Lucy Dutton gears up for her 27th dive with Team Zostera for a pilot-scale eelgrass transplantation on Oct. 17, 2024. Laura Sitterly / The Times Record file photo

Seagrass is an unsung hero. It breaks the force of crashing waves, serves as a home for fish and juvenile lobsters, stores carbon dioxide, and pumps oxygen into the ocean. It's also in danger.

Scientists are working to restore what has been lost -- roughly half of the native eelgrass cover. If not to its original glory, then at least to something more expansive than the mucky bottoms left behind.

Related Groundbreaking eelgrass pilot restoration takes root in Casco Bay

Since 2021, the Collaborative for Bioregional Action Learning and Transformation's (COBALT) Team Zostera has surveyed the remaining seagrass meadows, identified the species' reproductive season and determined the best time for seed collection. Working with the Casco Bay Estuary Partnership, Friends of Casco Bay, Maine Department of Environmental Protection and the U.S. Environmental Protection Agency, the team has also started to explore solutions, including transplantation.

But they aren't the only ones in the arena. Eager to thread together work being done, researchers convened at the state's first seagrass summit on Jan. 14 to develop a strategy for large-scale restoration.

Related Casco Bay scientists tackle eelgrass loss

In October, Team Zostera diver and Bowdoin College senior Lucy Dutton helped scatter 40,000 seeds near Cousins and Little John Islands, just off the coast of Yarmouth. She has been busy working in the lab this winter, reserving some seeds to test germination rates.

Her studies seek to reveal how aquatic plants respond to stress, such as temperature and salinity changes, in Petri dishes -- knowledge that is vital for guiding future restoration along the East Coast.

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Data analysis is ongoing, but preliminary evidence corroborates numerous studies that find that lower salinity and higher temperatures produce algae growth conditions that stimulate seed germination.

The Times Record spoke with Dutton about the need for long-term data collection to better assess the seagrass situation and her plans to pursue a career in science after graduation during an "uncertain" time in history.

(Surprising) project takeaways

Dutton's research investigated how environmental factors affect seed germination and viability by counting the seeds produced by each shoot and those capable of germination.

Eelgrass shoots with seeds inside at the Coaster Schiller Studies Center. Lucy Dutton photo

Since Jan. 27, she has been analyzing the data -- a three-step process to ensure accuracy.

While the sample size, five shoots per Casco Bay site, was relatively small, some variation was found. Meadows in Long Island, for example, seemed promising. So, Team Zostera will swing by this summer to collect additional shoots.

Now that the crew knows how many seeds are produced per shoot, the next step is understanding how many reproductive shoots are at each meadow. Further work is required -- it's too soon to tell if temperature or salinity directly correlates to growth or lack thereof.

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"It's hard to create optimal growth conditions in a lab," Dutton said. "You just can't mimic the ocean environment. But what's encouraging is that as radically as the sea changes, there is still great potential for recovery. ... It would be be amazing to witness -- we've got to try."

Some things surprised Dutton. Even in the lab, planktonic guests and copepods crept in. Despite constant filtering, she found horse mussels and polychaete worms in the seawater tanks.

"Sometimes, reproduction is a sign of stress," Dutton said. "At Mackworth Island, we collected shoots with a bunch of seeds, few of which were viable. This could mean that the meadow was responding to poor water quality. On the other hand, at Long Island, we also did, and when diving, we saw clear meadows that appeared healthy enough to allocate nutrients to reproduction. So it's tough."

The takeaway? Reproduction rates might not be the best indicator of overall health. And since seagrass meadows fluctuate yearly, long-term data collection is key.

Lucy Dutton (left) and Allison Fogg carry PVC pipes to the Cousins/Littlejohn restoration site to form clear quadrants for the 2024 eelgrass pilot transplantation. Lucy Dutton photo

Other findings in the field

Unlike terrestrial planting, where soil amendments and environmental conditions for optimal growth are well known, researchers are beginning to understand the requirements for aquatic plant germination.

