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Container-breeding mosquitoes are important in public health due to outbreaks of Zika, chikungunya, and dengue viruses. This paper documents the distribution of container-breeding mosquito species in Mississippi, with special emphasis on the genus Aedes. Five sites in each of the 82 Mississippi counties were sampled monthly between May 1 and August 31, 2016, and 50,109 mosquitoes in 14 species were collected. The most prevalent and widely distributed species found was Ae. albopictus, being found in all 82 counties, especially during July. A recent invasive, Ae. japonicus, seems to be spreading rapidly in Mississippi since first being discovered in the state in 2011. The most abundant Culex species collected were Cx. quinquefasciatus (found statewide), Cx. salinarius (almost exclusively in the southern portion of the state), and Cx. restuans (mostly central and southern Mississippi). Another relatively recent invasive species, Cx. coronator, was found in 20 counties, predominantly in the southern one-third of the state during late summer. Co-occurrence data of mosquito species found in the artificial containers were also documented and analyzed. Lastly, even though we sampled extensively in 410 sites across Mississippi, no larval Ae. aegypti were found. These data represent the first modern statewide survey of container species in Mississippi, and as such, allows for better public health readiness for emerging diseases and design of more effective vector control programs. [ABSTRACT FROM AUTHOR]

Aedes albopictus has replaced Aedes aegypti in much of the latter species' historic range within the United States. The leading hypothesis for this displacement is exclusion via resource competition; however, the proximate mechanism producing a competitive advantage for A. albopictus over A. aegypti has not been identified. We performed laboratory experiments to test the hypotheses that these species differ in feeding behavior, and that these differences result in differences in survival when resources are scarce. Differences in feeding behavior were assessed in three environments with food (growing microorganisms) available: 1) in fluid only; 2) on leaf surfaces only; 3) or both in fluid and on leaf surfaces. We determined behavior of larvae in these environments, recording their positions (bottom, wall, leaf, top, or middle) and activities (browsing, filtering, resting, or thrashing) using instantaneous scan censuses. A. albopictus spent significantly more time at leaf surfaces, whereas A. aegtdpti spent more time engaging in nonfeeding activities. Both species showed a significant shift in foraging activity toward leaves when leaves were available. In a second experiment, we recorded survivorship for individuals raised in two treatment combinations: whole or half 17-mm disks of live oak leaves, with or without direct access to the leaf surface (controlled using nylon mesh, which allowed movement of microscopic organisms, but prevented mosquito larva movement between container sides). After 31 d, survivorship of A. albopictus was significantly greater than that of A. aegypti regardless of treatments. Moreover, A. albopictus showed significantly greater survivorship compared with A. aegypti when deprived of access to leaf surfaces and in whole leaf disk treatments, suggesting superior resource-harvesting ability for A. albopictus. Our experiments suggest that differences in foraging behavior contribute to the competitive advantage of A. albopictus over... [ABSTRACT FROM AUTHOR]