington State.
As with any new industry, flourishing possibilities have been met with some obstacles. From a commercial production standpoint, challenges include finding a suitable location (a farm has to be located in open water with depths of at least 20 feet, with adequate water movement and dissolved nutrients), getting seed stock, working through adverse water conditions in the winter, permitting a farm and addressing user conflicts for space on the sea surface.
“Getting the permits to operate has been difficult and involved a great deal of outreach to stakeholders: Tribes, eNGO’s and local property owners. We operate BDSF within the Usual and Accustomed fishing areas of five Tribes that have important treaty rights to fishing in Washington State. We fully support the Tribes and their treaty rights and believe that growing seaweed and shellfish together has intrinsic and demonstrable benefits to the water and habitat with special regard to ecosystem services,” says Davis.
Other obstacles exist too, like the timely dissemination of scientific information to the burgeoning farming community, and the fact that many people often equate kelp farming to fish farming, despite the fact that it is a separate and less resource intensive form of aquaculture. As an added challenge for Sea Grant’s workshop, a train derailment near the Seattle ferry terminal nearly caused workshop participants to miss the chance to hear talks from experts and get out onto the water to the BDSF site.
Yet despite these obstacles, interest in kelp farming and research continues to grow. Sea Grant received so many applications to their 2020 workshop they had to limit enrollment. The workshop proved so successful that on the final day of training, they spontaneously decided to form a seaweed farming Community of Practice, which has met regularly to learn from and support each other.
Chadsey is enthusiastic about continuing to respond to the growing need for training, education and support for aspiring kelp aquaculturists. “Seaweed farming isn’t going to go away anytime soon, and networks like the Community of Practice can help people proactively ensure that the industry expands in a responsible way”, says Chadsey, “Washington Sea Grant wants to be part of this, in our role as a neutral convener and trusted source of scientific information, we can help stakeholders and the public make informed decisions about seaweed farming in Washington waters.”
In addition to fostering social capital, the field of kelp farming can also support important marine ecosystem restoration efforts and galvanize changes needed on larger scales.
“If I have learned anything in the 40 years I have been working at sea farming, it is that life in the Pacific Northwest, including ourselves, is intricately connected and that we need to restore and enhance these vital connections,” says Davis. “I think that farming seaweeds can assist in reconnecting parts of the marine environment to the whole by providing critical habitat and ecosystem services related to carbonate chemistry and other needs.”
Source: College of the Environment – University of Washington
