Finding the Balance: How Vital Research on Rockweed Harvest Helps Coastal Communities, Economies, and Ecosystems

Addressing a Data Gap and Community Questions

Rockweed (Ascophyllum nodosum)—an alga, not a fish, but still managed as a fishery by law—has been harvested for thousands of years on Maine’s coast, more extensively in the early 1900s, and on a commercial scale starting in the 1970s. When rockweed came to be harvested at a larger scale—and more visibly—some people in coastal communities had questions. They wanted to know if rockweed harvesting on a commercial scale was harmful for the ecosystem or the coastline at large.

Until recently, while small-scale rockweed harvesting studies had been done, no large-scale research projects had been undertaken, leaving policymakers, conservationists, commercial and recreational harvesters, and concerned citizens in the dark. In 2016, Maine Department of Inland Fisheries and Wildlife (MDIFW) and the US Fish and Wildlife Service (USFWS) reached out to researchers at UMaine, including Professor of Ornithology Brian Olsen and Associate Professor of Landscape Ecology Amanda Klemmer, concerned about the impact of rockweed harvesting on the ecosystems at large and specifically, shoreline birds. Seeing the potential for research to help achieve the intersecting goals of both coastal ecosystems and the coastal economy, Klemmer, Olsen, and their team were eager to design a research project that would answer the questions posed by coastal residents, conservation groups, policymakers, and the working waterfront community.

After conducting exploratory work with funding from the Maine Outdoor Heritage Fund and MDIFW, Klemmer and her team received $149,953 in Maine Sea Grant funds in 2018 to undertake a two-year project that came to be known as Conserving Rockweed Animal Systems for a Sustainable Harvest (CRASSH). The goal of CRASSH was to better understand the role of rockweed (and rockweed harvesting) in intertidal-invertebrate-bird food webs and engage stakeholders both in research design and in sharing research results.

Community Extension: Bringing Everyone to the Rockweed Table

“We knew from the beginning that for this project to be successful, we needed to actually bring all the stakeholders together and decide on a common goal for understanding this ecosystem and how it relates to harvest,” says Klemmer. With the help of Maine Sea Grant staff, the CRASSH team held several stakeholder listening session workshops.

“Commercial rockweed harvesters, bird conservation groups, and land trusts all have a stake in what goes on on the coast and with rockweed, but they don’t always have the opportunity to sit at the same table and problem solve together,” says Jaclyn Robidoux, a marine extension associate with Maine Sea Grant who worked on the CRASSH Project. That’s where the value of Maine Sea Grant’s extension team comes in. It was also the point at which the project really started to take off, “because of Sea Grant’s team and the connections they have with all the coastal communities,” says Klemmer.

“When you’re doing a project about a resource, there’s a risk in being limited in your thinking about who might be impacted by the research,” says Robidoux, noting how crucial it is for community engagement on research projects to be front-loaded rather than an afterthought. “It’s important not just to let people know that you’re doing research but to help them to understand the role they can play in it and know that their input is going to show up down the line.”

While the motivations of stakeholders who came to the listening workshops varied widely, all wanted similar outcomes for the research: to have access to objective data exploring the impacts of commercial rockweed harvesting on coastal ecosystems.

Klemmer mentions a picture that was taken at the end of one of the sessions of all the workshop participants standing close to each other and smiling. Reflecting on this moment, Klemmer notes how incredible it was to have assembled a group of people who historically had not gotten along very well due to competing interests and divergent opinions about rockweed harvesting and have a powerful conversation coalescing around how the rockweed research could help all of them.

Aligning Research Methodology with Real-Life Commercial Rockweed Harvesting

Rockweed is a complex, regulated fishery. While researchers knew this at the outset, they didn’t fully internalize the extent to which the regulations, as well as logistical and physical limitations, would impact their research design until after the stakeholder listening sessions. Listening to and learning from commercial rockweed harvesters was essential to developing a research methodology that would mimic how commercial harvesting is actually done, thereby creating more useful and reliable data, says Klemmer.

