Can an Oyster Clean New York Harbor?

Hi, my name is Berrin. I am a young wildlife ambassador, and I studied oysters.

When I first thought about oysters, I mostly thought about their shells.

Then I learned something surprising.

An oyster can spend almost its entire adult life sitting in one place...

and still do an incredible amount of work.

It can filter water, create habitat for other animals, and even help protect shorelines.

That made me wonder:

Could oysters actually help New York Harbor?

Meet the Eastern Oyster

The oyster that naturally lives around New York is called the Eastern Oyster.

Oysters begin their lives as tiny swimming larvae. Eventually, they find something hard—often another oyster shell—and attach themselves to it.

Then they stay there and grow.

More oysters attach.

Then more.

After a while, shell grows upon shell and an oyster reef begins to form.

It is almost like an underwater apartment building.

And oysters are not the only animals living there.

Small fish, crabs, mussels, barnacles, sea anemones, and many other animals can use oyster reefs for shelter and food. NOAA says oyster reefs can provide habitat for hundreds of species.

So when we restore oysters, we are not only helping oysters.

We may be rebuilding a neighborhood.

Wait... Oysters Clean Water?

Yes!

Oysters are filter feeders.

They pull water across their gills and remove tiny algae and particles as they eat.

Under the right conditions, one adult oyster can filter up to 50 gallons of water in a single day.

Fifty gallons!

Imagine fifty one-gallon milk jugs lined up on the floor.

That is a lot of water for one animal that does not even have arms or legs.

But there is something important to understand.

Oysters are not little water-treatment machines that magically remove every kind of pollution. Their filtering can remove algae and particles and improve water quality, but keeping our waterways healthy also requires people to reduce sewage, trash, chemicals, and polluted runoff in the first place.

The oysters can help us.

But we have to help them too.

New York Was Once an Oyster City

This part of the story surprised me the most.

When Henry Hudson arrived in New York Harbor in 1609, NOAA says the harbor's oyster reefs were the largest source of oysters in the world.

Oysters were everywhere.

New York Harbor had huge reef systems, and oysters were an important part of the city's food, economy, and environment.

Then things changed.

For generations, people harvested enormous numbers of oysters. Reef structures were damaged. The city grew. Pollution entered the harbor. Wetlands and shorelines changed.

Overharvesting was one of the main causes of oyster decline in New York, and today pollution, disease, and lack of habitat still make it difficult for wild oyster populations to recover.

New York State says oysters were once very abundant around Long Island and the Hudson-Raritan Estuary, but today only a few small naturally occurring populations remain in some of these areas.

That is a huge change.

So How Many Oysters Are in New York Harbor Today?

This is actually harder to answer than I expected.

There is not one simple number for every wild oyster living in New York Harbor.

Scientists monitor different reefs, restoration sites, and natural populations separately.

But we do know something exciting:

People are putting oysters back.

Billion Oyster Project, a New York City organization working to restore oyster reefs, reports that it has now restored more than 183 million oysters across nearly 18 acres of reef in New York Harbor.

Their bigger goal is to restore one billion oysters and involve one million students by 2030.

Did you notice something?

Students are part of the plan.

Not just scientists.

Not just adults.

Students.

I really like that.

Oysters Are Coming Back to Brooklyn Too

Oyster restoration is happening around New York Harbor, including Brooklyn.

In 2026, plans were submitted for an oyster habitat research project near Bush Terminal Park in Brooklyn. The project would test oyster and reef structures across a 1.3-acre area and help scientists learn how larger restoration projects might work in New York Harbor.

That means this is not only a story about what happened hundreds of years ago.

It is happening right now.

In our city.

Near our neighborhoods.

Under water that many of us pass without even thinking about what is living beneath it.

Why Does an Oyster Reef Matter?

Imagine dropping one oyster shell on the bottom of the harbor.

Not very impressive.

Now imagine thousands and thousands of oysters growing together.

Suddenly there are cracks, holes, bumps, tunnels, and hiding places.

Small animals move in.

Fish come looking for food.

Young crabs find places to hide from predators.

The reef becomes an ecosystem.

Oyster reefs can also help slow waves and reduce erosion in some locations, which can help protect shorelines and wetlands.

So an oyster reef can do at least three amazing things:

Filter water. Create homes. Help protect shorelines.

That is a lot of work for an animal that barely moves.

How Do You Build an Oyster Reef?

Here is another strange fact:

To bring oysters back, sometimes you need...

old oyster shells!

Baby oysters need hard surfaces to attach to. Old oyster shells are excellent places for them to grow.

Billion Oyster Project collects used shells from New York City restaurants instead of letting them go into the garbage. According to the organization, more than 3.2 million pounds of oyster shell have already been recycled through partnerships with more than 75 restaurants.

Those shells can become the beginning of new reefs.

Think about that journey:

Restaurant → shell recycling → baby oysters → oyster reef → fish habitat.

Something that looked like garbage becomes part of a living ecosystem again.

Can We Eat the Oysters in New York Harbor?

No.

The oysters being restored in New York Harbor are there to help the ecosystem, not to become somebody's dinner.

Water-quality problems, including sewage contamination, mean oysters from New York Harbor should not be eaten. New York State carefully tests shellfish-growing waters and closes areas that do not meet health standards for harvesting.

So if you see oysters growing in the harbor:

Leave them there.

They have work to do.

What Can Kids Do?

You might be thinking:

“Okay... but I am not going to build an oyster reef tomorrow.”

Probably not.

But kids can still help.

• Keep plastic, bottles, and other trash out of waterways.

• Join a shoreline cleanup.

• Never throw fishing line or other waste into the water.

• Learn where storm drains lead and help keep trash away from them.

• Visit a waterfront and observe what is living there.

• Learn about oyster restoration projects in New York City.

• Recycle oyster shells through participating programs instead of throwing them away.

• Make art, posters, videos, or writing that teach other people why oysters matter.

• Tell someone that New York Harbor is not just water between buildings—it is a living ecosystem.

And maybe one day, you can even volunteer on an oyster restoration project.

Students are already helping scientists monitor oysters, collect data, and study New York Harbor. Billion Oyster Project says more than 66,000 students have participated in its programs so far.

Maybe we could be some of the next ones.

What Oysters Taught Me

Before studying oysters, I thought protecting wildlife meant protecting animals that move around.

Birds.

Butterflies.

Fish.

But an oyster taught me something different.

An animal does not have to fly across the world like a sandpiper.

It does not have to migrate like a Monarch.

It does not have to swim in giant schools like menhaden.

An oyster can stay almost completely still...

and change the world around it.

As it filters water, another animal may benefit.

As a reef grows, a young fish may find a hiding place.

As thousands of oysters grow together, a shoreline may become a little stronger.

That made me think differently about what it means for something to be important.

Sometimes the animals we hardly notice are quietly holding an ecosystem together.

So the next time you stand beside New York Harbor, look at the water and imagine what might be happening underneath.

Millions of tiny living things are working down there.

And some of them are oysters.

Maybe helping New York Harbor come back begins by giving those small lives a place to grow again.