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Abstract Dormant propagules can provide a rapid colonization source for temporary aquatic habitats and set the trajectory for community dynamics, yet the egg banks of stormwater management systems have received little attention. We asked which species hatched from the sediment of drainage ditches in Champaign County, IL, and found bdelloid rotifers and ostracods (Heterocypris incongruens) to be the most common taxa. These sites also are colonized by mosquitoes, and we established laboratory experiments to examine interspecific interactions between common co‐occurring taxa.Culex restuanslarvae were reared in the presence or absence ofH. incongruensat two intra‐ and interspecific densities (20 or 40 total individuals) and their survivorship to adulthood, development time to adulthood, adult body size, and sex ratio were determined. Survival forCx. restuanswas significantly lower at high larval density than at low larval density in both treatments.Culex restuanslarvae reared in the presence ofH. incongruenshad a shorter development time to adulthood and emerged as larger adults compared to those reared in the absence ofH. incongruens. The sex ratios in theH. incongruenstreatments were female‐biased whereas those in theCulex‐only treatments were male‐biased. These differences may have epidemiological implications, as only female mosquitoes serve as disease vectors. Our results emphasize the importance of understanding interspecific interactions in influencing larval mosquito development traits.
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Predation differentially structures immature mosquito populations in stormwater ponds
1. Understanding the factors underlying the abundance and distribution of species requires the consideration of a complex suite of interacting biotic and abiotic factors operating on multiple spatial and temporal scales. Larval mosquitoes inhabiting small human‐constructed ponds represent a unique opportunity to investigate the relative importance of these structuring mechanisms while simultaneously generating applied knowledge on mosquito control. 2. A multi‐year field survey of 32 stormwater ponds was conducted in central Illinois (Champaign County). From each pond, data were collected on pond structure type and hydroperiod, the presence/absence of cattails (Typhaspp.), and measures of total nitrogen, phosphorus, and organic carbon, and chlorophylla. The communities of crustacean zooplankton and aquatic insects were characterised, and these taxa were assigned into two main groups: predators and competitors of larval mosquitoes. Structural equation modelling was used to explore the direct and indirect effects of these biotic and abiotic factors on larval density for three species of culicine mosquitoes (Culex pipiens,Culex restuans, andAedes vexans). 3. Hydroperiod had an indirect negative effect onC. pipiensdensity. However, this effect was mediated by predator density; more permanent ponds had more predators, which therefore reduced the density ofC. pipienslarvae.Aedes vexansdensity was positively correlated with predator density. No predictor variables were found that explained variation inC. restuansdensity. 4. This study show that the relative importance of these biotic and abiotic factors varies among species of culicine mosquitoes inhabiting stormwater ponds.
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- Award ID(s):
- 1754115
- PAR ID:
- 10458987
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ecological Entomology
- Volume:
- 45
- Issue:
- 1
- ISSN:
- 0307-6946
- Format(s):
- Medium: X Size: p. 97-108
- Size(s):
- p. 97-108
- Sponsoring Org:
- National Science Foundation
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