Case studies on the anti-bloodsucking measure against Hirosia iyoensis (Tabanidae) by the box trapping methods

Abstract

Hirosia iyoensis (Shiraki, 1918) is one of the most harmful horse flies for human in Japan because of its sudden outbreak in a short time and its persistent bloodsucking habit. Females of H. iyoensis develop their oocytes in the first gonotrophic cycle without blood intake. Since 1997 we have been studying to control them at some mountainous areas in Toyama Prefecture, central part of Japan, where the great numbers of H. iyoensis occur every year. Eradication of H. iyoensis seems to be unsuccessful by the application of insecticides or the common trapping methods because of autogeny and widespread habitat. On the other hand canopy traps and box traps baited with carbon dioxide (CO₂) were used to mass-capture H. iyoensis. In this study I investigated the anti-bloodsucking measure of H. iyoensis using box trap in camping site and furniture production factory. In the first case two box traps were placed in the camping site in 2001 and 2002, where the great numbers of H. iyoensis were occur every year. Total 8,915 H. iyoensis were captured for 2 seasons. In the second case five box traps were placed in the furniture production factory in 2001, where H. iyoensis and Tabanus rufidens came flying for bloodsucking into the factory. Total 8,967 tabanid-flies were captured for 37 days. In two cases mentioned above, there was no complaint of the bloodsucking from the participants and employees. It was supposed the trap capture was effective to prevent the people from the bloodsucking damage by H. iyoensis.