By Ela Keegan
Reviewed by: Shep Erhart, Seraphina Erhart, Jaclyn Robidoux, Chris Petersen, Natalie Springuel, Gaelen Hall
“the world’s last great
renewable natural resource
and a culinary treasure
ready to be rediscovered”
-Kaori O’Connor, Seaweed: A Global History
This exploration focuses on the current uses of seaweeds, especially sea vegetables, their harvesting, and their farming from the 1960s until today. It teases out the differences between rockweed and sea vegetables, takes a look at the changes in the fishery, and explores the communities of people and industries surrounding sea vegetables today.
For more information on seaweed’s biology, the history of harvesting seaweed, and uses of edible sea vegetables by our earliest ancestors, please read Fisheries Then: Seaweed.
Uses of Sea Vegetables in Downeast Maine
On the consumer side of the edible sea vegetable industry today is a flourishing and creative array of products, consumables, and art. From Maine Coast Sea Vegetables (MCSV) sesame kelp krunch to Fog Town Brewery’s seaweed ale, sea vegetables are quickly seeping into the daily diet of Downeast Mainers. Born from family companies such as MCSV, the sea vegetable fishery has firmly established itself as part of a Downeast area’s cottage industry (White, 1992). Recipes such as kelp infused custard (Shetterly, 2018), lemon-ginger-alaria salad (Maine Seaweed LLC), New England dulse chowder (Downeast Magazine) and other creative concoctions are freely available in books and online. Through events such as the Maine Seaweed Festival (2014-2015), Maine Seaweed Fair, the Maine Seaweed Trail, and the Seaweed Symposium, Maine continues to celebrate what Redmond calls the “beautiful, healthy, living sea plants, in our own backyard” (Sneddon, 2015). However, unlike past inhabitants of the coast of Maine, seaweed has also become a romantic and artistic aspect of the Downeast rugged coast. Writers, sculptors, chefs, soap makers, cosmetic producers, painters, mixologists, and nutritionists all feature or use seaweed in their work. This work continues to highlight the value, mystery, and diversity of sea vegetables on the coast of Maine as a whole. Some of this work includes artist Celeste Roberge, poet V. Gail Tobey, owners of skin care company Dulse and Rugosa, and owner of SaltWater Studio Mary Jameson.
A Breakdown of the Downeast’s Seaweed Industry
Today, on the coast of Maine, there are over two hundred and fifty species of marine macroalgae, of which 11 are commercially and recreationally harvested. At fifty years old, the established seaweed industry in Maine, compared to other fisheries, is still relatively young.
Though we tend to lump all seaweeds together as one category, it is important to understand what distinguishes seaweeds from each other. Biologically, seaweeds are separated into three groups: the browns, the greens and the reds. However, economically and socially, seaweeds in Maine are separated differently, into two categories: rockweed (one of the browns) and sea vegetables (mostly reds and greens, and some limited food use of the browns).
Maine’s Commercially Harvested Species
All eleven of the seaweeds commercially harvested in Maine can be considered edible sea vegetables. Seaweed recovers its biomass at different rates, because of differing life cycles and rates of growth (Maine Seaweed Council, 2019). [To find more details on description, habitat, biology, sustainable harvesting practices, and handling of each sea vegetable species harvested in Maine look at the “Harvester’s Field Guide to Maine Seaweeds” produced by the Maine Seaweed Council in 2014.
All eleven species of edible seaweeds are listed below and are written by their scientific name and commonly used name(s):
- Palmaria palmata, Dulse
- Ulva lactuca, Sea Lettuce
- Chondrus Crispus, Irish moss, “Moss”
- Porphyra spp. Pyropia spp. and Wildemania spp, Nori, Laver
- Alaria esculenta, Winged Kelp, Edible Kelp, Alaria
- Laminaria digitata [syn Saccharina digitata], Fingered Kelp, Horsetail Kelp, “Digitata”, Oarweed Kelp
- Saccharina longicruris [syn Laminaria longicruris]
- Saccharina latissima [syn Laminaria saccharina], Sugar Kelp
- Ascophyllum nodosum, Rockweed, Knotted Wrack, Knotted Kelp, Egg Wrack
- Ascophyllum nodosum Fucus vesiculosus, Bladderwrack
- Ascophyllum nodosum ecad scorpioides, Worm Weed
Note that the last three on the list of 11 edible seaweeds are brown seaweeds, including: rockweed, bladder wrack, and worm weed. These three are not always classified as sea vegetables because of their higher industrial uses. For example, Ascophyllum nodosum, or rockweed, which is wild harvested with a boat using a mechanical harvester, bladed rake, or a knife (Arbuckle et al, 2014), is processed to make concentrated alginic acid used for plant fertilizers, soil amendments, nutritional supplements for plants/animals and then, in lesser amounts, for cosmetics (The Seaweed Site, 2014). Though most uses of rockweed are other than edibles, rockweed is sometimes blended with other brown, red or green seaweeds into food products, such as tea.
