Oysters placed into safe harbors in effort to replenish their numbers

On a recent Sunday, a group of volunteers set off into Oyster Bay Harbor on a 26-foot vessel loaded with a few dozen oyster-filled cages.

The oysters were tiny at the start of the summer — smaller than the size of a fingernail. Every couple of weeks, volunteers came to the sandy shores of Beekman Beach in Oyster Bay to maintain them. They cleaned their cages of sea squirts and other harmful critters that inhibit shellfish growth.

A few weeks ago, the volunteer group sent the mollusks — by then, grown to about an inch and a half wide — over the boat into a protected area in Oyster Bay Cove.

By descending to the bay bottom, the shellfish should have the best chance to survive and form clumps of oyster reefs. Those efforts should help replenish the dwindling population of filter feeders.

“It’s like sending them off to college,” said Michele Pasqualina, 48, of Oyster Bay. She is one of the volunteers with the Oyster Bay/Cold Spring Harbor Protection Committee's oyster gardening program, which is spearheading the initiative.

The annual oyster gardening program is among several efforts to stabilize and improve shellfish numbers in Oyster Bay and Cold Spring harbors, once a bountiful source of shellfish but whose populations have declined, according to state data. The trend has mirrored data up and down the East Coast. In Oyster Bay, town officials have set aside more underwater acres to preserve shellfishing while opening up new areas for public harvesting.

Pasqualina, who joined the oyster gardening program in 2021, said growing oysters starts in early summer, when the volunteer group receives a batch of seedlings from Cornell Cooperative Extension.

“The babies come in and we have to distribute them to all the beaches,” said Pasqualina. 

After oysters are dispersed to multiple spots, risks and dangers persist. Volunteers help them fend off parasites, predators and other pesky problems on their journey, like the sea squirt, which latches onto the cages and can prevent oysters from growing.

“There’s new challenges every year,” Pasqualina said.

Claudia Kulhanek-Pereira, 43, of Locust Valley, was part of the group that set out to place the oysters in their new habitat. The group used her family’s boat to help transport the shellfish this year to areas suitable for shellfish growth.

Adelphi and Stony Brook universities conducted studies examining oyster settlement patterns, water flow and other factors that can affect the success of oyster spawns. 

“It’s wonderful that as you see this program grow, now there’s other sanctuary spots,” Kulhanek-Pereira said.

Rob Crafa, the committee's coordinator, said this year’s oyster gardening program produced between 30,000 and 50,000 oysters. He said the program recently has begun growing oysters on “spat-on shells,” meaning the baby organism is set on a recycled adult oyster shell.

That approach encourages oysters to clump together on the bay bottom, creating habitat and more opportunity for oyster spawn to grow, he said.

The oysters in the program are frequently monitored and measured, Crafa said, leading to most of them surviving the summer months. Usually, mortality rates are below 5%, he said.

However, this year he said about 5% to 10% of the oysters died, “which, in nature would be nothing, but for what we do, it’s a little interesting.”

He said the causes of higher die-off rates, which have been observed by other researchers in different locations, is not yet clear. Still, Crafa said the efforts to replenish the population in Oyster Bay are bearing slow signs of progress, including natural growth of population clusters.

“It’s taken us a while, but we’re moving in the right direction,” Crafa said.

Christine Suter, executive director of the nonprofit Friends of the Bay, said the gardening program is particularly effective.

“You can do lectures, and you can write articles about conservation and teach people about how to get involved with environmental stewardship, but having a hands-on program like oyster gardening is really important because people really get involved and invested in the outcome of these oysters,” Suter said.

By Joseph Ostapiuk

joseph.ostapiuk@newsday.com@OstapiukJ