DISSERTATION RESEARCH: Predation, Competition, and the Role of Behavioral Tradeoffs in a Biological Invasion

Board Of Trustees Of Illinois State University, Normal IL

Investigators

Abstract

This research tests the effects of the predatory mosquito Toxorhynchites rutilus on the outcome of competition between larvae of the Asian tiger mosquito (Aedes albopictus) and the Eastern tree hole mosquito (Ochlerotatus triseriatus) and how that predation affects invasion of A. albopictus into a community of container-dwelling mosquitoes. Although A. albopictus is superior to O. triseriatus in resource competition, in the field, there is little evidence that O. triseriatus is displaced by A. albopictus. Unlike native O. triseriatus, A. albopictus does not modify its behavior in response to T. rutilus predation risk. The investigators will test the hypothesis that this lack of behavioral responses to T. rutilus predation leads to greater vulnerability to predation, which prevents it from displacing O. triseriatus. In addition, the investigators will test whether: (1) competitive interactions between the two prey species are modified by the presence of water-borne (presumably chemical) predation risk cues from T. rutilus; (2) natural abundances of O. triseriatus and A. albopictus increase and decrease, respectively, with the abundance of T. rutilus; (3) there are differences among populations of A. albopictus in behavioral responses to predation risk cues; and 4) a consistent laboratory regimen of predation causes evolution of greater anti-predatory behavioral responses in A. albopictus. Broader impacts: Educational impacts of this research include the completion of the Ph.D. by a graduate student and research experiences for undergraduates who will aid in the laboratory research. Practical impacts include increased knowledge of the role of predators in population limitation of vectors of human disease, and more generally, in limitation of exotic invasive species.