Oysters, Planted in Cages at Baltimore Harbor, Graduate to Reef

On Monday morning, the Chesapeake Bay Foundation (CBF) and the Healthy Harbor Initiative moved more than 43,000 oyster spat from the Harbor East Marina to their "forever home" in the Patapsco River.

Chesapeake Bay Magazine was there when the tiny oyster spat, planted on recycled shells, were put in cages and installed at the marina along Baltimore's popular Promenade. That was back in October 2016. Since then, employees from Harbor East Marina and other volunteers have been cleaning and checking on the cages. Cleaning is important because algae builds up on the cages, smothering the oysters and keeping water and oxygen from flowing through.

It's part of a growing program called The Great Baltimore Oyster Partnership. At almost a dozen different locations around Baltimore's harbor, oyster spat are planted and left to mature about six months, until they can be moved to a more natural habitat.

Now, the baby oysters are big enough to move out to the wild, which in this case is a protected oyster reef at Fort Carroll, near the Key Bridge. And Chesapeake Bay Magazine got an exclusive ride out to the reef.

The harbor's oyster program accomplishes three things. One, adding lab-grown oysters helps to rebuild the Bay's population, which has dwindled to just 3 percent of what it once was. Two, while the oysters are living in Baltimore harbor, they serve as natural filters to help clean the water. And three, their shells and cages become habitats for other wildlife.

When the cages came out of the water Monday, they were fuzzy with algae and it was obvious that more than just oysters had claimed them as habitat. One of the CBF employees squealed as she lifted a cage to find an eel squirming around inside. There was also a tiny shrimp, getting ready to lay its eggs, and a water snake that passed under the dock—all in the shadow of the Legg Mason Tower and the Four Seasons Hotel.

Once the messy job of transferring oysters from cages to buckets was done, we loaded up the Snow Goose, a CBF workboat used mostly for educational trips. During the relatively smooth ride out to Fort Carroll, the Harbor East Marina employees and oyster pros counted how many tiny oyster spat were still alive on the larger recycled shells they had attached to. Healthy Harbor Initiative's Carmera Thomas estimates some 43,400 baby oysters made the trip. Thomas and others marveled over the size of this group of spat: larger than usual, likely due to the protected Harbor East location.

As we reached the oyster reef, Jocelyn Tuttle, who is CBF's Baltimore Harbor Education Program Manager, gave me 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 itself gave off a slight horror-movie vibe, an abandoned unfinished military fort with foreboding signs that reads, "KEEP OFF. GUARD DOG." Cormorants and seagulls lined all of the walls of the fort, and while we never actually tied up to the island, the smell of wildlife reminded me of the flamingo enclosure at the zoo—stinky. Tuttle tells me the fort serves as a bird sanctuary, because the oyster reefs attract small organisms and the fish that the birds feed on.

CBF employees decided on which side of the island to plant the oysters, and the crew got to work dumping oyster shells over the side. They were the last of the estimated 409,000 juvenile oysters planted at the reef this year, compared to only 111,000 last year. And this coming fall, The Great Baltimore Oyster Partnership hopes to plant even more spat around the harbor.

Megan Viviano