Cosmopolitan Oysters

by Meg Walburn Viviano

Spat Grow in Baltimore’s Harbor East Marina.

Oyster spat arriving at Harbor East Marina.

Oyster spat arriving at Harbor East Marina.

Baltimore’s upscale Harbor East neighborhood is known for high-end shopping, hotels and five-star restaurants. It has not been known for oyster restoration—until now.

It’s a drizzly fall day when the Chesapeake Bay Foundation (CBF) truck pulls up alongside the Harbor East Marina, where 18,000 baby oysters will get their start. CBF employees proclaim it to be “a perfect day for moving oysters . . . keeps ’em moist!”

With the help of marina volunteers, workers install 25 oyster cages, along the dock just below the popular Baltimore Promenade. Inside the cages are recycled oyster shells, with tiny, lab-grown oyster spat attached.

The goal is to give the oysters a better chance at growing to maturity.  CBF scientists estimate that about 70 percent of the spat survive in the cages, versus only 20 to 40 percent in the wild. With the Bay’s oyster population at less than one percent of historical levels, conservationists are working hard to help them repopulate. Growing in cages and later planted together on top of each other gives oysters the chance to grow communally. It’s known as a “3-D oyster, reef” the Bay’s version of a coral reef. 

Oysters   ready for deposit at Fort Carroll. 

Oysters ready for deposit at Fort Carroll. 

But there’s another reason for raising oysters in the Baltimore harbor—the bivalves are natural filters, and can help clean the water. Fecal bacteria, litter and stormwater runoff continue to plague the harbor. The city’s Healthy Harbor Initiative (HHI), which grades the harbor on pollution annually, has given it a failing grade for the last three years. Its lofty goal is the make the water “swimmable and fishable by 2020.”

That’s why HHI and CBF have teamed up to create “The Great Baltimore Oyster Partnership,” an
effort to bring five million oysters to the Patapsco River over the next five years. In all, 200 cages will be planted at the city’s waterfront, from Canton to Curtis Bay.

The installation at Harbor East, which is taking place right on the Promenade, attracts the attention of tourists and lures curious businessmen outside. The curiosity factor is another reason the partnership is putting oyster cages in areas around the harbor with lots of foot traffic. They want to raise awareness for these conservation efforts. 

For six months, the young oysters grow in their urban home, filtering the water around them. The Chesapeake Bay Foundation and the marina share baby-raising duties, keeping the cages clean and monitoring their temperature through winter.

Come June, the spat are ready to graduate to a protected oyster reef at Fort Carroll, near the Key Bridge in the Patapsco River.

On a Monday morning, a CBF boat arrives at the Harbor East Marina to pick up the oysters, along with employees from the marina and the Healthy Harbor Initiative. They’re now big enough to move to their forever home.

When the cages come out of the water, they are fuzzy with algae, and it’s obvious that more than just oysters have claimed the cages as habitat. One of the CBF employees squeals as she lifts a cage to find an eel squirming around inside. A tiny shrimp, ready to lay its eggs, turns up in another cage. A water snake passes under the dock nearby.

A close-up of the spat attached to recycled oyster shells.

A close-up of the spat attached to recycled oyster shells.

Once the messy job of transferring oysters from cages to buckets is done, the group loads up the Snow Goose, a CBF workboat used mostly for educational trips. During the smooth ride out to Fort Carroll, marina employees and oyster pros count the number of tiny oyster spat alive and attached on the larger recycled shells. Healthy Harbor Initiative’s Carmera Thomas estimates tens of thousands of baby oysters made the trip. Thomas and others marvel over the size of this group of spat: larger than groups from other harbor installations, likely because the Harbor East location is so well protected.

As the Snow Goose cruises into the river, Jocelyn Tuttle, CBF’s Baltimore Harbor Education Program Manager, gives a quick history of oysters at Fort Carroll. Restoration groups have been planting oysters at the site for more than 20 years, since it’s an easy distance from the Baltimore harbor but it’s far enough out that the water is cleaner here. It’s also a relatively shallow spot, around 15 to 16 feet.

Fort Carroll, an abandoned, unfinished military fort with foreboding signs that read, “Keep Off, Guard Dog” gives off a slight horror-movie vibe. Cormorants and seagulls line the walls of the fort, and the smell of wildlife is, in a word, stinky. Tuttle explains that the fort serves as a bird sanctuary, because the oyster reefs attract small organisms and fish that the birds feed on.

CBF employees decide on which side of the island to plant the oysters, and the crew gets to work dumping oyster shells over the side. These are the last of the estimated 409,000 juvenile oysters to be planted at the reef this year. Last year, they planted 111,000. 

This fall, The Great Baltimore Oyster Partnership plans to drop even more cages around the harbor.

Whether the water will be swimmable by 2020 remains to be seen. But at least we’ll know that there are hundreds of thousands of oysters, doing their part to improve the water quality.