Rockweed has proved to have fast regeneration and is said to recover its biomass completely two years after harvesting (Arbuckle et al, 2014). It has historically been harvested in much greater numbers than other sea vegetables. In 2018 alone, 20 million pounds of wet rockweed was landed. This rockweed, before processing had a raw value of $0.9 million dollars (Rockweed Landings Data Graph, 2019). Rockweed has a relatively low value at around 4 cents per wet pound (M. P, 2016). In Maine’s four major rockweed companies there are currently a total of two hundred and twenty-five employees, including one hundred and fifteen harvesters and one hundred and ten waterfront and plant workers (Thayer, 2013). It is estimated that the rockweed industry as a whole has a value of $20 million dollars per year on the coast of Maine (Thayer, 2013).
Red and green sea vegetables on the coast of Maine are harvested by hand (without machinery) from wild populations. Unlike rockweeds, sea vegetables are also increasingly grown and harvested in aquaculture operations, for both commercial and recreational purposes. While each species of sea vegetable can be used differently, there are trends between how they are used based on how they are harvested. The majority of aquacultured seaweeds are used in “fresh” products such as seaweed salads, smoothies, and canned products. Wild harvested and some farmed species are typically dried and used in a variety of cooking, flavoring, and even alcoholic beverages.
Seaweeds have roughly a 10 to 1 wet to dry ratio. This means that dry seaweed weighs one tenth of its original wet weight. In Maine, most edible sea vegetables are dried by wild harvesters or farmers before being bought by processing companies, such as Maine Coast Sea Vegetables, who then resell final products. Therefore, sea vegetable harvesters receive a higher value for their product than rockweed harvesters, which is sold by harvesters wet, because of the increased labor involved in harvesting and processing sea vegetables (Erhart, 2019). In 2018, a total of 221,360 lbs. of sea vegetables were landed (The Maine Seaweed Festival, 2019). The value per pound can vary from $15 in bulk, up to $50 when manufactured into supplements (Maine Seaweed Council, Working Waterfront).
Despite not having consistent and clear documentation of sea vegetable harvesters, landings, and prices, it is possible to estimate numbers. Out of the 133 commercially licensed seaweed harvesters in Maine, 115 were rockweed harvesting. This leaves around 15 commercially licensed harvesters who were either solely harvesting sea vegetables or harvesting a combination of seaweeds.
A matter of scale: rockweed compared to edible sea vegetable industries
Seaweed on the coast of Maine has been a growing industry since 2001. The wild harvested rockweed and sea vegetable industries are legally managed as fisheries by the state of Maine through the Department of Marine Resources (DMR) who overseas commercial and non-commercial licensing, monitoring, research and law enforcement, as well as creating guidelines through which harvesters can sustainably collect and sell seaweed as a whole.
The main differences between the sea vegetable and rockweed industries in Maine is their scale. In 2018, the seaweed industry peaked at 22,436,544 lbs with a value of $921,818 (DMR, Historical Maine Seaweed Landings, 2019). Rockweed makes up 96% of Maine’s total seaweed landings, with the remaining 4% representing the 10 other commercially harvested sea vegetables (MDMR, FMP for Rockweed, 2014). Landing data from 2015, broken down by species and number of harvesters, documents that rockweed harvesters landed 14,109,094 wet pounds with a total of 50 harvesters (Seaweed Council, 2018). Wild sea vegetables harvesters landed 211,149 live pounds with a total of 67 harvesters.
Currently, despite the different scales at which sea vegetable and rockweed harvesting occurs, for management purposes, they are combined under the category of seaweed. This means that management, harvesting limits, and laws pertaining to or determined by one of these industries will most likely affect the other. An example of this is the 2019 court case in which rockweed was declared to be owned by the shorefront property owner. While this case originally only applied to rockweed, the DMR has since stated that the court decision likely applies to all intertidal seaweeds. It is therefore important to be aware of the differences between these industries when considering the sustainable capacity and management of each individually.
