Howth Yacht Club, the Royal St George Yacht Club and The National Yacht Club in Dún Laoghaire have agreed to host a number of “oyster gardens” which will be suspended from their marina pontoons.
This follows the success of similar shellfish “gardens” installed at Dún Laoghaire, Malahide and Poolbeg marinas earlier this year.
Oysters were once fast food for Dubliners in the early 1800s
Oysters were once “fast food” for Dubliners in the early 1800s. Shellfish sellers back then were the equivalent of today’s coffee shop owners, according to diver, sailor and coffee maker David Lawlor.
Oysters are also “climate champions” because of their natural habit of filtering water, and this helps to reduce excess nutrients and pollutants, Mr Lawlor says.
He set up the Green Ocean oyster reintroduction project as a philanthropic enterprise a year ago with the aim of restoring native oysters, like the European flat oyster, throughout Dublin Bay.
When Mr Lawlor and his partner Marguerite learned to dive 20 years ago in Scotsman’s Bay off Sandycove, south Dublin, he remembers being struck by the lack of life on the seabed.
“That’s not the way it was 500 years ago and it has stayed with me ever since,” he says.
He began the project by taking oysters from Tralee Bay in Co Kerry, with the approval of the Marine Institute, and filling some 60 baskets of them to install at the first three marinas.
The oyster gardens encourage the growth of seagrass and seaweed, providing vital spawning grounds for fish
Enlisting the support of three more yacht clubs this autumn has allowed him to expand from 60 baskets to 120 baskets, cultivating 900 native oysters in all.
“We had mortality rates of less than 3pc with the first phase, which compares very favourably with similar projects in Britain,” Mr Lawlor says.
The oyster gardens have an added benefit as they encourage the growth of seagrass and seaweed, providing vital spawning grounds for fish and contributing to sequestering atmospheric carbon, he says. “Once the oyster beds take hold and begin to form reefs, they will allow for a stable habitat which can also provide a natural barrier to coastal erosion,” he adds.
Mr Lawlor estimates that the 120 oyster gardens will filter about 1.3 billion litres of water annually, removing nitrates and algae.
David Lawlor hopes the project will improve water quality and enhance marine biodiversity in Dublin Bay. Photo: Michael Chester
Students from University College Dublin and Trinity College Dublin have been working with him to monitor the oyster restoration locations and to track biodiversity improvements.
Mr Lawlor has incorporated the project as the not-for-profit Green Ocean Foundation and has engaged volunteers on maintaining the oyster baskets and monitoring shellfish health. “Our goal is to establish a self-sustaining broodstock of native oysters in Dublin Bay,” he says, explaining that it is a 15 to 20-year plan.
He hopes to involve schools, colleges, businesses and members of the public who will in turn raise awareness about how the marine environment can help to combat the negative impact of climate change.
As there is no commercial aspect to the cultivation, no foreshore licenses are required, he says. However, he did conduct extensive consultation with state agencies, including the National Parks and Wildlife Service.
