Variation in performance of two co‐occurring mosquito species across diverse resource environments: insights from nutrient and stable isotope analyses

Abstract

1. Inputs of animal and plant detritus are the main energy sources for food webs in a number of isolated container systems, including discarded automobile tyres and tree holes. Containers are dominated by mosquitoes in the genera Culex and Aedes, which among other differences often engage in different foraging behaviours. We hypothesised that because Aedes feed more by browsing surfaces, whereas Culex often filter the water column, these mosquitoes would show variation in performance and differentially affect detritus. Effects of different ratios of animal and plant detritus on survival, mass, and development time for two common container mosquito species, Culex restuans L. and Aedes albopictus Skuse, were examined. We also quantified detrital contribution to biomass via isotopic and nutrient analysis and the effect of larvae on detrital decay.2. Adult male and female mass of both species was highest with some animal detritus and lowest in only leaf detritus. Aedes albopictus survival was higher than C. restuans across most detritus ratios.3. Aedes albopictus had higher values of 15 N and in some cases 13 C across all detritus ratios compared with C. restuans; A. albopictus had lower nitrogen in tissue. Aedes albopictus appeared to be more efficient at obtaining potentially limiting nutrients and had a greater overall effect on detrital decay -a possible consequence of greater foraging effort.4. Findings further support the view that mosquito performance can be influenced by detritus type, and provide a more precise hypothesis (i.e. lower need for nitrogen) that may explain the superior competitive ability of A. albopictus over other container mosquitoes.

What Can Larval Ecology Tell Us About the Success ofAedes albopictus(Diptera: Culicidae) Within the United States?: Table 1.

“…albopictus. Like Winters and Yee (2012), these relative amounts were reversed in pure animal, with carbon 55% and nitrogen 7%. Thus, both studies suggest that body nutrients can be altered in adult mosquitoes based on exposure to different detrital sources as larvae.…”

“…The data generally support higher overall performance for Ae. albopictus in animal-versus plant-derived diets (Daugherty et al 2000, Yee et al 2007a, Murrell and Juliano 2008, Winters and Yee 2012, Bara et al 2014, Yee et al 2015b); however, Barrera (1996) found that Ae. albopictus survived longer when grown on leaves versus an artificial diet of bovine liver powder and yeast.…”

“…Both stoichiometry and stable isotope analyses of mosquitoes are only now becoming an area of interest, and at present, there are a limited number of studies using either approach (Kaufman et al 2010, Hood-Nowotny 2012, Winters and Yee 2012, Gilbreadth 2013, Young et al 2014, Yee et al 2015b, with only two published studies involving Ae. albopictus (Winters andYee 2012, Yee et al 2015b).…”

“…After allochthonous detritus enters a container, it breaks down via the action of microorganisms and is transformed into new microorganism cells and waste products, which are then ingested by foraging larvae. Thus, an analysis of mosquito elemental composition and variation (i.e., stoichiometry) can inform not only of differences among species, but also where those elements come from (Kaufman et al 2010, Winters and Yee 2012, Yee et al 2015b. Besides stoichiometry, which deals specifically with nutrient composition and allocation patterns of elements like carbon, phosphorus, and nitrogen, stable isotopes, which use the rarer isotopic forms of common biological elements to assess diet and tropic position, also have the potential to lead to a deeper understanding of insect and mosquito ecology (Hood-Nowotny and Knols 2007).…”

“…albopictus. Winters and Yee (2012) grew larval Ae. albopictus under different ratios of red maple (Acer rubrum L.) and Drosophila melanogaster in the lab.…”