Astata unicolor (Hymenoptera: Crabronidae) Population in Oregon With Observation of Predatory Behavior on Pentatomidae

Abstract

Predatory wasps are one of the few natural enemies to attack late instar pentatomid nymphs and adults. However, there is a substantial lack of information about their flight and nesting behavior, making them poorly understood. We report 3 yr of observational data of Astata unicolor Say 1824 foraging behavior and phenology from a residential site in Portland, OR. A. unicolor attacked and paralyzed at least four hemipteran species, and 64% of paralyzed prey were from the invasive Halyomorpha halys (Stal; Hemiptera: Pentatomidae). Peak flight occurred between late July and mid-September. Though unmanaged and solitary, A. unicolor’s preference for H. halys demonstrates that native predators contribute to mortality and potentially management of economically important insects. This is one of the few studies to document predatory wasps’ potential for biological control of H. halys. Additional work on Astata is necessary to determine whether trap nesting, dispersal, or habitat enhancement, broadens the potential for expanded biological control.