Chemical pollution in urban larval habitats influences life-history traits and oviposition preferences in the tiger mosquito Aedes albopictus.

Urban artificial containers are highly variable biotic and abiotic environments that strongly influence the ecology of Aedes albopictus, an invasive mosquito vector thriving in urban areas. To understand how these factors shape larval habitat suitability, we characterized micropollutant contamination, physicochemical parameters and microbial diversity in urban breeding sites, both colonized and non-colonized by Ae. albopictus, across the metropolitan area of Lyon, France. A broad spectrum of micropollutants, including pesticides, pharmaceuticals, and banned compounds, was detected at trace concentrations, highlighting the persistent and complex chemical contamination of urban mosquito habitats. Physicochemical parameters varied widely but did not consistently explain colonization patterns. Bacterial and fungal assemblages showed distinct habitat-dependent signatures, reflecting site-specific environmental histories. Based on field data, five breeding sites were reconstructed under laboratory conditions to evaluate their effects on oviposition behavior and life-history traits of Ae. albopictus. Oviposition assays revealed significant differences in comparing habitat attractiveness, while life-history experiments showed that certain reconstructed environments enhanced mosquito performance by accelerating larval development, increasing emergence rate, and extending adult survival. Conversely, one habitat created lethal developmental conditions despite remaining attractive to gravid females. Overall, this study shows that polluted urban breeding sites form complex ecological mosaics in which chemical contamination and microbial communities interact to shape mosquito biology. Better understanding of these interactions could improve predictions of mosquito habitat suitability and enhance oviposition-based surveillance and control strategies in polluted urban environments.