2019 年 23 巻 1-2 号 p. 21-28
In the Ogasawara Islands much effort has been invested in the management of alien invasive species. There are still many challenges to overcome to achieve management goals such as eradication and containment. In all cases, after determining the target alien invasive species for management, effective, low cost management strategies are needed. Essentially there is a need to establish such management strategies against alien invasive species, that both 1) specify what kind of management interventions to take and 2) provide a spatially explicit management plan. In this paper I focus on three problematic alien invasive plants, Bischofia javanica, Leucaena leucocephala and Casuarina equisetifolia. Aggressive management efforts have been made against these, but in some cases no strategic management plan was established so they still cause problems in the Ogasawaras. For two of the three species, there is a lack one or both of 1) effective management interventions and 2) a spatially explicit management plan. First, I explain what an effective management plan consists of, with one specific case in Japan. Then, I overview the current status and future challenges toward managing these three alien invasive species. Finally I discuss what further steps are needed for realizing effective management of alien invasive species in the Ogasawaras.
