King of the clams: a quick guide to geoducks
In Asia, geoducks or "elephant clams" are an established delicacy and each sell for up to $300 each. There is a high demand for Geoduck worldwide, but only a small handful of countries have a Geoduck aquaculture industry.
Purportedly an aphrodisiac, the texture of the geoduck is likened to a combination of clam and chicken, with the meat tasting like a sweeter version of crab.
Traditionally, the neck is cut or ground and used in chowders or sautéed. Sushi fans may also have tasted the delicacy in their sashimi without knowing it – geoducks are known as mirugai in Japanese.
- AUT University is working with Aquaculture NZ to meet the $1 billion sector goal by 2025. Following several feasibility studies, Geoducks (also known as King Clams) were identified as one of two primary shellfish species to develop for export potential due to their high market worth.
AUT’s Aquaculture Biotechnology Group (headed by Assoc Prof Andrea Alfaro) recently partnered with Cawthron Institute to develop Geoducks for export.
- Geoducks currently sell for up to $40/kg. Compare that to $2/kg for green lipped mussels (keeping in mind green-lipped mussels represent NZ's largest shellfish industry at $200M per year in exports) and you can see the potential ecomomic benefits for the Geoduck.
When you’re a geoduck (pronounced “gooey duck”, scientific name panopea zelandica), appearances can be deceiving in more ways than one.
Found in New Zealand waters, it is the largest burrowing saltwater clam in the world. With an average weight of approximately one kilogram and an average shell size of 20 cm, the geoduck has, understandably, earnt the name of ‘king clam’.
Based on its phallic appearance, the name of ‘elephant-trunk clam’ is another obvious name.
“Geoducks are an established delicacy overseas,” says Associate Professor Andrea Alfaro, who heads AUT’s Aquaculture Biotechnology Group.
“Due to a robust demand from Asia and North America for geoduck, the capture fishery cannot satisfy the demand in an ecologically sustainable fashion. On a return-per-acre basis geoducks are the western region’s most valuable cultured shellfish species. Hence the intense interest in geoduck aquaculture and the predictions for continued rapid growth.”
In partnership with the Cawthron Institute, new research at AUT is now underway investigating the aquaculture market potential for geoducks in New Zealand and overseas.
The institute is known for its leading research and development of New Zealand’s seafood industry and sustainable management of the coastal and freshwater environment.
Mostly found off the Pacific coast of the United States and Canada, geoduck aquaculture does not exist in New Zealand as yet, says Alfaro, although they are harvested by scuba divers in the South Island’s Golden Bay at depths of about 18 metres.
“Recent trials at Cawthron Institute in Nelson have resulted in successful production of panopea zelandica seed [juveniles], which will soon be transplanted to wild growing areas,” says Alfaro. “If New Zealand geoduck can be successfully cultivated to market size, this species will bring an added value to the growing aquaculture industry in this country.”
Doctoral student Le Viet Dung, who previously investigated the cultivation of a smaller geoduck species in Vietnam, is working alongside Alfaro conducting this research.
“Le’s previous knowledge will make a vital contribution to the cultivation of our New Zealand species. It is envisioned that this government-funded research will generate the biological knowledge to successfully cultivate panopea zelandica to market size,” says Alfaro.
“Since there is a high demand for geoduck worldwide and only a few countries have a geoduck aquaculture industry, it is anticipated that New Zealand can easily break into this international market.”
In 2005 about 47.5 per cent of the geoduck market (panopea generosa market) came from British Columbia in Canada, another 47.5 per cent came from Washington, USA and five per cent from Alaska. The geoduck production in British Columbia alone was around 2 million tonnes a year during 2006-2008 and the price was also steady at US$20/kg, yielding US$40 million per year.
“The large meaty geoduck siphon is prized for its savoury flavour and crunchy texture. In Asia especially it’s a real delicacy, each costing up to $300, so you can see the potential market value,” says Alfaro.
Purportedly an aphrodisiac, the texture of the geoduck is likened to a combination of clam and chicken, with the meat tasting like a sweeter version of crab. Traditionally, the neck is cut or ground and used in chowders or sautéed. Sushi fans may also have tasted the delicacy in their sashimi without knowing it – geoducks are known as mirugai in Japanese.