NAGAOKA/NIIGATA, Japan — Japanese exports of expensive ornamental carp are increasing. Nishikigoi (brocaded carp), also known as koi, are beautiful and graceful, and are considered auspicious fish in Asia. They are increasingly popular in China and elsewhere in the world, and prices sometimes reach millions of yen apiece.
In Niigata Prefecture, koi breeders are using their ingenuity to ensure that the “swimming jewels” are transported safely and efficiently, and a research laboratory is making efforts to develop new technologies to raise the efficiency of transportation of the fish and protect them from disease.
A nishikigoi auction was held in Nagaoka, Niigata Prefecture, in late October. The auction hall was filled with an enthusiastic atmosphere, with 72 buyers from Japan and overseas attending the event. Participants from the U.S., Germany, China, Thailand and Vietnam also joined in bidding large amounts of money for the carp they wanted.
The koi breeding business is supported by strong demand from overseas. “Exports account for 95% of our sales,” said Fujio Oomo, a director at Nishikigoi Niigata Direct, a company in Nagaoka that produces, sells and exports koi. “More than 90% of our sales come from exports, mainly to Asia,” said Futoshi Mano, president of Dainichi Koi Farm, the largest koi breeder in Niigata Prefecture, based in the city of Ojiya.
To avoid trouble with customers and nishikigoi lovers who purchase the fish, koi producers have to transport the fish safely and efficiently by attending to various conditions, including temperature control. Nishikigoi Niigata Direct became the first koi breeder to introduce a dedicated container for exporting nishikigoi. The company developed the transport container, made of expanded polystyrene, jointly with Toho Industries, an Osaka-based styrene foam maker, and logistics giant Nippon Express.
The company used to put koi in corrugated cardboard containers to export them. This method, however, could not be used to export the fish in the hot season, from June to September, because the temperature of water in the container could rise rapidly during transportation, harming the health of the fish. However, the styrene foam container has better heat insulation properties and keeps the water temperature lower, allowing the fish to be exported all year round.
Other countries, including Israel, Thailand and Indonesia, also produce and export nishikigoi, so koi producers need to reduce transportation costs to compete. The styrene foam container costs more than the conventional corrugated cardboard container, but its lighter weight can keep the overall export costs from rising, Oomo said.
The Niigata Prefectural Inland Water Fisheries Experiment Station, a research laboratory in Nagaoka, which conducts research into breeding technology for koi, rainbow trout and other fish, is working to improve transport technology. In fiscal 2018, the laboratory studied changes in the environment within a plastic bag as it was being used to transport fish. Shoh Sato, manager of the laboratory’s breeding department, said, “We confirmed that the health of fish is heavily influenced by an increase in carbon dioxide levels.”
In fiscal 2019, the laboratory is doing research on how to increase the number of koi that can be transported with the same quantity of water. The researchers aim to control the CO2 level by making the fish less active during transportation through the combined use of anesthesia and a CO2 adsorption agent, Sato said.
The lab is also developing technologies to prevent diseases that affect the value of nishikigoi. The “hole-making disease,” which causes holes to form on a fish’s body, is highly infectious and often fatal. However, the virus that causes the disease remains undetected until symptoms develop. The lab is pursuing research to detect the virus in the mucus on the fish’s skin so it can be diagnosed before symptoms appear.
Nishikigoi production and export is in line with the government’s Cool Japan strategy. Exports of ornamental fish rose 18% on the year to 4.33 billion yen ($40 million) in 2018, twice the level of 10 years earlier. Exports are driven by demand in the U.S., the U.K., the Netherlands and Germany, and in recent years have also been pushed up by wealthy customers in Asia, including in China, Thailand, Taiwan, Indonesia and Vietnam. Koi breeders and the prefectural government will continue to develop new technologies so that can take advantage of new business opportunities.