Colonization of rock holes by Aedes albopictus in the Southeastern United States

Aedes albopictus was collected from water-holding rock holes along 3 streams in Georgia and 1 in South Carolina. To compare the occurrence of Ae. albopictus and Aedes atropalpus, rock holes were sampled for immature Aedes at 2 sites where there were numerous rock holes harboring mosquitoes. At 1 of these sites, tree holes and various types of artificial containers were also sampled for immature Aedes. At both sites, immature Ae. albopictus occurred in rock holes much less frequently than the rock-pool specialist, Aedes atropalpus. Moreover, the distribution of Ae. albopictus was limited to rock holes in less flood prone locations, whereas Ae. atropalpus was often a common mosquito even in rock holes that were among the most susceptible to flooding by rising stream levels. By contrast, Ae. albopictus was frequently found in the samples from tree holes and artificial containers. Thus, it appears that riverine rock holes that are flooded frequently may be, at best, marginal habitats for Ae. albopictus.