Among the many problematic invasive social insects, the western yellowjacket (Vespula pensylvanica) represents an emerging and harmful introduction. Because Hawaii lacks any native eusocial insects, the invasion of V. pensylvanica poses a potentially devastating threat to the native and largely endemic biota of this region.
A recent immigrant to Hawaii, V. pensylvanica offers an unusual opportunity to study an invasion in progress. Considered an agricultural and recreational pest in its native and introduced ranges, V. pensylvanica is the focus of extensive control programs in Hawaii. In spite of these efforts, there is an incomplete understanding of how endemic Hawaiian communities are affected by this abundant, aggressive and potentially damaging invader.
Studies conducted by Dr. Erin Wilson Rankin investigate the ecological effects of a social wasp invasion on Hawaiian arthropods. Through the study of species interactions and the subsequent population-level effects, a better understanding of the processes shaping food webs may be obtained. Currently, we use a combination of genetic and ecological approaches to quantify invasion impacts and determine whether endemic arthropods are particularly vulnerable to V. pensylvanica predation.
For more information on these invasive social insects and other projects in the Rankin Lab, see Dr. Rankin's web page at UC Riverside.