Endemic Insects in the Ogasawara Islands: Negative Impacts of Alien Species and a Potential Mitigation Strategy
The impact of invasive alien species on endemic insects in the Ogasawara Islands and current efforts to mitigate this impact are described. Endemic insects have probably been impacted most by the green anole ( Anolis carolinensis carolinensis) as a result of its direct predation pressure, although alien trees such as bishopwood ( Bischofia javanica) and ironwood (Casuarina equisetifolia ) have also had substantial indirect impacts.
Factors causing the decline of species that typify individual habitats — endemic odonates, the Ogasawara tiger beetle ( Cicindela bonina Nakane et Kurosawa, 1959), and the Ogasawara lycaenid butterfly ( Celastrina ogasawaraen-sis Pryer, 1883) — have been revealed, and possible conservation efforts have been developed based on these results. Habitat restoration is now underway. Specific examples of these efforts are presented here.
This study was supported by the Global Environment Research Fund of the Ministry of the Environment of Japan (F-051). I sincerely thank the people who have supported me in the fi eld and who have given critical comments on my study.
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