Breeding and conservation of Luciola cruciata Motschulsky, 1854 (Coleoptera: Lampyridae) larvae in forests near chemical factories

Abstract

The number of fireflies in Japan has decreased with the development of cities and industries. As a first step toward the regeneration of an environment for fireflies, we report an attempt to breed aquatic firefly larvae. Focusing on the operational stability of equipment used, we use a safety evaluation method like that employed in petrochemical plants. The death of larvae is a major risk in the operational safety of firefly larvae breeding. The larval death scenario is analyzed and clarified using fault tree analysis, demonstrating that reducing operational mistakes in monitoring water flow and temperature conditions contribute most to the reduction of the probability of larval death. An experiment simulating water supply stoppage to estimate the permissible time for a response once the water temperature rose is reported. A firefly larval breeding system equipped with an alarm function for prompting emergency responses is constructed. Fireflies, including mature larvae, are successfully bred and the effectiveness of this system is demonstrated by comparing it with a conventional system. The superiority of the breeding system of this study is indicated by a twofold increase in the yield of mature larvae and the lower expenses related to this strategy.