A project team consisting of Tokyo Metropolitan University, Forestry Research Institute, and Hachijojima Hachijocho, Tokyo, which was formed to control the outbreak of Hachijojima, is an effective hydrogel bait agent for this species and the participation of residents. Announced that it has developed a type control program and confirmed a high control effect.
The alien species, Phragmites australis, has become more dense and the damage caused by invasion of houses has begun to worsen on Hachijojima from around 2016.Preliminary research has shown that this species does not like commercially available ant-specific baits (poisonous food) at all, so it is thought that it is necessary to develop new bait agents that have never been used to control this species. rice field.This group focused on the extremely water-rich jelly-like "hydrogel bait", which has been used overseas in recent years but is the first trial in Japan.
A hydrogelbait containing sucrose water was found to be very attractive for the Phragmites australis, which prefers a liquid diet containing sugar.As an insecticidal ingredient, thiamethoxam showed a high effect, although the effect was insufficient with fipronil and boric acid, which are effective in other species of ants.Therefore, a hydrogel bait agent containing sucrose water and thiamethoxam was distributed to the residents, and the residents themselves planned and executed a regional simultaneous control test in which the agents were sprayed all at once on the premises.
As a result, it was confirmed that the number of Phragmites aeruginosa was significantly reduced from several weeks to one month after the simultaneous spraying.In addition, in the ex-post questionnaire of the residents who participated in the simultaneous control test, it was said that the ease of installing the bait agent and the control effect on this species were highly evaluated.
In this study, the hydrogel bait agent introduced for the first time in Japan can control Hirafu siri, which is difficult with commercial agents, and even if the community-based control program is a remote island with scarce human resources. It has been shown that it can be an effective means for controlling alien species.In future research, it is planned that the residents will take the initiative in monitoring for the evaluation of the control effect.
