History of ‘Uotsukirin’ (Fish-Breeding Forests) in Japan

Abstract

The oldest documented reference to ‘uotsukirin’ (fish-breeding forests) in Japan is from the tenth century, and describes one in Tokushima Prefecture. Uotsukirin existed throughout Japan since the seventeenth century. Their main purpose was to promote sardine fishing, because sardines were an important industrial resource used to make commercial products including foods, lamp oil, and fish fertilizer at the time. In 1623, in the southern part of present-day Oita Prefecture, the first lord of the fief proclaimed, “I have heard that sardines do not come near the coast if the trees are not dense in the mountains along the seashore. To promote sardine fishing, therefore, I firmly forbid the felling of trees in small islands and the slash-and-burning in the mountains near the creek.” He had become aware of the importance of the sardine in 1604. Huge amounts of sardines, herrings, and whales were transported into the inland as fish fertilizer in Japan in the seventeenth–nineteenth centuries, suggesting that the Japanese agriculture developed nationwide and on a large scale during the pre-modern Edo period (1603–1867).

In 1897, the Japanese government enacted the Forest Law. Japan’s first protected forest as defined by a modern legal system was introduced in this Forest Law. In the twentieth century, research on the relationship between inland forests and the sea from the viewpoint of the natural sciences first appeared. Dr. Endo Kichizaburo, a professor at Sapporo Agricultural College who researched seaweed, described in 1903 that the cause of ‘Isoyake’ (rocky-shore denudation) was the devastation of inland watershed forests. Dr. Inukai Tetsuo, professor of zoology at Hokkaido University, wrote in 1951 that forests all over Japan used to be uotsukirin. Nowadays, fishermen actively plant trees all around Japan.