Effect of Climate Warming on Mosquito Population Dynamics in Newfoundland

Mosquitoes are key vectors of several infectious diseases affecting humans and animals. In North America, Culex mosquitoes are primary vectors of West Nile virus, St. Louis encephalitis, and Japanese encephalitis, as well as pathogens that impact birds and horses. The Culex life cycle consists of four stages, eggs, larvae, pupae, and adults, each with distinct development and mortality rates. Only active (non-diapausing) adults can reproduce, and environmental factors such as temperature, photoperiod, and rainfall influence population dynamics and stage-specific abundances. We develop a stage-structured model that integrates historical climate data and available experimental data to describe how key climate variables regulate life history parameters. Specifically, oviposition rates depend on temperature, maturation and survival are influenced by both temperature and rainfall, mortality is modeled as temperature-dependent, and diapause induction and termination are driven by photoperiod. Unlike many previous models focused on tropical mosquitoes, our framework explicitly incorporates diapause, a critical adaptation for temperate Culex populations. Simulations reveal strong nonlinear responses to warming, moderate temperature shifts amplify the differences in mosquito abundance across rainfall regimes, whereas higher warming leads to convergence at consistently high densities. Rainfall amounts determine whether populations remain suppressed, variable, or strongly amplified, whereas warming extends the active season and elevates population abundance. These results underscore the importance of jointly considering temperature, rainfall, and photoperiod in predicting mosquito dynamics. Our findings suggest that climate change may expand the seasonal window of mosquito activity and raise vector abundance, thereby increasing opportunities for pathogen transmission. The model provides a mechanistic framework for exploring how interacting climate drivers shape vector ecology and highlights priorities for data collection and adaptive control strategies under environmental change.