Systèmes Ingénieux du Patrimoine Agricole Mondial (SIPAM)

Ayu of the Nagara River System, Japan

GIAHS since 2015


Detailed Information



Site location:  Gifu City, Seki City, Mino City and Gujo City, Gifu Prefecture, Japan

Area of GIAHS: 182,400ha (1,824km2)

Population working for this system: 6,052

Topological Characteristics: forests, rivers and the surrounding plains

Climatic Classification: temperate humid climate

Ethnic Groups/Indigenous People: -

Primary Income Sources: agriculture (paddy rice, upland crops), forestry, fisheries (inland fisheries), commerce and tourism


Global Importance:

The Nagara River and its pristine waters have been conserved as part of the lifestyles of the people. Both the river and ayu are deeply connected to the region economically, historically and culturally.

Food and Livelihood Security

The Nagara River is home to a thriving inland fishery industry that centers on the ayu, accounting for the second greatest yield among all rivers in Japan. Moreover, the ayu which is fished in Gujo City is highly credited for its shape, taste, aroma and firmness and became the very first river fish to be registered as a Regional Collective Trademark by the Japan Patent Office.

The abundant and pristine waters of the Nagara River and its branches irrigate rice paddies over 11,000 ha. Thanks to the accumulation of sand and soil along the river, lands are also perfectly suited to fruit and vegetable cultivation.

Major income in this region is fisheries. It is estimated that the total revenue of ayu across the Gifu prefecture comes to 18.3 million USD per year. Ayu is significant not only for fishery sector but also for tourism. As the unique fishing method attracts many tourists, about 110,000 people visit this region every year. This also contributes to local livelihood and economy.

Biodiversity and Ecosystem Functions

Thanks to abundant and pristine waters, this system has very rich aquatic biodiversity. The Nagara River is home to migratory fish such as ayu, trot, goby, sculpin and etc.. There is high biodiversity not only among fish species but also among amphibians, reptiles and selfish. Some of them are listed in the Red List by Ministry of Environment.

Repeated flood of the Nagara River brought fertile soil and sand to agricultural lands along the river. This made the area suitable for various traditional fruits and vegetables cultivation. Among them, fuyu persimmon and moriguchi radish are famous.

Besides agricultural biodiversity, forests, rivers and agricultural lands provides good habitats for varieties of insects, mammals, birds and so on.

Knowledge Systems and adapted technologies

Fishers in this region has developed many traditional techniques for catching ayu including cormorant fishing, Gujyo fishing, shoal net fishing, night net fishing and vana fishing. These techniques has been developed so that fishers can catch ayu more easily and efficiently with keeping the quality of captured ayu.

As a precious resource, fishers and fisheries cooperatives have made efforts to secure the amount/number of ayu. They have had a strong restriction regarding fishing duration since 1880. Together with that, they have undertook artificial breeding programme since 1915 and release 120 tonnes of artificially-bred ayu fry into the river every year. They also conserve upstream forest in order to keep pristine waters which are one of the crucial requirements for ayu.

Cultures, Value Systems and Social Organizations (Agri-Culture)

Cormorant fishing is not only an ancient tradition dating back to the 8th century but also a part of culture in this region. This fishing method has inherited without essential change and still attracts many tourists.

This system also has a rich cuisine culture which deeply relates to ayu.  Ayu sushi which is made from fermented ayu is provided as end-year gift.  Ayugashi ,ayu-shaped sweets represents the ayu-based culture in this region and is very popular as a souvenir.

Remarkable Landscapes, Land and Water Resources Management Features

The winding river creates a beautiful rural landscape by connecting seamlessly with expansive farmlands and forests.  Human interaction enhances its beauty. In summer, children enjoy swimming, some people enjoy ayu fishing and some people enjoy rafting or river climbing in the Nagara River and its tributary.