The ecological impact of an introduced population on a native population in the firefly Luciola cruciata (Coleoptera: Lampyridae).
In Japan, Tatsuno Town has been famous for many Luciola cruciata fireflies emerging every summer at least since the 1920s. However, in the 1960s, L. cruciata fireflies were intentionally introduced from the Lake Biwa area into Matsuo-kyo, the most famous habitat of fireflies in that town. In this study, I examined ambient temperatures and flash rates of L. cruciata at four sites including Matsuo-kyo in the Tatsuno area and two sites in the Lake Biwa area. The linear regression of flash rates on temperatures indicated that the Matsuo-kyo population was distinct from the other three populations native to the Tatsuno area, but similar to the two populations native to the Lake Biwa area in terms of flash rates. These results were also supported by a recent molecular biological study, suggesting that the introduced fireflies had a strong ecological impact on the native ones at Matsuo-kyo. The present study emphasizes that we should not transport and release L. cruciata fireflies without careful consideration.