How Unagi Culture Continues to Evolve through a Pioneering Spirit

A hundred years of Unagi farming: a history of constant innovation, inheritance, and wisdom

　Unagi farming started at Lake Hamana in 1891, more than 100 years ago. It started when Kurajiro Hattori from Fukagawa, Tokyo, determined that the warm land of Hamamatsu is perfect for farming unagi, and developed an eel farm. Afterwards in 1971, Keijiro Muramatsu invented a method of raising Shiroko unagi that has just hatched from an egg, which made it possible to significantly increase the production volume.

One of the factors that brought about aquaculture in Lake Hamana is its environment that makes it easier to catch fry. Currently, unagi farming is carried out by cultivating them from a natural fry. Unagis are said to spawn in the Mariana Strait, but its fry swim through the Pacific Ocean and come to Lake Hamana and the Tenryu River in search of fresh water. From there, the farmers transfer them to a safe, well-maintained aquaculture pond to raise them. In addition, the fact that the water needed for aquaculture could be supplied from the abundant groundwater in the Mikatahara Plateau region, and the average annual temperature around Lake Hamana is around 15°C, which exhibits a relatively warm climate, has also contributed to the development of its aquaculture.

However, we must not only appreciate the environment, but also the efforts of the farmers themselves. Takushi Nagata, a member of the Lake Hamana Fish Farming Cooperative Association, describes the difficulty of unagi farming, and the efforts of their predecessors, as follows:

“In the past, the probability of an unagi growing into adulthood via farming was said to be 30%. This is because unagis are carnivores that eat each other at times, and there were no housed farming grounds in the past, when they had to face the risk of unagis being caught by birds, etc. The predecessors made various efforts from an early stage, such as raising groups of unagis in separate ponds based on size, etc., which now boasts a growth success rate of more than 80%. When they are a fry, it takes a lot of effort in feeding them, and raising them is definitely not an easy feat. But as each life is precious, we do everything we can to prevent any deaths.”

The Unagi restaurants born in proximity to Unagi farms and the landscape of Hamamatsu

Hamamatsu City has traditionally had a large number of unagi restaurants due to its proximity to the unagi farms. There are two types of kabayaki, a representative Japanese unagi dish: the “Kanto style,” in which the unagi is cut open from its back, as it was considered bad luck to cut the stomach open due to the prevalent samurai culture at the time, and then skewed with bamboo sticks, steamed, and then grilled until they’re puffy; and the “Kansai-style,” in which the unagi is cut open from the stomach, as it is considered good luck in the said region of merchants to communicate while putting their differences aside (which is termed, “splitting the stomach” in Japanese), then skewed with metal bars, and thoroughly grilled until it turns aromatic, without first steaming it. As Hamamatsu is located right in the middle, it is in an unusual location that allows you to taste both styles of unagi.

"However, after unagi farms started springing up at Lake Hamana, our first generation owner must have taken advantage of that. There were about 100 unagi restaurants around here at one point, but now, there’s only about 70.

I think it’s only in Hamamatsu where you have restaurants located so close to an unagi farm. Hamamatsu was originally a prosperous, inn town with plenty of wealthy people due to the flourishing of their cotton industry, which must have created the Hamamatsu food culture of eating unagi. I’ve eaten unagis from numerous regions including foreign ones, but the unagis nurtured at Lake Hamana are definitely the best choice in making our traditional kabayaki."

A sustainable way of using every part of the process

In Hamamatsu, there are many processed products such as confectioneries and souvenirs that use unagi as the raw ingredient. In cooking, unagi is an ingredient that can be eaten in its entirety without wasting any part, but in manufacturing processed products, its head and bones tend to be thrown away. But there’s a sweet potato called “Unagi Potato” that is cultivated using fertilizers made from such unagi parts that are usually thrown away. Sweet potato itself is a regional ingredient that has started being cultivated hundreds of years ago in the Enshu region to the west of Shizuoka Prefecture. But what has led them to start using unagi as the fertilizer? Takuma Ito, a member of Unagi Potato Cooperative, explains its story as follows:

What’s interesting about the “unagi potato” is that it has led to the creation of a cute mascot, as well as the development of sweet potato snacks, merchandise, etc. It’s also quite common for people to find out about “unagi potato” through the mascot.

"We currently sell overseas to Taiwan, Hong Kong, Malaysia, Canada, Singapore, etc. At times, we also have our customers who come to know our products through our mascot. Our hope is to promote our brand, and educate the public about recycling unagi as a fertilizer via the mascot. My wish is for this activity to lead to the creation of a sustainable society centered on agriculture.”

Its aquaculture started 100 years ago, and has since developed an unagi food culture, and the spirit of recycling the ingredient without wasting any part of it. What seems to emanate from all of that is the pioneering spirit of creating a pathway from the very beginning. This essentially sums up the Hamamatsu spirit of “yaramaika” (a spirit of boldly challenging oneself to any endeavor one faces).