Predation of the invasive brown marmorated stink bug (Hemiptera: Pentatomidae) by spiders associated with human dwellings

The brown marmorated stink bug, Halyomorpha halys Stål, is an invasive species from Asia. There is increasing interest in the role that native natural enemies play in the mortality of this species in agricultural ecosystems. To date, spiders (Araneae) are an overlooked predator taxon that could play a significant role in H. halys survivorship, especially in urban and suburban settings.  When entering and exiting human-made overwintering sites in the fall and spring, respectively, H. halys are likely to encounter spiders and their webs. To determine the possible impact these spiders may have on H. halys adults, we intentionally placed live H. halys adults in the webs of several spider species found in both indoor and outdoor locations. We recorded: 1) whether predation occurred; 2) feeding duration; and 3) the differential success of web types to retain H. halys. As a measure of natural predation of H. halys by spiders, we also surveyed two buildings (one commercial and one residential) for the presence of the pest in webs. Our results indicate that there is significant predation of H. halys by several spider families (e.g. Theridiidae and Agelenidae) and that H. halys are most likely to be caught in webs with a cobweb-type architecture compared with orb webs. This study is the first to document the important role that spiders found in urban and surburban settings may have on the mortality of H. halys at key points in their life cycle.