successful GREEN

Saving the world one oyster at a time

Oysters are more than a tasty, nutritious food. They’re also a key tool in cleaning ocean water, preventing erosion and rebuilding ravaged ecosystems. John Dyer reports from Boston.

Image credit: Charlotte Coneybeer via Unsplash

In the 19th century, oysters were common fare on the tables of aristocrats and industrialists in Britain.

But lately the shellfish has enjoyed a boom among regular diners in London.

From luxury item to standard fare

“We started to change the perception of oysters being a luxury item for the few and to get everyone eating oysters,” Robin Hancock, co-founder of the Wright Brothers restaurant chain, said in an interview with the Independent newspaper.

“We now supply over five tons of oysters a week to the London market and the popularity is growing by 10 per cent year on year.”

Foodies around the world agree. National Oyster Days are now common in the US, Europe and beyond. People eat almost two billion pounds of the bivalve mollusks annually, according to the American organizers of National Oyster Day.

Sustainable solution

But oysters are more than a tasty, nutritious food. They’re also a key tool in cleaning ocean water, preventing erosion and rebuilding ravaged ecosystems. Easy to grow and cultivate, they are a sustainable solution to many of the environmental challenges facing the planet today.

“Over on the mainland you’ve got copper, you’ve got uranium, you’ve got bauxite, but out here, in the ocean, you’ve got oysters – that’s our gold mine,” said Bunug Galaminda, an aboriginal leader in Australia’s Northern Territory, where his community is growing an oyster farm that they hope will provide food and local jobs, speaking to the Australian Broadcasting Corporation.

Adult oysters filter up to 2.5 gallons of ocean water per hour, or as much as 50 gallons per day, eliminating red tide and other waterborne plagues. In healthy waters, oyster reefs provide habitat for crabs, fish, shrimp and other creatures. They also serve as natural breakwaters, absorbing waves and protecting marshes that are key habitats for birds and other animals along the shoreline.

And, of course, some oysters can produce pearls, making their lucrative potential even further.

Easy to cultivate

Growing pearls in oysters is not so easy. But oysters in general are easy to cultivate.

Chop up an oyster and throw it into the rocks and tide pools along the shore. The shellfish might grow easily. Recycle used oyster shells – from restaurants, for example – and throw them and a handful of healthy oysters with them, and the healthy oysters will release larvae that want to stick and grow on the empty shells.

“The definition of sustainability is you harvest the oyster, then you recycle the shell and then the shell gets put back out there to grow new oysters,” said South Carolina Department of Natural Resources Biologist Trent Austin, speaking to USA Today.

They can grow to enormous sizes.

Recently, a construction worker found an 8.5-inch oyster under a pier in New York City, hardly an environment where one would think wildlife would thrive. It weighed 1.3 pounds 610 grams, said the River Project, an environmental group that is helping track the cleanup of the Hudson River.

Heavy rains, dams pose threat

Ironically, the trends that have created the need for sustainable measures, like promoting the consumption and re-growing oysters, are also a threat to the shellfish.

In July, heavy rains in Japan dumped soil into the Kurosegawa River in the Hiroshima Prefecture, the heart of the country’s massive oyster industry. Around a third of the 60 companies in the region reported major losses as the runoff polluted their aquafarms.

In Mississippi, oyster farmers and environmentalists are sounding alarms about a dam project that would divert the flow of freshwater into the Gulf of Mexico to control flooding. The dam would alter the water’s chemical composition and hurt the shellfish.

Oysters need help from humans, in other words, if humans want their help.