Project aims to grow sea urchins in land-locked prefecture

The Yomiuri Shimbun

7:00 JST, December 21, 2022

KUKI, Saitama — In land-locked Saitama Prefecture, a project will soon be underway to to cultivate a delicacy of the ocean, sea urchins.

The enterprise in the city of Kuki will use artificial seawater made from the waters of a local hot spring, which will then be recirculated as it is purified. There is also an idea to use local vegetables and fruits as feed as a way to further promote the locally produced sea urchins.

The goal is to have the aquaculture farm ready by March of next year, with the cultivating of sea urchins beginning in September for shipment in November.

Teaming up on the project, which was announced at a press conference on Dec. 15, are Yamatake, which manages the Mori no Seseragi Nagomi hot spring facility, and the National Institute of Technology, Ichinoseki College, located in Ichinoseki, Iwate Prefecture, which has water purification technology.

Two 4-ton water tanks are to be installed in a vinyl greenhouse built on farmland adjacent to the hot spring facility. Technology using ozone will be adopted for the purification of the artificial seawater, while the water temperature will be controlled by a heat exchange system with the hot spring water. Feeding will be managed by a device equipped with artificial intelligence.

A special app has been developed to analyze the water quality. Costs to set up the facility are estimated at about ¥50 million, which will be partially funded by business restructuring subsidies from the Economy, Trade and Industry Ministry.

According to Yamatake Executive Director Daigo Yamanaka, a test run that was started last May has resulted in about 50 sea urchins being successfully cultivated in a small tank.

Yamatake intends to bring in sea urchins from a hatchery to be built in Hachinohe, Aomori Prefecture, once the project goes into full operation and with the cooperation of people in the fishery industry.

The company plans to raise 6,000 sea urchins to a size sufficient for shipping at the aquaculture farm in Kuki over a period of about two months.

“First, we want to serve them at the restaurant in the [hot spring] facility,” Yamanaka said. “It would also be good to use vegetables and fruits produced in Kuki as feed.”

Once the project gets off the ground, the company intends to set up hatcheries in other prefectures to ensure a stable supply of sea urchins.

“By cultivating, sea urchins can be shipped even in the off season,” said Takashi Watanabe, an associate professor at National Institute of Technology, Ichinoseki College. “We hope to give a boost to Japan’s fisheries industry as a whole through this technology.”