Metcalfa pruinosa (Hemiptera: Flatidae) is a invasive and harmful insect in South Korea. It is originated from the Nearctic region. Since M. pruinosa was first identified in South Korea in 2005, it dispersed throughout the country. In this study, we investigated the dispersal ability of M. pruinosa in the field in three different levels: 1) short distance movement, 2) flying movement, and 3) dispersal distance in large area in the two different landscape types (open canopy and forest with covered canopy). Our results showed that the movement ability of M. pruinosa was weak in walking. However, it displayed long dispersal distance that increasing dispersal distance in each year. These results can be used for modelling dispersal distance of the species.

We conducted a investigation for dispersal ability of Aedes albopictus, a dengue vector mosquito, using mark-release-recapture method in Korea. A certain number of fluorescence marked Ae. albopictus was released in four different habitats – urban (Cheonan), suburban (Jochiwon), port (Pyeongtaek), and airport (Cheongju), and sticky traps and BG-traps were used to recapture the mosquito in designated time period. In case of urban and suburban areas, 100 sticky traps were used in 3-week period for both regions, and 19 BG-traps and 15 BG-traps were used in 36-hour period for urban and suburban areas respectively. Using sticky trap, 21 from 1,300 released mosquitoes (1.62%) were recaptured in urban area; while in suburban area, only 2 individuals (0.1%) were recaptured. Most of them were recaptured within 100m from releasing point and about 40% were within 20m distance. When BG-traps were used, 35 from 900 released mosquitoes (3.8%) were recaptured in urban area; while 26 mosquitoes (2.8%) were recaptured in suburban area. The maximum distance of dispersal was 200m in urban and 100m in suburban area, while most of them were recaptured in 50 ~ 80m range. In case of port and airport area, 15 and 10 BG-traps were used respectively to recapture 1,000 released mosquitoes in 5-day period. In port area, 23 mosquitoes (2.3%) were recaptured; while 166 mosquitoes (16.6%) were recaptured in airport area. The maximum distance of dispersal was 130m in both areas; while most of them were recaptured in 50m range. In conclusion, Ae. albopictus has a narrow dispersal range compared to other mosquitoes, a typical characteristic of genus Aedes, and their dispersal ability is greatly affected by various environmental factors. These results can provide basic information for effective prevention of Ae. albopictus and overseas inflow of dengue fever.

Paromius exiguus (Distant, 1883) is a serious insect pest in rice field adjacent to reclaimed land. They suck young ear of rice causing empty head of grain or pecky rice grain. During 2010 to 2012, we conducted to investigate the host-plant change of P. exiguus in Siwha reclaimed land, Hwaseong-si. In 2012, we also studied dispersal ability of P. exiguus from reclaimed land to adjacent rice fields. In early May, the adults aggregated on the grain parts of cogon grass (Imperata cylindrica) (Poales: Poaceae) after overwintering, and laid their eggs and nymphs developed into adults on the same host plants from middle May to late June. Second generation was observed at wood small-reed (Calamagrostis epigeios) (Poales: Poaceae) from late June to late July. At shooting stage of rice, adults moved to adjacent rice fields and third generation might be started. Although dispersal ability of adult of P. exiguus penetrated about 10 km into inland areas of Hwaseong-si, number of individuals of P. exiguus population was significantly declined with increasing distance from reclaimed land (Pearson’s correlation coefficient, r=-0.7357, p<0.0001). Unfortunately, further studies on population dynamics of P. exiguus in rice fields could not investigated, because pesticides were widely sprayed by aerial application in 14 August, 2012. Nevertheless, this results will be a useful information for management and control of P. exiguus in rice fields adjacent to reclaimed land.