Around the half of June, the firefly (hotaru) season begins in Japan.
Even from the ancient times, the Japanese enjoyed the light shows created by fireflies during warm summer nights, close to the rivers or to the rice paddies.
Special "firefly boats" (hotaru-bune) were used to transport people to the best places for watching fireflies...
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During the Edo period, the custom of catching hotaru 「ホタル or 蛍」 by using fans, traps and nets, became a favorite pastime, as we can see in this ukiyo-e painting:... and around the end of the 18th century, even "firefly lanterns" were sold in Edo.
However, the urban development, the water pollution and the landscape changes caused a severe drop in the number of the fireflies. Japan is probably the only country in the world with firefly protection laws and with a protected habitat for fireflies, established since 1924 in the Shiga Prefecture.
In the Japanese culture, the firefly is a symbol for passionate love, and we can find numerous hotaru references in haiku, love poems and songs...
... like in this song for children, Hotaru koi:
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Another very popular song is Hotaru no Hikari (The Light of the Firefly), a cover of the Scottish folk song Auld Lang Syne, using original Japanese lyrics (the Scottish song was not about fireflies...):On mobile, click on thumbnail for YouTube site/app
Two of the most popular firefly species from Japan, genji-botaru and heike-botaru, were named after a historical event that took place in 1185, the Battle of Dannoura: it is said that the souls of the soldiers killed during the battle, transformed into fireflies. The species of larger fireflies was named after the clan who won the battle, Genji, and the smaller species was named after the defeated clan, Heike.