PARENT SESSION
Poster Session 29: Predator / Prey Ecology
Thursday, August 11, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal
Predators as modifiers of biological invasions: Does predator avoidance behavior determine the invasive success and impact of the mosquito Aedes albopictus?
Kesavaraju, Banugopan*,1, Alto, Barry2, Juliano, Steven1, Lounibos, Phil2, 1 Illinois State University, Normal, Illinois2 University of Florida, Vero Beach, Florida
ABSTRACT- Aedes albopictus is an invasive container dwelling mosquito native to Asia that invaded North America in the 1980s. Aedes albopictus competes with other mosquitoes including Ochlerotatus triseriatus, a native mosquito. Both A. albopictus and O. triseriatus co-occur with the native predator Corethrella appendiculata in the southeastern part of the United States. Although there are many studies of competitive interactions of A. albopictus and O. triseriatus, there is no information on the behavioral interactions of these prey species with the predator C. appendiculata. We recorded the predation events of C. appendiculata and compared the behaviors that led to prey capture to those that were not associated with capture. Prey capture by C. appendiculata was positively associated with vigorous movement, specifically thrashing, and with the bottom of the container, and negatively associated with resting at the surface. We also tested whether these prey species adopt low-risk behaviors in the presence of the water-borne cues from predation by comparing their behavior in water that had held a feeding C. appendiculata and water that had held only prey. In the presence of water-borne cues from predation, Ochlerotatus triseriatus larvae reduced movement and time at the bottom of the containers. In contrast, the invader A. albopictus did not show any behavioral changes in response to water-borne cues from predation. In a field survey for the presence and abundances of A. albopictus, O. triseriatus, and C. appendiculata at 4 tree hole sites and 4 cemetery vase sites in Florida, the abundance of C. appendiculata was greater in tree holes, and was positively associated with that of O. triseriatus and negatively associated with that of A. albopictus. Previous work has shown that invasion by A. albopictus has had relatively little impact on O. triseriatus abundance in Florida tree holes. Our results support the hypothesis that differential behavioral responses to this predator contribute to the limited impacts of the invader in tree hole habitats.
Key words: Aedes albopictus, Invasion, Predation