"The seeds didn't perform too poorly across different temperatures," Dutton said. "Salinity did. I tested two seawater levels: 32 parts per trillion (ppt) and 16 ppt. The germination rates were much higher in lower salinity."

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To enhance her research, Dutton read the work of other scientists in the field to gather valuable insights. She provided three specific examples.

The first was a study on seed bank development, germination and early seedling survival of two seagrasses from the Netherlands: Zostera marina and Zostera noltii. It determined the different reproductive windows for each species and then delved into optimal growth conditions -- Z. noltii survived best at 50 degrees Fahrenheit and 1% salinity, whereas Z. marina survived best at 50 degrees Fahrenheit and 10%-20% salinity.

Ultimately, the report revealed that if a seed bank is approached, eelgrass seeds must be rotated annually.

"I have a few seeds in the fridge right now," Dutton said. "Creating a seed bank in the lab isn't viable, though, since eelgrass doesn't live long. A natural seed bank could work. Research shows seeds can continue to germinate if planted under sediment, even if the existing seafloor cover is gone."

Dutton also illuminated a Canadian study that examined eelgrass reproduction dynamics at six sites on the Atlantic coast. The report claims that the robustness of natural seed banks is linked to shoot density, suggesting that resilience assessments include shoot density data to better inform conservation efforts.

Lastly, she referenced a study led by the Schiller Coastal Studies Center and Bowdoin College Department of Biology that was published in the journal Ecology last September.

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Findings emphasize that a better understanding of how other species, like oysters, interact with seagrass (macrophyte-bivalve) is vital for eelgrass restoration and the expansion of aquaculture.

Lucy Dutton eelgrass seed production findings at sites across Casco Bay. Lucy Dutton image

Pilot test check-in

The Cousins/Little John Island project was the first in the state to focus on seed harvesting, processing and redistribution.

That said, the transplantation -- nine underwater plots that tested seeding methods: hand-cast versus biodegradable seed-filled tea bags secured with bamboo skewers -- was done with hope but little science to back its success.

The last time the quadrants were checked, on Jan. 12, there was little activity. The meadows were still small and turf-like. Once the water warms, Team Zostera will implement growth-monitoring plans at both sites to determine when germination occurs and to what degree the seeds take hold on the seafloor.

"It's too soon to tell," Dutton said. "It's hard to be patient, but the seeds are still so tiny that even if they germinate, it will take a few more months until shoots appear."

Glenn Page and Lucy Dutton, Team Zostera divers, before monitoring Casco Bay seagrass meadows. Lucy Dutton photo

The importance of science communication

As she considers post-graduation plans, Dutton noted the challenges of pursuing a science career, especially since securing federal funding for research has become more difficult.

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"A focus in my classes has been about poor communication between scientists and the public," Dutton said. "I would encourage young scientists not to overlook the humanities. I double major in biology and English because I feel a holistic view of the world is important in the scientific field."

On Valentine's Day, Team Zostera turned to artists, musicians, philosophers and poets to bolster seagrass recovery efforts. The group held a workshop blending art, science and Indigenous wisdom at the Osher Map Library and Smith Center for Cartographic Education.

Related A Valentine's Day celebration of vital, overlooked eelgrass

The event featured the work of Eva Ahn, another Bowdoin College student who, last summer, worked with Team Zostera on an independent study of eelgrass botanical illustrations depicting the stages of seed development.

"The work Team Zostera is doing depends on volunteers," Dutton said, prompting locals to get involved. "You don't need a science degree to go snorkeling in an eelgrass meadow and find reproductive shoots. And it's fun!"

The collaboration between COBALT and Bowdoin College will continue, but Dutton's eelgrass work depends on undergraduate interest. Reflecting on her younger colleagues' passions, she anticipates a greater focus on the species' physiological aspects in the future.

Dutton's experience has strengthened her interest in conservation ecology. She is considering graduate school but plans to gain hands-on experience first.

"I feel it's important to establish a connection between theoretical knowledge and real-world applications," Dutton said. "I want to make a positive impact, but I'm figuring out how."

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