Measuring spatial distribution of seasonal dispersal of the kudzu bug, Megacopta cribraria (Hemiptera: Plataspidae) in kudzu and soybean

The invasive kudzu bug, Megacopta cribraria (F), has spread to 13 states from Maryland to Louisiana since detection near Atlanta, GA in late 2009. To determine what environmental factors affect M. cribraria dispersal, cylindrical white sticky traps were deployed and inspected weekly at 50m intervals in the four cardinal directions originating from a large kudzu patch located in south Georgia.  Every two weeks, a 4.6m² patch near the origin was treated with fluorescent dye.  Captured insects were enumerated, sexed, and inspected under a blacklight to assess flight timing, direction, and distance. Additionally, egg masses were collected weekly from kudzu shoots to assess oviposition timing and parasitism. A strong bias for increased captures was detected in traps adjacent to soybean compared with planted pine. Across all traps, distinct peaks in M. cribraria captures were observed coinciding with emergence of first and second generations followed by dispersal from senescing kudzu and soybean to overwintering sites. Oviposition occurred from April through late June.  Generally speaking, there were more bugs captured within 100m from the origin compared to more distal locations. Late in the year, dispersal from the kudzu greatly increased in traps farther from the origin.  Fewer bug captures were observed during weeks with high precipitation. These results strongly suggest that this species has a greater propensity for flight and therefore new habitat colonization in the early spring.  Individuals appear to be more sedentary from July through October until they disperse into wooded habitats for overwintering.