Shipworms, or "naked clams", growing in a wood panel.
Photo: University of Cambridge.
"Naked clams" grown in waste wood: a new source of seafood?
They are the world's fastest-growing bivalve mollusc, able to reach 30cm long in only six months - but you may know Teredinids better as "shipworms".
Commonly considered a marine pest, in former days they were a significant problem for sea-going industries, boring their way through wooden ships, quays and other marine structures.
However, now these wood-eating bivalves - a shell-less relation of oysters and mussels - may have a role to play in sustainably-produced human nutrition.
In the UK, a team of researchers from the Universities of Cambridge and Plymouth have been working on just that, devloping the world's first system for farming shipworms - and they've given the creatures a somewhat more appetising rebrand, calling them "Naked Clams".
A fully-enclosed modular aquaculture system for farming "naked clams"
To cultivate the bivalves, the research team developed a fully-enclosed aquaculture system that can be completely controlled, eliminating the water quality and food safety concerns often associated with mussel and oyster farming.
The system's modular design means it can be used in urban settings, far from the sea, the researcher team says.
Highly nutritious "naked clams" reach harvestable size faster than other species
The researchers found that the levels of Vitamin B12 in the Naked Clams were higher than in most other bivalves – and almost twice the amount found in blue mussels. And, when an algae-based feed was added to the system, the Naked Clams could also be fortified with omega-3 polyunsaturated fatty acids.
“Naked Clams taste like oysters, they’re highly nutritious and they can be produced with a really low impact on the environment,” said Dr David Willer, Henslow Research Fellow at the University of Cambridge’s Department of Zoology and first author of the report.
Growing without a shell also has its advantages: the naked clams save on energy, and grow much faster than mussels and oysters which can take two years to reach a harvestable size, the researchers explained.
Juvenile "naked clams" in a petri dish.
Photo: University of Cambridge.
Naked Clams could be a source of nutritious and sustainable protein for processed foods, say researchers
Shipworms are already eaten in the Philippines - either raw, or battered and fried like calamari, the research team notes. However, for the UK market, the researchers suggest that Naked Clams could be more popular as a "white meat" substitute in processed foods such as fish fingers and fishcakes.
“We urgently need alternative food sources that provide the micronutrient-rich profile of meat and fish but without the environmental cost, and our system offers a sustainable solution,” said Dr Reuben Shipway at the University of Plymouth’s School of Biological & Marine Sciences, senior author of the report.
Dr Shipway (left) and Dr Willer (right), the researchers developing "naked clam" aquaculture.
Photo: University of Cambridge and University of Plymouth.
Research group aims to commercialise the system
The team is now trialling different types of waste wood and algal feed in their system to optimise the growth, taste and nutritional profile of the Naked Clams – and is working with Cambridge Enterprise to scale-up and commercialise the system.
The research is a collaboration between the Universities of Cambridge and Plymouth, and has attracted funding from sources including The Fishmongers’ Company, British Ecological Society, Cambridge Philosophical Society, Seale-Hayne Trust, and BBSRC. The full research report was published in the journal Sustainable Agriculture.
