By Megan Diebboll
Animals hold a critical yet often overlooked role in urban planning, embodying resilience in ecosystems shaped and reshaped by human hands. Among them, oysters have demonstrated a remarkable capacity to endure, forever shapeshifting with the relentless tide of urban change. Until the twenty-first century, oysters flourished in New York Harbor–in fact, New York City was once celebrated as the Oyster Capital of the World. For centuries, oysters were not only a culinary staple but also a cultural symbol of abundance and prosperity. In 1609, approximately 350 square miles of oyster reefs stretched across the harbor, with some oysters growing as large as ten inches in diameter. To early New Yorkers, oysters were more than just food; they embodied the richness of the harbor and the sense of possibility that defined the city.
NYC’s streets are quite literally paved and created by oysters; they could be considered the first urban planners or landscapers of the city. Pearl Street in the Financial District is named for a massive oyster midden that once stood there before the Dutch built the street on top of it. New York’s oysters didn’t make pearls, but the crushed shells shimmered with a pearly sheen, scattered across the ground like a quiet reminder of the city’s once-rich waters. Additionally, stone buildings like the iconic Trinity Church at Wall Street and Broadway are still held together with mortar made from oyster shells, ground into a strong, chalky paste.
As with so many things in New York City, waste played a key role in the downfall of the oyster dominance. Despite containing half of the world’s oysters in the seventeenth century, the lower Hudson estuary’s oyster industry was ultimately wiped out by pollution and overharvesting. But they weren’t gone for good. In the early 2000s, oysters reemerged through ecological restoration; by the 2010s, they were woven into urban design and policy. Today, they’re part of New York City’s living infrastructure.
Oysters as Infrastructure: Marine Ecosystem Health and Shore Mitigation Efforts
Oysters are undeniably resilient and ecologically essential creatures, deeply woven into the history and infrastructure of New York City. Oysters provide critical environmental services that strengthen urban coastlines against climate threats through marine ecosystem health and shoreline mitigation efforts.
Oysters are powerful contributors to water filtration and overall ecosystem health. A single oyster (average size of three inches) has the ability to filter up to fifty gallons of water per day, effectively removing pollutants, excess nitrogen, and regulating algae growth to prevent harmful algal blooms. This natural filtration process improves water clarity, supports the growth of underwater vegetation, and promotes marine biodiversity by creating healthier aquatic environments.
Beyond water filtration, oysters play a crucial role in supporting marine biodiversity. By reducing nutrient overloads, they prevent harmful algal blooms, which can otherwise damage marine life. Oyster reefs themselves act as complex structures that provide essential habitats for a wide range of marine organisms. These reefs also serve as nursery grounds for juvenile fish and other marine creatures, supporting the food web by offering a valuable food source for larger species like fish and crabs.
Inspired by efforts like these, New York City takes its cues from the Chesapeake Bay model, integrating oysters into its own coastal restoration and water quality strategies. Led by Dr. Suzanne Bricker of NOAA’s National Centers for Coastal Ocean Science, oyster farmers, and state environmental agency officials, the Chesapeake Bay Restoration focuses on revitalizing oyster populations to enhance water quality and sustain local fisheries. to expand oyster aquaculture in the Chesapeake Bay region. This initiative aims to boost the local economy while improving water quality in the bay. By filtering algae, oysters help remove harmful elements like nitrogen and phosphorus, improving water quality. For example, in Chesapeake Bay, adding one million three-inch oysters can eliminate nearly 200 pounds of nitrogen and twenty-two pounds of phosphorus, a fact that led to the inclusion of oyster tissue in nutrient management plans.
In New York, the Billion Oyster Project is a nonprofit organization dedicated to restoring oyster populations in New York Harbor to improve water quality and coastal resilience. Its restoration of oyster reefs throughout the harbor directly supports shoreline resilience. By installing reef structures in strategic intertidal and subtidal zones, the project enhances both ecological function and physical shoreline protection. These efforts integrate nature-based solutions into urban coastal defense systems, complementing gray infrastructure and advancing climate adaptation goals.
One of the oyster’s most important roles is creating a natural breakwater, reducing wave energy and mitigating storm surge damage. By stabilizing shorelines, oysters help prevent erosion and protect cities from flooding. Oyster reefs function as living infrastructure that significantly reduces coastal vulnerability. Their three-dimensional structures attenuate wave energy by increasing bottom roughness and disrupting wave momentum, which decreases the height and force of incoming waves before they reach the shoreline. This natural breakwater effect lowers the risk of storm surge damage during extreme weather events.
Additionally, by fostering sediment deposition and stabilizing substrates (underlying surfaces like sand or rock), oyster reefs combat coastal erosion. They slow water flow, allowing suspended sediments to settle and accumulate, which can lead to vertical accretion over time. This process is vital for adapting to sea-level rise as it promotes the elevation gain needed to keep pace with rising waters.
During the month of May, I volunteered with the Billion Oyster Project on Mondays for their public Oyster Research Station (ORS) monitoring sessions. Our crew met at Brooklyn Bridge Park’s Pier 5, where small-scale oyster habitats hum with life. These stations function like underwater apartment complexes, containing oysters and attracting a vibrant community of marine organisms, including crabs, shrimp, sea squirts, and biofouling species. One of the staff members even reported spotting seahorses during a recent session, a promising indicator of increasing biodiversity.
Each week, we conducted field monitoring using standard ecological protocols: measuring oyster shell height as a proxy for growth, recording mortality rates, and documenting associated invertebrate species. This data helps track the health of restored reef sites and contributes to long-term urban estuary science. Oysters, as keystone species and natural water filters, play a critical role in improving water quality and supporting marine food webs. The work I did supports the Billion Oyster Project’s goal of restoring 100 billion oysters to New York Harbor by the end of 2035, contributing valuable data toward assessing reef viability and ecological impact.
The return of oysters to New York Harbor is less a story of reinvention than one of reconnection, of catching up to a past in which nature and city once thrived together. As we face rising seas and environmental uncertainty, these resilient creatures offer a model for how urban planning can align with ecological wisdom. It was heartening to see such a wide range of people involved; kids, seniors, couples, and scientists all drawn together by a shared curiosity and care for the harbor. Clipboards in hand, surrounded by the salty breeze and the sound of lapping water, we became part of the slow, steady pulse of resilience, one oyster at a time.
Megan Diebboll is an urban planner, social worker, and artist working to create and sustain liberating environments in green and public spaces across New York City. She focuses on maintaining and strengthening the social and physical infrastructure that makes shared spaces feel safe, welcoming, cared for, and grounded in community.
Additional sources:
Vital Choice. (2022, November 15). How Oysters Built New York City. https://www.vitalchoice.com/articles/food-facts/how-oysters-built-new-york-city
New York Public Library. (2011, June 1). The History of the Half Shell: An Intertwined Story of New York City and Its Oysters.
Billion Oyster Project. (n.d.). New York Harbor history.
Chesapeake Bay Program. (n.d.). Oysters. Chesapeake Bay Program. https://www.chesapeakebay.net/issues/whats-at-risk/oysters
One Earth. (2023, June 8). Oysters: Nature’s Water Filtration System.
NOAA National Centers for Coastal Ocean Science. (2021, July 15). Water-cleaning Capacity of Oysters Could Mean Extra Income for Chesapeake Bay Growers [Video]. https://coastalscience.noaa.gov/news/water-cleaning-capacity-of-oysters-could-mean-extra-income-for-chesapeake-bay-growers-video-2/
