One Oyster at a Time, Restaurants Are Protecting NYC from Climate Change

Signs of New York City’s oyster heyday are hidden across Lower Manhattan. Pearl Street in the Financial District, takes its name from the valuable stone-like objects sometimes found inside oysters and whose shells built up and once paved the road; the mortar that binds Trinity Church opposite Wall Street is made from ground oyster shells. By the 19th century the city was known as the oyster capital of the world: oyster beds covered 350 square miles of the lower Hudson estuary and New York Harbor was estimated to hold half of the world’s known oyster population.

Today that’s no longer the case. Pollution and overharvesting devastated New York’s oysters; only in the last 20 years or so have efforts been made to rejuvenate the area’s saltwater mollusks.

That’s in part thanks to a partnership between the city’s restaurants and the nonprofit Billion Oyster Project. Together, with the backing of local government, they’ve worked to return used oyster shells to the waters surrounding New York City, which helps build a foundation from which new oysters can grow.

Oysters play a vital role in maintaining clean water and protecting shorelines. They are natural filters, which helps improve water quality for other aquatic life. And the giant clusters they form provide a buffer against waves and help protect sensitive marshland from eroding—critical ecosystem services in the face of climate-fueled storms and sea level rise. The oyster reefs also help boost the region’s biodiversity.

Launched in 2014, the project aims to restore 1 billion oysters by 2035. To achieve this, by next year it hopes to be able to restore 100 million juvenile oysters annually. So far, 18 oyster reef sites across the city’s five boroughs have been restored, and since launching its restaurant partnership program in 2015, more than 2 million pounds of shells have been collected from nearly 60 restaurants for their restoration efforts.

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One of the project’s earliest partners was seafood market The Lobster Place, which today is responsible for collecting restaurants’ buckets of used shells. The market itself also goes through some 20,000 oysters a week. It’s a “very symbiotic relationship for us,” says David Seigal, culinary director of The Lobster Place. “We have oyster shell waste, they need oyster shells to help build these reefs.”

Once the discarded shells are collected, they go into an open-air pile where they “cure” for up to a year. Baking under the sun, any residue left on the shells decomposes or is eaten, and any parasites or disease-causing pathogens are killed off. Next, the clean shells are put into retrofitted shipping-container tanks filled with water from the harbor and oyster larvae, which swim around before eventually settling on the shells. After a few weeks, the populated shells are released into the restoration sites; the shells nestle onto the surface of the growing reef where the larvae soon become adult oysters.

From being harvested to returning back to the water, “it’s a pretty wild ride for that shell,” says Mike McCann, a climate adaptation specialist at the Nature Conservancy, which previously helped the Billion Oyster Project select its restoration sites and develop methodology to measure success. While the project, along with a handful of other nonprofit initiatives and schools in the area such as the Hudson River Foundation and the Urban Assembly New York Harbor School, have been steadily building up New York’s oysters, McCann estimates it’s still only a fraction of what it once was: “To get that population back to a place where it can be self-sustaining is going to take a lot of effort and a lot of really good science.”

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This year has also seen its challenges. While the project added 12 new restaurants to its shell-collection initiative in 2023, wholesale seafood sales, including oysters, have been down since the summer, says Boesch. She says this is in part due to oysters’ high price tag as well as the cost of labor for shuckers, which is rising as a result of labor shortages and the city’s increased minimum wage laws. “Due to changes in diner behavior in NYC, particularly in midtown Manhattan, we are looking to engage smaller partners and neighborhood restaurants,” says Boesch about plans for next year.

Of course, it’s also important to remember what these oysters aren’t able to be: food. In addition to persistent pollution, city wastewater still flows into the harbor when there’s heavy rain. But perhaps the effort made by restaurants and the Billion Oyster Project may one day ensure the waters around Manhattan and along the East Coast become clean enough to help feed city diners again, hopes Seigal: “I see a future where eventually oysters are farmed for consumption closer to New York City.”

Correction, Nov. 28

The original version of this story misstated the number of restoration sites and number of pounds of shells collected by the Billion Oyster Project. There are 18 and 2 million, respectively, not 15 and 20 million.

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