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Single and mixed species densities of adult Aedes albopictus and Culex quinquefasciatus were manipulated to determine if different combinations affected their egg laying preference or mortality rates. Oviposition was measured in environments that contained containers of different surface areas (small cups vs. larger bowls), and the number of eggs (Aedes) and egg rafts or larvae (Culex) deposited by each species was examined with respect to intra- and interspecific density treatment levels. Mixed species densities did not have an effect on survivorship, but single species densities did affect longevity, with higher densities leading to shorter life spans in Cx. quinquefasciatus: Cx. quinquefasciatus lived longer than Ae. albopictus overall. There was no significant effect of density combinations on oviposition patterns in either species, but Cx. quinquefasciatus laid more rafts in bowls compared with cups. There is little evidence of adult interactions between these species; however, future experimental work is necessary to more fully characterize the possible effects of adult interactions on these species.

Container systems, including discarded vehicle tires, which support populations of mosquitoes, have been of interest for understanding the variables that produce biting adults that serve as both nuisances and as public health threats. We sampled tires in six sites at three times in 2012 across the state of Mississippi to understand the biotic and abiotic variables responsible for explaining patterns of larvae of common species, species richness, and total abundance of mosquitoes. From 498 tires sampled, we collected >58,000 immatures representing 16 species, with the most common species including Aedes albopictus (Skuse), Culex quinquefasciatus (L.), Orthopodomyia signifera (Coquillett), Aedes triseriatus (Say), Toxorhynchites rutilus septentrionalis (Coquillett), and Culex territans (Walker) accounting for ∼97% of all larvae. We also documented 32 new county records for resident species and recent arrivals in the state, including Aedes japonicus japonicus (Theobald) and Culex coronator (Dyar & Knab). Cluster analysis, which was used to associate sites and time periods based on similar mosquito composition, did reveal patterns across the state; however, there also were more general patterns between species and genera and environmental factors. Broadly, Aedes was often associated with factors related to detritus, whereas Culex was frequently associated with habitat variables (e.g., tire size and water volume) and microorganisms. Some Culex did lack factors connecting variation in early and late instars, suggesting differences between environmental determinants of oviposition and survival. General patterns between the tire environment and mosquito larvae do appear to exist, especially at the generic level, and point to inherent differences between genera that may aid in predicting vector locations and populations.