大山ダムにおけるホタルビオトープの創出と生息環境調査

抄録

The Japanese firefly Luciola cruciata (Japanese name: Gennjibotaru) is one of the most popular fireflies in Japan. Strong and fantastic flashing light of the male firefly in summer night has historically attracted deep interest of Japanese people. The firefly can be commonly found in poems and novels written in Japanese. Unfortunately, the population of the Japanese fireflies is gradually declining due to some reasons such as the greenhouse effect and crop-spraying. In order to preserve the fireflies and grow their population we set up a biotope consisting of a brook and a pond in Hita city, Oita prefecture, Japan. The biotope was designed to resemble the traditional Japanese landscape called Satoyama. Of course, live snails Semisulcospira libertina (Japanese name: Kawanina) were initially supplied to feed the larval stage of the fireflies. The quality of water flowing in the biotope was carefully controlled. A change in the population of the fireflies in the biotope over 10 years and related information are reported in this technical note.