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Abstract Mosquitoes pose an increasing risk in urban landscapes, where spatial heterogeneity in juvenile habitat can influence fine-scale differences in mosquito density and biting activity. We examine how differences in juvenile mosquito habitat along a spectrum of urban infrastructure abandonment can influence the adult body size of the invasive tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae). Adult Ae. albopictus were collected across 3 yr (2015–2017) from residential blocks in Baltimore, MD, that varied in abandonment level, defined by the proportion of houses with boarded-up doors. We show that female Ae. albopictus collected from sites with higher abandonment were significantly larger than those collected from higher income, low abandonment blocks. Heterogeneity in mosquito body size, including wing length, has been shown to reflect differences in important traits, including longevity and vector competence. The present work demonstrates that heterogeneity in female size may reflect juvenile habitat variability across the spatial scales most relevant to adult Aedes dispersal and human exposure risk in urban landscapes. Previous work has shown that failure to manage abandonment and waste issues in impoverished neighborhoods supports greater mosquito production, and this study suggests that mosquitoes in these same neighborhoods could live longer, produce more eggs, and have different vector potential.
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Evaluating vector mosquito occurrence in residential rain barrels in central Illinois
Abstract Several species of vector mosquitoes (eg Culex pipiens (Linnaeus, 1758), Aedes albopictus (Skuse, 1895)) complete juvenile development in artificial containers. Rain barrels are green infrastructure tools used to conserve rainwater for outdoor use, though they may also serve as a source of mosquito habitat in residential neighborhoods. To identify rain barrel features, maintenance habits, and other conditions associated with the presence of juvenile mosquitoes (ie month), we conducted periodic inspections of rain barrels at 53 households in central Illinois, USA between June and September 2016. Additionally, we administered a questionnaire to the household study participants. In the first month of the study, a diversity of mosquito species was detected in household rain barrels, but from July to September juveniles of Ae. albopictus were predominant. More than half of inspected households contained at least one mosquito-positive rain barrel within the study period. Using stepwise model selection, the strongest predictors of whether or not mosquito juveniles were detected in rain barrels were the use of a preventative measure (eg Bti, chlorine, goldfish), the presence of a mesh covering on the lid of the barrel, and the month of the year. Additionally, the participant questionnaire revealed that the majority of respondents were aware of immediate elimination methods, but few were aware of the need for long-term preventative maintenance of rain barrels against larval mosquito colonization. These findings provide valuable insight into best practices for mosquito prevention in green infrastructure and highlight the importance of proper maintenance and education to minimize juvenile mosquito habitat.
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- Award ID(s):
- 1754115
- PAR ID:
- 10572932
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Medical Entomology
- Volume:
- 62
- Issue:
- 3
- ISSN:
- 0022-2585
- Format(s):
- Medium: X Size: p. 545-551
- Size(s):
- p. 545-551
- Sponsoring Org:
- National Science Foundation
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