Intraguild predation among larval treehole mosquitoes, Aedes albopictus, Ae. aegypti, and Ae. triseriatus (Diptera: Culicidae), in laboratory microcosms.

We compared the tendency for 4th-instar larvae to prey on newly hatched larvae, and the vulnerability of those 1st instars to such predation for Aedes triseriatus (Say), Ae. aegypti (L.), and Ae. albopictus (Skuse), all container-breeding mosquitoes. The latter 2 species were introduced to North America and are now sympatric with Ae. triseriatus, a native species in eastern North America. The experiment also enabled the assessment of species-specific influences of food supplements and spatial heterogeneity on predatory behavior. Ae. triseriatus was substantially more predatory and less susceptible to attack than the other 2 species. These differences were amplified in food-deprived and spatially simple conditions, indicating that Ae. triseriatus predatory behavior may have important retarding effects on the colonization of occupied treehole habitats by Ae. albopictus. Ae. aegypti and Ae. albopictus were similar in imposing little (Ae. aegypti) or almost no (Ae. albopictus) predation on 1st instars and in being susceptible to predation by Ae. triseriatus. The general lack of species-specific differences between Ae. aegypti and Ae. albopictus indicates that interspecific predation is not a likely explanation for the rapid displacement of Ae. aegypti by Ae. albopictus in domestic containers in the southeastern United States.