First detection of Agrilus planipennis in Connecticut made by monitoring Cerceris fumipennis (Crabronidae) colonies

Smoky winged beetle bandits, Cerceris fumipennis Say, digger wasps in the family Hymenoptera: Crabronidae: Cercerini, provision their underground nests with adult metallic wood-boring beetles (Coleoptera: Buprestidae). Researchers, as well as engaged community volunteers, in several states have monitored female wasps returning to their nests as a means to detect invasive buprestid species. In this paper, we report the first detection of emerald ash borer (Agrilus planipennis Fairemore), an invasive beetle responsible for killing millions of ash trees in North America, in Connecticut by C. fumipennis and discuss its relationship to A. planipennis survey efforts by other modalities in the state. We also report detections of A. planipennis by C. fumipennis in Illinois, New York and Ontario; all of which were made after it was known the beetle was in the area. These findings support the use of C. fumipennis as a biomonitoring tool and bolster the use of engaged volunteers.