The introduction of Halyomorpha halys, the brown marmorated stink bug (BMSB) (Hemiptera: Pentatomidae), in the USA and Europe has disrupted many established fruit, vegetable and row crop Integrated Pest Management (IPM) programs. BMSB poses a profound threat to many crops because of its broad host range, strong dispersal capacity, well-concealed overwintering populations, as well as the fact that biological control from native natural enemies has been limited and very few registered insecticides are considered effective. The need for sensitive biosurveillance and monitoring tools in uninvaded and invaded regions, respectively, as well as alternative management tactics to reduce insecticide inputs has been paramount. The identification of the BMSB pheromone, (3S,6S,7R,10S)-10,11-epoxy-1-bisabolen-3-ol and (3R, 6S,7R,10S)-10,11-epoxy-1-bisabolen-3-ol in a 3.5:1 ratio and pheromone synergist methyl (2E,4E,6Z)-2,4,6-decatrienoate has rapidly propelled the development of these tools and tactics. Pheromone-baited traps deployed with these stimuli have been evaluated across invaded regions in the USA and Europe and in the native range in South Korea. In every case, traps baited with the combination of the BMSB pheromone and pheromone synergist captured greater numbers of BMSB than traps baited either stimulus alone indicating that these trapping systems can be used for worldwide biosurveillance. Moreover, baited traps have been used as sensitive IPM tools to guide management decisions in affected crops such as apple. Finally, these pheromonal stimuli have served as the basis for successful attract and kill programs in affected crops. While refinement of these tools and tactics continue, their use has resulted in significant reductions in insecticide inputs in apple crops, for example, and successful biosurveillance in newly invaded regions.
Halyomorpha halys (Hemiptera: Pentatomidae) is an invasive species from Asia causing major economic losses in agricultural production in the United States. H. halys is also well known for nuisance problems as massive numbers of adults often invade human-made structures to overwinter inside protected environments. However, overwintering ecology of H. halys in natural landscapes is virtually unknown. We explored forested landscapes in the mid-Atlantic region to locate and characterize natural overwintering structures used by this invasive species. We also confirmed the identified overwintering structures by training and using detector canines in the natural landscapes. Overwintering H. halys were recovered from dry crevices in dead, standing trees with thick bark, particularly oak (Quercus spp.) and locust (Robinia spp.); these characteristics were shared by 11.8% of all dead trees in surveyed landscapes. Dispersal ecology of H. halys were evaluated in the laboratory and field to understand how this pest disperses among its overwintering sites, cultivated crops and wild hosts. In the laboratory, we evaluated the baseline flight capacity of H. halys using flight mill systems. Both foraging and overwintering populations flew on average 2.5 km over a day with some exceptional individuals flying >20 km. In the field, direction observations indicate that H. halys are not likely to initiate flight when temperatures are below 17oC. In addition, H. halys did not initiate flight even under very mild wind (2.4 m/s). We also evaluated the potential of using a portable harmonic radar system to individually track H. halys movements in the field. Our study demonstrates that a portable harmonic radar can be used to track adult H. halys without affecting its survival, walking mobility or flight capacity. In diverse semi-field settings, the success rates of locating radar-tagged H. halys were >85%. The knowledge of overwintering and dispersal ecology reported here would serve as baseline to develop and enhance the management programs of H. halys at landscape levels.
Understanding of dispersal ecology is a critical component to build robust and practical simulation model for insect populations. In this study, we report multifaceted approaches to examine dispersal capacity, behavior and ecology of brown marmorated stink bug (BMSB), Halyomorpha halys (Hemiptera: Pentatomidae). We first evaluated the baseline flight capacity of adults using flight mill systems in the laboratory. The results indicates that this species has strong flight capacity: adults were found yielding flight distances of >2 km in 24 hours with a small portion of the BMSB population capable of flight into double digits. In the field, we made direct observations on BMSB flight to examine free flight capacity and diurnal patterns. BMSB made flight when ambient temperature was >15 oC and flew with the speed of 3 m/s under field conditions, yielding its prevailing flight directions away from the sun’s position over a day. Dispersal capacity and behavior of nymphal stages (2nd through 5th) were also studied. In the laboratory, video image analysis indicates that all nymphal stages have strong walking capacity comparable to adults. In the field, the walking distance of 3rd and 5th instar nymphs on mowed grass was quantified based on direct observation of individuals. Under these conditions, 5th instars moved nearly two-fold greater distances compared with 3rd instars, but surface temperature affected both nymphal stages similarly. Shorter bouts of movement were common at surface temperatures below 25 oC, whereas individuals showed longer walking distances above 25 oC. These baseline knowledge on BMSB dispersal will be key to building and improving simulation model in order to predict spatiotemporal dynamics of the pest populations.