Laboratory and Field Investigation of Biological Control for Brown Marmorated Stink Bug (halyomorpha Halys (stål) (hemiptera: Pentatomidae))

Conservation biological control manipulates habitat characteristics to enhance natural enemy populations and ultimately reduce pest density. These practices can be most effective early in the growing season when pest populations are low. Early season predator impacts on these pests can include both direct consumption of herbivores and non-consumptive effects such as superfluous killing, both of which provide pest suppression. We combined laboratory feeding trials, and a field cage experiment with molecular gut-content analysis to explore the effects of striped lynx spiders (Oxyopes salticus Hentz) on brown marmorated stink bugs (Halyomorpha halys (Stal)). The laboratory feeding trials revealed that lynx spiders did attack stink bugs but that stink bug DNA had a short DNA detectability half-life within lynx spider guts. To simulate field conditions where these two species could interact in both early and late season, we manipulated the density and relative abundance of stink bug nymphs and adults in the presence and absence of lynx spiders. There was no effect of treatment on recovery of either adult stink bugs or nymphs. Although dead stink bugs were recovered, we found no evidence of consumption through molecular gut-content analysis. Contrary to expectations that generalist predators would have the greatest impact on pests early in the growing season, our results suggest that lynx spiders are unlikely to exert substantial early season control. Biological control might be most effective when utilizing multiple predator species as part of a complex of natural enemies, so spiders acting in concert with other generalist predators could be capable of suppressing pest populations.