The remainder of this article focuses specifically on sea vegetables.
Sea Vegetable Harvesting
Turning our attention specifically to sea vegetables (and not rockweed), sea vegetables are harvested one of two ways; (1) wild harvested by hand (2) grown and harvested through aquaculture or sea farming operations.
Sea Vegetable Wild Harvesting
Wild harvesting is the collection of sea vegetables from intertidal or subtidal lands which are not cultivated or maintained. For the wild seaweed harvesters of Maine, access to the resource would, depending on the species, include walking down an intertidal zone, standing on submerged rocky ledges, or diving down to deeper species. Wild harvested sea vegetables on the coast of Maine are all collected by hand from a variety of locations. The main tools needed are a boat, a knife, and a basket/bucket. Harvesters typically harvest at low tide in order to have easier access to intertidal and subtidal species. The average wild harvester works from around March until December; however, the exact month differs from person to person (Woodcock, 2018). It is legal to harvest year-round, but water temperatures during the winter months limit and dissuade many from working this time.
Harvesters promote sustainable practices
As the seaweed industry started growing in the 1980’s, the harvesting community felt that the lack of existing regulations left the resources vulnerable to a potential for unsustainable practices. They decided to create an industry association to address challenges they felt that the state was not yet prepared to tackle.
The Maine Seaweed Council was founded in 1993 by seaweed harvesters, business owners, researchers, and consultants. The council supports a network of commercial and recreational harvesters by “managing seaweed natural resources for fairness and sustainability, training new harvesters and those looking to start seaweed businesses, and educating the public as well as law makers and resource managers about the benefits of seaweed for human and animal health and use in agriculture” (Maine Seaweed Council, 2019). They provide resources on sustainable practices for commercial and recreational harvesters, such as: “Harvester’s Field Guide to Maine Seaweeds” and “Harvest Guidelines for Maine Seaweeds.” Sustainable is defined as “simply being able to return to the same bed, year after year and take approximately the same quantities” (Maine Seaweed Council, 2019).
In 2013, the DMR began to develop statewide management plans for seaweed with recommendations provided by the Maine Seaweed Council. Due to different seaweed species having different “life cycles, growth rates, and tolerances for stress,” the DMR started by creating a plan specifically for Maine’s rockweed (Maine Seaweed Council, 2019). Even after this plan was developed, the DMR was unable to implement it because of the court decision (mentioned above) that was underway at the time regarding who owns rockweed in the intertidal zone. Though the court case regarding rockweed has been ruled (in favor of the upland landowner), the DMR is still (as of 2019) researching and creating a management plan for the rest of Maine’s harvested seaweeds, including sea vegetables. Until such a management plan is implemented, the Maine Seaweed Council created guidelines which outline best practices for a sustainable harvest (Maine Seaweed Council, 2019). These guidelines include a qualitative list of advice (found here) from Shep Erhart, founder of Maine Coast Sea Vegetables, as well as recommended harvest season, harvest height, and percentage of biomass removal for each species (found here). Biomass is the total quantity or weight of a species in any given area (Oxford American Dictionary, 2019). The council advises, dependent on the species, that between 30% and 75% of seaweed’s original biomass is harvested. These percentages per species are based on the collective knowledge of MSC members. They advise and encourage all harvesters to keep notes throughout the year in order to observe trends and changes. In order to develop more accurate information, MSC also encourages the sharing of public evidence or observations on seaweed populations. Through these inputs, new ideas on how to sustainably harvest continue to arise. While there is still no concrete management plan, the DMR still controls certain aspects of commercial and recreational seaweed harvesting through licensing. These licenses apply to all species of seaweed.
Licensing requirements for wild harvesters
Before harvesting seaweed on the coast of Maine, a commercial harvester needs to obtain a “Seaweed Permit” through the Department of Marine Resources. Recreational harvesters are not required to have a permit as long as they harvest less than fifty pounds a day for noncommercial use. Each harvester with a permit is required to keep daily notes on harvesting activity for all seaweed species and report this to the DMR once a month (DMR Chapter 8-Landings Program, 2003).
