Sea urchin ranching to be expanded to semi-commercial scale

Published on
November 29, 2019

Sea urchin ranching innovator Urchinomics is establishing a semi-commercial scale feeding facility in Japan’s Oita Prefecture.

The concept behind the farm is to harvest empty sea urchins from areas where kelp beds have been overeaten, and feed them in a land-based facility until they grow to marketable size. When sea urchins overgraze kelp beds, they eat themselves out of their food source. But rather than die from starvation, they can survive for long periods with little or no food, though the contents of their spiny shells are reduced, making them unmarketable as uni.

The company got its start when Norwegian investment firm Kaston AS obtained the rights to a sea urchin feed formulation developed at Norway’s Nofima Food Research Institute and spun off Urchinomics into a separate company. Urchinomics now has several group companies in Tokyo, Japan; Halifax, Canada; Ijmuiden, the Netherlands; and Ulsteinvik, Norway.

Brian Tsuyoshi Takeda, who spearheaded the effort to create the feed at Kaston, is now the CEO of Urchinomics. The feed is produced by Yokohama-based feed company Nosan, a fully-owned subsidiary of Tokyo-based Mitsubishi Corporation, using ingredients that are a byproduct of kelp harvested for human consumption.

Urchinomics Business Developer for Japan Yuma Yamamoto said the company was expecting to start operations in Oita around the end of this year. He said a shipping container with raceways and filtration equipment is now on its way from the Netherlands.

The company will start with just 18 raceways. It takes two months to feed up the urchins, so the plan is to run six cycles per year resulting in 720 kilograms each, for a total annual production of 4,300 kilograms. This weight includes the shell, so the edible portion is much less.

According to a research paper, the maximum edible yield from sea urchins is 20 percent, so that would put the short-term production of edible uni at about 860 kilograms. In three years, they plan to have 200 raceways, each five meters in length, which would produce 45 metric tons (MT), or up to nine MT of edible uni.

This project uses a recirculated aquaculture system (RAS), and thus requires a filtration system. Yamamoto said the choice of whether to use an RAS system or a flow-through system depends on the conditions at each site.

Prior to the present site, test production was tried in two Japanese locations. The original location was in Miyagi Prefecture, where kelp beds had been damaged by the earthquake and tsunami. Then, sea urchins grown in Aomori Prefecture were test marketed in Tokyo at a sushi restaurant in the fashionable Ginza district called Nemuro Hanamaru Ginza. They have a processing partner that prepares whole urchins in packs of two, with a hole cut for scooping out the roe – the urchin equivalent of oyster on the half-shell.

Yamamoto said that because Japanese fisheries law gives priority access to local fishery cooperatives, Urchinomics is seeking fishery cooperative partners for a joint venture.

“The challenge is finding ranching partners in Japan,” he said.

In other countries, some progress is also being made. The company has signed a letter of intent to set up an RAS operation in California's Bodega Bay on a 500,000-square-foot property. Urchin barrens, which are desert-like sea areas completely denuded of vegetation by an excess of urchins, are widespread in the area. This is partly due to water temperature changes and partly due to a disease that decimated sunflower stars, which feed on urchins. However, the overpopulation mainly consists of purple sea urchins (Strongylocentrotus purpuratus) rather than the larger and more highly valued red sea urchin (Mesocentrotus franciscanus).

Another potential site is in Newfoundland, where the company has worked with Memorial University associate professor Patrick Gagnon, Green Seafoods, and Quebec-based Pêcheries Shipek SEC. The green sea urchin (Strongylocentrotus droebachiensis) is the target species here.

Although the idea of removing sea urchins to allow regrowth of kelp goes beyond sustainability to be “restorative,” Yamamoto said that the “ranching” model is not suitable for Aquaculture Stewardship Council (ASC) certification, as they use the wild resource.

Although the company’s website focuses on the environmental aspect rather than on selling uni, Urchinomics is not looking for government subsidies for environmental remediation, though it does need to obtain the right to collect a resource that others may also want. The PR focus on the environment is rather intended to attract international eco-investors, according to Urchinomics. 

Photo courtesy of Urchinomics    

Contributing Editor reporting from Osaka, Japan

Want seafood news sent to your inbox?

You may unsubscribe from our mailing list at any time. Diversified Communications | 121 Free Street, Portland, ME 04101 | +1 207-842-5500