Tuesday, August 7, 2007

PS 30-95: Do forested areas impede invader dominance? Predator-mediated coexistence of invasive and native container-dwelling mosquitoes

Banugopan Kesavaraju, Kavitha Damal, and Steven A. Juliano. Illinois State University

Aedes albopictus is an invasive mosquito and a vector of arboviruses including dengue and west Nile. The native predatory larvae of C. appendiculata feed on mosquito larvae like Ochlerotatus triseriatus, a native mosquito, and A. albopictus. Previously, we have shown that in the presence of water-borne cues from predation, O. triseriatus larvae show increased levels of reduced activity compared to A. albopictus. We tested whether the anti predatory behaviors of A. albopictus evolve over generations if they are subjected to consistent selection by predation. There was no change in A. albopictus behaviors. In a field survey for the presence and abundances of the three species at 12 sites in Florida, the abundance of C. appendiculata was greater in tree holes (forested areas), and was positively associated with O. triseriatus and negatively associated with A. albopictusAedes albopictus were dominant and their abundances in developed urban areas were twice as those found in forested areas. Our results support the hypothesis that differential behavioral responses to this predator contribute to the limited impacts of the invader in forested habitats.