As for dead seaweed, Maine gardeners and farmers have long collected dead seaweed washed up in beaches beaches for their gardens. This is legal. According to the law, you are not required to have a Seaweed permit if you are “harvesting, possessing, shipping, transporting or selling seaweed that has detached naturally and is dead (DMR Seaweed Permit, 2018)
It is important to note that, as a result of the court case on the ownership of intertidal land and therefore species that grow there, all commercial and recreational harvesters must obtain landowner permission for the harvesting of intertidal species.
Sea Vegetable Aquaculture
Aquaculture, or seaweed farming, is different than wild harvest, though some of the same edible seaweed species that are wild harvested are also now farmed. For sea vegetables in Maine, aquaculture is predominantly done by growing seaweed on lines tied between buoys in the ocean. Between September and October, in the late summer months, seaweed planting begins (Redmond, 2014 and 2015). Lines and nets are “seeded” in a nursery on land, by soaking a rope in seaweed spores (Sea Grant, Kelp Aquaculture).
Kelp, for example, has a two-part sexual reproductive cycle. The first part includes a brief microscopic stage (gametophyte). The second lifecycle happens on the spools, where the gametophytes develop into male and female filaments which release another set of spores that produce the small blades on the line. When the algae grows to a juvenile length, they are transferred on the lines into the ocean to grow from November to sometime in Spring. Sea vegetables are a winter crop, with a growing season between fall and spring. During these months, farmers continue to check their lines, optimizing their position in the water and observing seaweed growth (Redmond, 2014 and 2015). Sometime between March and April, dependent on the species, aquacultured seaweeds are harvested. In Maine, in order to avoid the busier summer months on the water and the risk of biofouling (pollution and ruining of a seaweed crop), all sea vegetables are typically harvested by the beginning of the summer months and the ropes brought onto shore (Redmond, 2014 and 2015).
Management of Sea Vegetable Aquaculture
Though seaweed farming is quite new in Maine, the regulations developed for finfish and shellfish aquaculture lease applications apply to seaweed too. All sea vegetable aquaculture taking place in marine coastal water requires a lease which is managed by the DMR. While there are no harvesting limits on seaweed aquaculture, farmers are limited by the area they are licensed to farm, which is determined by their lease. Perhaps the most important aspect of seaweed aquaculture is the location of their site. Farmers must take the “physical, biological, environmental, and human aspects of the site” into consideration (Sea Grant, Kelp Aquaculture). It is important to be aware of potential hazards and pollution in nearby water that could affect the quality or safety of the seaweed. An example of one consideration made by Sarah Redmond is the choice of ocean bottom over which to farm. She says, “growing seaweed over mud is good husbandry because it doesn’t impinge on wild habitat to create a cultivated system” (Shetterly, pg. 141).
Due to the DMR’s confidentiality statute (found here), which aims to protect the confidentiality of personal data, harvesting data of farm-raised marine algae in Maine is only available starting in 2015 (found here). In 2015 there were four DMR licensed entities who reported harvesting a total of 14,582 wet lbs of farm-raised algae to the Maine DMR. In 2016 this increased to 24,004 wet lbs by six entities, and again to 45,023 wet lbs by eight entities in 2017. Last year, in 2018, this report peaked at 53,564 wet lbs by 16 different entities in Maine (DMR Harvest of Farm-Raised Marine Algae in Maine, 2018). These farms, along with other aquaculture sites can be seen on the “Maine DMR Aquaculture Map”.
Support for the growing seaweed farming industry
Maine’s coastline has historically been a location of high productivity for seaweeds. Along with increased technology and research, the Downeast area is growing as a globally important resource for edible and commercial seaweeds. Some proponents feel this provides valuable opportunities for diversification of Maine’s fisheries and production which could healthily sustain future generations. Others caution it could make Maine’s coast vulnerable to privatization, unsustainable management, and harmful harvesting practices. Harvesters and farmers in the Downeast area are keenly aware of the importance of keeping the edible sea vegetable industry sustainable. The communities around sea vegetables today are continuing conversations through different councils and meetings to vocalize and address such concerns. With the world’s history of collapsed and unsustainably managed fisheries, the young sea vegetable industry in Maine continues to fight to remain within sustainable limits. As Shep Erhart, founder of Maine Coast Sea Vegetables, says, “sustainability is a key issue; this is one of the few fisheries that still has a chance at sustainability.” (Jacobsen, 2017)
For more information on seaweed’s biology, the history of harvesting seaweed, and uses of edible sea vegetables by our earliest ancestors, please read Fisheries Then: Seaweed.
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