Meredith Comi reefs what she sows. Beneath a pier at Naval Weapons Station Earle in Leonardo, five temperature-controlled tanks full of brackish Raritan Bay water serve as nurseries for millions of oyster larvae. Comi, the Monmouth University Urban Coast Institute’s (UCI) coastal resilience and restoration practitioner, monitors as they bond to submerged concrete blocks, called oyster castles, and grow strong enough to survive in the wild.
On a brisk November day, 80 castles were removed from the tanks and began a journey to join an artificial reef composed of 500 more off the base’s shoreline. Staff from the UCI, Navy, New Jersey Department of Environmental Protection (NJDEP), National Oceanic and Atmospheric Administration (NOAA) and Rep. Frank Pallone’s office rapidly loaded them aboard a truck bound for Atlantic Highlands, where they were placed aboard Monmouth’s R/V Heidi Lynn Sculthorpe, steamed to a spot a few hundred yards from shore, and transferred to Monmouth’s R/V Seahawk. The smaller vessel could then safely transport a few dozen castles at a time to the shallow waters surrounding the reef, where they’d be stacked in pyramid formations.
The research being conducted at the reef is restoring the environment while producing valuable data on the power of nature-based solutions for improving coastal resilience. Oysters are famous as nature’s water purifiers, with one adult capable of filtering excess nitrogen and pollutants from 50 gallons per day. But what impresses Comi most is their skill as ecosystem engineers. Like the corals of the Caribbean or Australia, they are a keystone species that builds reefs that provide refuge and breeding grounds for other organisms.
“We live in an area where there’s no substrate on the bottom. We’ve bulkheaded everything,” Comi said. “When you put in an oyster reef, all of the species diversity that comes with it makes the biological community so much more rich.”
It can also help climate-proof a shoreline. The research at Earle began in the wake of Superstorm Sandy, which devastated surrounding Bayshore communities. As the reef structures accumulate sediment and become further armored by the oysters and other organisms growing on them, they can serve as “speed bumps” that blunt the force of waves and prevent erosion. The Department of Defense was interested in the reef’s potential as a coastal protection and offered access to roughly 11 acres of its waters, as well as 3,200 feet of its beach as part of connected research on living shorelines defenses.
Earle offers unique advantages as a test site. Because the waters are strictly off limits to civilians, there’s no chance the oysters can be fished or disturbed by boaters. At the same time, the area presents all of the challenges and research questions for growing oysters in the dynamic urban water systems typical of the New Jersey and New York coasts.
Comi has been building and nurturing the reef for about a decade, initially for NY/NJ Baykeeper, which transitioned the project to the UCI in 2023. The research has expanded under the umbrella of the UCI’s Coastal Community Resilience Initiative, with a team consisting of Comi, UCI Marine Biology Technician Amanda Boddy, Associate Director Tom Herrington, and marine and environmental biology and policy student Lexi Baumgartner. The work has been supported over the years by National Fish and Wildlife Foundation grants and Congressional investments secured by Pallone, which covered the purchase of reef materials, oyster larvae, equipment, and the aquaculture tanks at Earle.
Trial and Error
Through the years, Comi has tested a variety of structures to see which were effective. There were broken hockey sticks, donated by area teams and repurposed to build reefs; bags and cages of used shells donated by seafood restaurants; porous “reef balls”; various metal cages.
A key lesson from the experiments has been that what has worked in other places is not guaranteed to in the tough waters of the Hudson-Raritan Estuary. Comi recalled that initial oyster restoration projects tried to mimic the success of efforts in the Chesapeake Bay which involved piling shells in mounds on the bottom. Baykeeper and partners attempted to do the same, but after one season, the strong currents and waves of the Raritan dissipated the piles. Even weighty reef balls that were tied together drifted away. Techniques need to be tailored to the specific characteristics of a project site.
The oyster castles offered a stability that other materials didn’t. Their weight (about 30 pounds each) and nubs on the crown of the blocks allow them to lock together like Legos and resist the water’s energy. New technologies in the works offer further promise.
“I’m really excited about the amount of substrates and structures available now,” Comi said. “It’s exploded over the past five years with these new products, which we’re going to be testing at Earle.”
In a literal – or shall we say littoral – case of art imitating life, plans are underway for Monmouth University Associate Professor of Art and Design Kimberly Callas to create structures that emulate oyster reef shapes using a 3-D printer. The success rate of these materials will then be compared with others to determine whether using shapes that are accurate to nature makes a difference.
Are the Reefs Working?
Oysters were once abundant in the Raritan and Sandy Hook bays. When Henry Hudson explored this region’s waters 400 years ago, the crew marveled at the reefs sustaining foot-long oysters, according to Rechnitz Family/UCI Endowed Chair in Marine and Environmental Law and Policy Peter Jacques. But as people flocked to the New York metro region, overfishing and degraded water quality all but wiped out the natural populations.
Today there are only a few small pockets of reefs surviving throughout the watershed. Most are just far enough upstream in the bay’s tributaries that they’re not exposed to its harshest conditions while still having access to saltwater.
Initially, the only oysters growing on the reef structures were those that were raised in the tank. However, this past summer natural set was observed, indicating oyster larvae has made its way down the Raritan Bayshore to Earle.
“Now that we have natural set, I think it will alleviate some of our issues with there being no oysters in the water, and we won’t have to produce them all ourselves,” Comi said. “Hopefully more will start navigating their way along the Bayshore.”
Success won’t come easy. On top of the difficult water conditions, natural predators, like oyster drills, lower their odds of survival. There is also a competition for space. Video footage captured by Boddy shows the reef is teeming with marine plants and animals.
“There’s a lot of life congregated around these castles,” Boddy said. “We see all sorts of fish, a lot of bryozoans, worms, snails, drills, crabs. We actually have seen tropical fish because the estuary is so productive.”
As part of a separate project at Sandy Hook, the UCI is working with scientists from New Jersey City University, NOAA, and the New Jersey Sea Grant Consortium to study whether colonization by other organisms is discouraging oysters from living on the castles.
The UCI is also engaged in a third oyster reef project that aims to stabilize an eroding marsh island area at Long Beach Township’s Clam Cove. Funded by New Jersey Resources, the project is studying the oyster recruitment and resilience benefits of an experimental arrangement that will surround bagged shells with oyster castles.
Collectively, Comi is hopeful these projects will improve the Jersey Shore’s marine environments and serve as models for others in the future.
“I would love for these projects to impact policy and decision-making in some way, whether it’s influencing the state’s shellfish rules or understanding the technologies and transferring them to other urban estuaries,” Comi said. “I would love to see what we have put in flourish and of course increase natural larvae in the system – and I think it is. I think that we’re going to see more and more natural oysters in this area.”