Prairie Research Institute
Event Detail Information
INHS Seminar - Dr. Robert Marquis - Impacts of Native Shelter-Building Insects on the Success of the Invasive Asiatic Oak Weevil, Cyrtepistomus castaneus (Roelofs, 1873)
The causes of success of invading species are varied. The Asiatic oak weevil is one of the most abundant insect herbivore species in Missouri oak-hickory forests, and is common throughout the eastern U.S. Native shelter-building insects, via their impacts as ecosystem engineers, appear to engender the success of this species locally. Abundance of weevils is higher in leaf rolls and leaf ties, made by a variety of species of caterpillars, than on leaves that have not been rolled or tied. The presence of leaf ties in particular changes abundance of the weevil on individual trees, the relative abundance on different tree species, and the amount of damage per tree species. Finally, results from longterm monitoring of an experimental forestry study show that weevil abundance on black and white oak trees in successive years is positively influenced by the abundance leaf rolling caterpillars on those trees in previous years. Our study appears to be the first example of native insect species positively influencing the success of a non-native insect species. In this case, the impact is through ecosystem engineering.