“Naked Clams” Could Be the Eco-Friendly Seafood of the Future

Naked clams are bivalve mollusks that, unsurprisingly, look much like clams without a shell – and they could be coming to a menu near you.

These saltwater clams are the eco-friendly, sustainable grub of the future, according to a new study published in Sustainable Agriculture. They feed off rotting wood (thereby recycling waste), can grow 10 times as fast as commercial mussels and, reportedly, taste just as good as oysters.

Cooking shipworms

Naked clams, scientifically known as Teredinidae, are notorious for devouring wooden ships and shipwrecks, which is why they’re more commonly known as “shipworms”.

“Naked clams were previously regarded as a pest in the 1400s and 1500s, due to their tendency to eat wooden ships,” Dr. David Willer, a zoology researcher at the University of Cambridge and lead author of the new paper, told Technology Networks. “They were responsible for stranding Columbus in the Caribbean, changing the course of history.”

“As more modern materials were used for ships, Naked Clams became a non-issue, and were slowly forgotten,” Willer explained.

They were not forgotten in parts of Southeast Asia, however. In this part of the world, the clams are better known as a delicacy, not a pest. In the Philippines, they’re harvested from mangroves and served raw (after being marinated in vinegar, chili peppers and onions) at celebrations.

Willer and his colleagues say there’s a lot to be learned from this Filipino staple; the seafood is high in protein and vitamin B12 and low in fat, feeds off rotting wood that would otherwise go to a landfill and, according to Willer, tastes delicious: “Naked Clams taste like oysters – so very pleasant,” he said.

Mass production of the clams, however, may have its issues. Outside of Southeast Asia, no country has a formalized method of rearing naked clams, and few others have an abundant supply of mangroves to raise the creatures on. Bivalve farming in the west also has several limitations to overcome, including habitat degradation and historical over-exploitation, and the market is hardly booming; retail and consumer interest in mussels and oysters is far weaker than the demand seen in fish and crustacean aquaculture sectors.

Yet Willer and his colleagues still think naked clams have a future in western cuisine, they just need a marketing boost and a proven method of production. The former may take some work, but Willer and his colleagues say they’ve devised the latter.

Farming sustainable clams

In their study, published in Sustainable Agriculture, the Cambridge and Plymouth University research team tested whether naked clams could successfully be reared on wooden planks submerged in static water. To see if the clams’ nutritional content could be boosted with an additional food resource, the team divided the wooden planks into separate containers and gave some of the clams one of two different feeds.

By measuring the clams’ fecal output, the researchers deduced that those fed on wood and an algal formulation absorbed more nutrients, such as omega-3 fatty acid and polyunsaturated fats, than the clams fed on wood and a shellfish blend and those only fed on wood.

Willer and his colleagues claim the nutritional experiment is the first of its kind. Their conclusion: that clams fed on wood and algae offer the best nutritional benefits to prospective diners.

Other feeds may offer even more nourishment, though, and so the team’s work continues.

The Cambridge and Plymouth researchers are trialing different types of waste wood and algal feed in their system to see if they can further optimize the growth, taste and nutritional profile of the clams. They’ve also partnered with Cambridge Enterprise – the commercialization arm of Cambridge University – in the hopes of scaling up their aquaculture system.

“There is an opportunity here to build a completely new aquaculture sector and open up a wealth of avenues for sustainable food,” the researchers write in their study’s conclusion.

Reference: Willer DF, Shipway JR, Aldridge D, Mehrshahi P, Smith A, Strachan A, Lancaster M, Archer L, Papadopoulos K. Naked Clams to open a new sector in sustainable nutritious food production. Sustain. Agric. doi: 10.1038/s44264-023-00004-y

Dr. David Willer was speaking to Leo Bear-McGuinness, Science Writer and Editor for Technology Networks.