著者

水井 颯麻 Quang-Tuong Luong 勝原 光希 中田 和義

出版者

日本甲殻類学会

雑誌

CANCER (ISSN:09181989)

巻号頁・発行日

vol.32, pp.19-27, 2023-08-01 (Released:2023-09-06)

参考文献数

30

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We conducted laboratory experiments to examine the predation effects on larvae of two Japanese native dragonfly species by the North American invasive crayfish Procambarus clarkii. We put a larval individual of either Trigomphus interruptus or Coenagrionidae spp. in experimental aquaria, and after 24 hours we added an individual of P. clarkii of two different body size groups; small size group: total length (TL)<50 mm and large size group: TL>60 mm. After seven days, we observed whether the larval individuals of the dragonflies survived or not. We confirmed the severe predation on both of the two taxa of dragonfly larvae by P. clarkii. In T. interruptus, the survival rate was significantly lower compared to the control group (i.e., no crayfish) both in the small and large size groups. In Coenagrionidae spp., the survival rate of larvae in the small size group was significantly lower than the control group. In the large size group of P. clarkii, predation on the dragonfly larvae was also observed, but there was no significant difference compared to the control group. These results indicate that P. clarkii especially in small size can have a marked negative effect on dragonfly larvae through severe predation, if P. clarkii invades the habitats of dragonfly larvae.