Photo: Von Wong

Manhattan was once home to an incredibly rich marine environment. These student scientists are working to bring it back

What do you think of when you hear the words “New York Harbor”? Sewage? Pollution? Hulking container ships and the occasional body sent to sleep with the fishes? Are there even “fishes” anymore?

For students at the New York Harbor School, a public marine science and technology high school in the center of the harbor on Governor’s Island, they think of aquaculture, coastal piloting, professional scuba diving and oysters. Specifically, the one billion oysters they’re aiming to grow by 2035 to help restore the once-rich marine ecosystem where the Atlantic Ocean meets Long Island Sound, the Hudson River and Raritan Bay.

The Harbor School is the birthplace of the Billion Oyster Project, an ambitious plan to heal the troubled waters of New York Harbor by growing and restoring one billion of the powerful bivalves. While most New Yorkers rarely spare a thought for the harbor, BOP is partnering with schools and restaurants to rewild a marine environment in one of the biggest cities in the country. Sound badass? We think so, and we turned to Harbor School and Billion Oyster Project creator Murray Fisher to learn more. Here’s what you need to know:

Students at New York Harbor School are involved in every aspect of BOP, including underwater monitoring of oyster grow sites. Von Wong

New York Harbor was once amazing.

Manhattan had trout.

“This entire Hudson-Raritan Estuary was teeming with fish and teeming with wildlife and birds,” Fisher says. In fact, one of the original Dutch settlers at what was dubbed New Amsterdam wrote that fishing was as easy as lowering a basket beneath the surface. “There were so many fish that they couldn’t get out of the way of a moving basket in the water,” Fisher says.

That historical abundance also applied to the native oysters. “New York Harbor was the oyster capital of the world,” Fisher explains, describing 220,000 acres of oyster reefs in the region that served as a crucial source of food, filtered the water and buffered against storm swells.

“What we imagined was here and what we have heard was here is one of the most biologically productive places on the planet that sustained human life for about 8,000 years. The last 400 years we have wiped out almost all of the other animals we once lived with.”


We screwed it up.

“The worst point was probably the early 1900s,” Fisher says of the harbor’s health.

By then Manhattan was supporting a lot more people, and they were using a lot more water— water that returned to the harbor carrying nastiness like raw sewage and industrial waste. Once-pristine oysters now carried typhoid and the fish populations plummeted.

“The water was so disgusting everywhere in New York City for 50 years that—from the early 1900s until the Clean Water Act was passed in 1972—the water was a thing to be avoided,” Fisher says. “All of the [housing] projects were built on the water.” The island’s best neighborhoods were the farthest from shore.

After the passage of the Clean Water Act, pollution in New York Harbor has improved dramatically, but it’s still a far cry from the vibrant, biodiverse environment of its natural state.

A billion oysters could hypothetically filter all the water in New York Harbor every three days. Von Wong

A billion oysters can help.

“What’s unique about them is that they’re called ecosystem engineers,” Fisher says. “Oysters play the same role as coral, where they aggregate into these big reefs that provide habitat, hiding and places to reproduce for these other animals.”

Oysters are also filter feeders. Like tiny marine vacuums, they devour suspended solids in the water, making the harbor clearer and cleaner. And they remove nutrients like nitrogen, which can cause algae blooms and low oxygen levels.

Scientific estimates place the standing volume of New York Harbor at 74 billion gallons, and a single adult oyster can filter at least a gallon of water each hour. So with a billion oysters, the entire volume of the harbor could be filtered every three days, Fisher says.

Finally, oyster reefs also perform “ecosystem services,” slowing waves and diminishing the power of storm surges like the ones that devastated the region during Hurricane Sandy. Healthy oyster reefs wouldn’t have changed the height of the water, but they would have served as wave breaks, muting the force of the heavy surge.


Kids make great environmental scientists.

For Billion Oyster Project, Fisher says, the mollusks’ most important function is how they connect local kids with the environment.

Harbor School students are involved in every step of the process to grow a billion oysters by 2035, from welding oyster cages and tracking growth to gathering data from reef sites by scuba diving and piloting underwater drones.

BOP also works with other middle and high schools to install oyster restoration stations around the harbor. Students do most of the work themselves, visiting regularly to collect data for BOP, measuring the oysters’ progress and impact, and conducting their own hands-on field research projects.

“What we have found is that [the oysters are] most valuable because they’re a pretty compelling and pretty easy way to engage young people in their marine environment,” Fisher says. “These kinds of experiences are transformative and increasingly rare for kids.”

For students growing up poor in dense urban centers, even more so. “Kids who can’t afford to leave their neighborhoods very much are the ones that have the fewest connections to those transformative experiences in the natural world. At its core, that’s what we’re trying to address.”

Since officially launching Billion Oyster Project in 2014, the group has already worked with 65 schools and around 3,000 students to grow 25 million oysters.

“We want New York Harbor to be a highly functional ecosystem that’s easily and readily accessible to every kid, and that becomes well known and well loved by young people in all of New York City,” Fisher says.

If you squint, you can almost see a healthy harbor cared for by a new generation of environmental custodians—with a billion oysters hard at work beneath the surface.

To learn more about Billion Oyster Project, visit

Photos by: Von Wong. To see more images of New York Harbor School, visit