Meta-Analysis of the Relative Abundance of Nuisance and Vector Mosquitoes in Urban and Blue-Green Spaces

SIMPLE SUMMARY: The increase in global urbanization has highlighted the need for sustainable infrastructure and integration of the urban and natural environment. However, there is concern that an increase in urban blue-green space may create habitats for vector species and potentially increase the risk for transmission of mosquito-borne disease. We conducted a meta-analysis to investigate the effect of urban blue-green spaces on mean mosquito abundance compared to traditional urban cities. We report that the abundance of Aedes aegypti is significantly higher in urban areas void of blue-green space. However, an analysis of three genera (Aedes, Culex, Anopheles), larval habitat guild, and specific taxa (Aedes albopictus and Culex pipiens complex) did not suggest any preference for either habitat considered. Given the lack of available studies and data focusing on contrasting mosquito abundance in blue-green spaces, we recommend that future surveillance studies quantifying mosquito abundance in urban landscapes report the quantitative data necessary to conduct meta-analyses such as this one. ABSTRACT: Blue-green spaces (BGSs), urban areas characterized by the presence of vegetation and or water, and infrastructure form a potential solution for public health threats from increasing urbanization. We conducted a meta-analysis to test the hypothesis that blue-green spaces increase the abundance of nuisance and vector mosquito species compared to non-greened urban areas. After screening 7306 studies published since 1992, we identified 18 studies containing sufficient data from both traditional urban areas and BGSs. We found no significant difference in mean abundance of all mosquito taxa in three genera (Aedes, Culex, Anopheles) when comparing blue-green spaces and non-greened urban spaces. Similarly, a separate analysis of each individual genera found no significant differences. An analysis of the taxa by larval habitat guilds found no differences for container-breeding mosquitoes. Flood-water species tended to be more abundant in blue-green spaces, but the differences were not significant. The individual taxa of Aedes albopictus and the Culex pipiens complex showed no differences between blue-green and urban spaces, while the abundance of Aedes aegypti was significantly higher in traditional urban spaces. Due to the variety existing between and among the several types of blue-green spaces, further studies comparing each unique type of blue-green space or infrastructure will be necessary to draw conclusions regarding the influence of each structure on for urban mosquito communities.