The influence of weather on the population dynamics of common mosquito vector species in the Canadian Prairies

Abstract

AbstractBackgroundMosquito seasonal activity is largely driven by weather conditions, most notably temperature, precipitation, and relative humidity. The extent by which these weather variables influence activity is intertwined with the animal’s biology and may differ by species. For mosquito vectors, changes in weather can also alter host–pathogen interactions thereby increasing or decreasing the burden of disease.MethodsIn this study, we performed weekly mosquito surveillance throughout the active season over a 2-year period in Manitoba, Canada. We then used Generalized Linear Mixed Models (GLMMs) to explore the relationships between weather variables over the preceding 2 weeks and mosquito trap counts for four of the most prevalent vector species in this region:Oc. dorsalis,Ae. vexans,Cx. tarsalis, andCq. perturbans.ResultsMore than 265,000 mosquitoes were collected from 17 sampling sites throughout Manitoba in 2020 and 2021, withAe. vexansthe most commonly collected species followed byCx. tarsalis.Aedes vexansfavored high humidity, intermediate degree days, and low precipitation.Coquillettidia perturbansandOc. dorsalisactivity increased with high humidity and high rainfall, respectively.Culex tarsalisfavored high degree days, with the relationship between number of mosquitoes captured and precipitation showing contrasting patterns between years. Minimum trapping temperature only impactedAe. vexansandCq. perturbanstrap counts.ConclusionsThe activity of all four mosquito vectors was affected by weather conditions recorded in the 2 weeks prior to trapping, with each species favoring different conditions. Although some research has been done to explore the relationships between temperature/precipitation andCx. tarsalisin the Canadian Prairies, to our knowledge this is the first study to investigate other commonly found vector species in this region. Overall, this study highlights how varying weather conditions can impact mosquito activity and in turn species-specific vector potential.Graphical Abstract