Competitive interactions with Aedes albopictus alter the nutrient content of Aedes aegypti.

Competition is often cited as a central force that affects the distribution and performance of organisms. Ecological stoichiometry is the balance of elements within animal bodies that can be affected by resource acquisition and processing, as well as by intra- or interspecific interactions. Though relatively underexplored for mosquitoes, stoichiometry may provide a wealth of information linking ecological interactions to body nutrient content, and potentially on to pathogen transmission. Detritus, which often varies in nutrient content, forms the base of the food web within the small aquatic habitats occupied by larval mosquitoes, and detrital nutrient content can alter mosquito growth, survival, and population growth. The invasive mosquitoes Aedes albopictus (Diptera: Culicidae) and Aedes aegypti (Diptera: Culicidae) interact as larvae in aquatic systems, often altering their adult populations. Herein, we investigated how different detritus combinations as well as how intra- and interspecific densities of Ae. albopictus and Ae. aegypti would affect coexistence; we also measured how nutrient composition (carbon and nitrogen) and stoichiometry (C:N) of adults would vary with those interactions. Ae. albopictus survival, population growth, and stoichiometry were not affected by intra- or interspecific competition; nutrient values did vary with detritus ratios. However, Ae. aegypti nutrient content and stoichiometry and survival were negatively affected within the lowest nutrient environments in the presence of Ae. albopictus, but in the highest nutrient environments, both species showed high survival rates and population growth. This is the first study to show that adult mosquito body nutrients can be altered by interspecific interactions, and as nutrient content in adults has been linked to pathogen transmission, it provides a novel role of competition in affecting disease dynamics.

The readily transformable Impatiens walleriana efficiently attracts nectar feeding with Aedes and Culex mosquitoes in simulated outdoor garden settings in Mississippi and Florida.

Mosquitoes rely upon plant nectars for their energy needs, a trait that has the potential to allow nectar to serve as a platform for producing and delivering toxins to nuisance and/or vector mosquito species. Impatiens walleriana (Order: Ericales, Family: Balsaminaceae) is a readily transformable and widely planted nectar plant that has been previously shown to attract mosquito nectar-feeding. However, those feeding studies were only conducted indoors and did not test if variable environmental conditions will affect nectar feeding. In this study, we tested incidence of nectar feeding from the extrafloral nectaries of I. walleriana with the mosquitoes Aedes aegypti, Ae. albopictus and Culex quinquefasciatus (Order: Diptera, Family: Culicidae) in simulated, outdoor garden settings in Mississippi and Florida. I. walleriana and other common garden plants (in a 1:4 ratio) were placed into a mesh-lined 4'x7' mesocosm along with 50 mosquitoes. To track nectar feeding, the nectar of I. walleriana was tagged with red dye and mosquitoes were analyzed for red dye fluorescence after feeding. Fluorescence analysis demonstrated that 81.9% of male and 86.6% of female mosquitoes fed on the nectar of I. walleriana within 24 h. This suggests that mosquitoes may readily feed on impatiens nectar in outdoor garden settings at temperate and semi-tropical sites, even when alternate common garden plants are available. This attraction capacity is essential for the further consideration of I. walleriana for development as a transgenic, mosquitocidal nectar plant.