Commercial rockweed harvests are typically done via boat, with harvesters raking the rockweed as the boat drifts along the coastline. Harvests target a large spatial area, but “the amount of actual rockweed habitat that’s impacted with each swing of the rake is a lot smaller than what you would get if you went and clear-cut a whole patch of rockweed,” says Klemmer. Previous rockweed studies had been done at a small scale, with scientists cutting rockweed themselves in small, two-meter by two-meter patches.

“We always knew that we wanted to do a study on commercial-scale harvest,” Klemmer says. “When we originally designed the experiment, we had planned to have different severities of harvest to see a continual scale of the harvest response. Through conversations with commercial harvesters, we changed our design, and because harvest is so variable across the state, we ended up getting a nice continuum of sites.”

Collaborative research that draws on industry expertise yields better experimental design and better outcomes, says Jessica Muhlin, Professor of Marine Biology at Maine Maritime Academy, who was also part of the CRASSH team. “Scientists can be really helpful in thinking about theory, but so long as everyone’s good faith is in it, partnering with harvesters allows there to be a real application [of industry expertise] in the field [experiments].”

Unplanned Door-to-Door Rockweed Education Campaign

Throughout the project, a number of obstacles arose—COVID, for one, but more significantly, in 2019, the Maine Supreme Court ruled that the rockweed in the intertidal zone is owned by upland landowners, meaning harvesting rockweed in intertidal zones could no longer be done without landowner permission. The ruling, which landed in the middle of the CRASSH project, meant that researchers now needed to get permission from over 100 landowners in order to be able to carry out the research at the planned sites (38 in total). This unforeseen hitch took significant resources to smooth out, mostly in the form of two committed PhD students tasked with knocking on over 100 doors to get landowner permission to access the intertidal zone for the rockweed project.

“It changed the nature of some of the outreach,” Robidoux says, “People had lots of questions about the research when they saw that there was now a legal decision at play, whereas before, they wouldn’t have thought about it in the same way.”

While going out and knocking on the doors of so many landowners was not originally part of the project design, it allowed for a lot of meaningful outreach. The team suddenly had an opportunity to communicate directly with landowners about rockweed itself, why the research was happening, why it’s important, and what it meant for them as landowners. In addition, says Muhlin, the outreach helped educate the public on how commercial harvesting is done—not removing the entire seaweed—and to understand that “Maine has some of the most conservative rockweed harvest regulations out there.”

The Results Are In: Rockweed is Resilient

“The reason why we wanted to do this research in the first place is because we wanted to provide the working waterfront community, and state and federal management agencies with the tools and data they need to make informed decisions. There are real people that these data are affecting,” says Klemmer.

While there’s variation across the different CRASSH study sites, the data revealed that entire rockweed beds can and do recover from harvest and that commercial harvest has a smaller impact on algae, birds, and invertebrate organisms that live on rocks in the intertidal zone than previously thought.

Klemmer says that the findings were surprising to her in some respects, particularly in regard to how patchy commercial harvesting is. In a 100-meter stretch, harvesters would report removing four to five tons of rockweed in a single harvesting event. “Even though harvesting that amount seems drastic, after we did the estimates of how much rockweed was actually at those sites, we found that the total percentage that makes up the whole rockweed bed wasn’t as large as you would expect.”

“The CRASSH data show that rockweed is exceedingly resilient, and that it can be sustainably harvested,” says Muhlin. She also notes that harvesting is but one of many factors impacting rockweed, others including warming waters, storm disturbances, and ocean acidification. The intertidal zone is a dynamic place, always changing. It’s imperative that policies take this dynamism into account, and that research continues to help us better understand how both human activities in local contexts as well as larger habitat-wide factors impact the ecosystems at large.

With rockweed continuing to be part of legal conversations around ownership and access in Maine, the CRASSH project has another contribution to offer in addition to the data: relationships. “As a result of the CRASSH research,” says Robidoux, “these relationships have been strengthened. When things have gotten more intense due to evolving issues, the strength of these relationships has helped each unique stakeholder group weather it together.”

For more reading on the CRASSH project, check out: https://klemmeramanda.wixsite.com/crassh