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Climate change impacts plants and animals in various ways, including poleward shifts of their geographical distribution and changes in their phenology (i.e., date of occurrence of life-stages). Our objective was to determine how phenology can shape the spatial distribution of species in a changing climate (warming trend and increased variability). The applied objective was to take into account the changes in phenology to improve pest management methods. Our model species was the pine processionary moth, Thaumetopoea pityocampa, as its range expansion is climatically-driven. We focused on species phenology on the field in task 1. Data have been collected on sites distributed in different French bioclimate regions and compared to data in the 1970s-1980s. We also collected data on urbanization gradients to explore the effects of urban heat islands. We determined microclimate conditions to estimate the temperature that individuals actually experience. Some individuals (from early to late phenologies) were genotyped to determine whether they come from different populations, since in this case it may explain a larger variability in phenology. In addition, we conducted experiments in controlled conditions in task 2 to determine the effects of temperature on the development of each biological stage and their thermal limits. With RNA-seq approaches, we explored differential gene expression when individuals are exposed to heat stress. In task 3, we developed biophysical models to describe microclimate temperatures. These models were injected in a phenological model calibrated on data of task 2 and validated on data of task 1. We then explored cascading effects of climate change based on changes in life-stage cycle and stage-specific constraints. This phenological model were integrated into a spread model to clearly identify the role of climate change on species distribution via a change in phenology. Task 4 were dedicated to the interaction with the society: an observer network has been created, a survey has been conducted on the needs of the society and a smartphone application has been developed so that anyone can report phenology events of pine processionary moth. Lastly, a real-time map has been generated based on weather forecasts to alert about urtication risks related to the occurrence given life-stages (i.e., to protect human and animal health) and to set up biocontrol methods (i.e., to protect plant health). The ambition of this proposal was to provide the very first study about the inter-relation between phenology and distribution in a changing climate. It is based on groundbreaking scientific approaches (e.g., phenological model based on performance curves, combination of phenological and spread models, real-time risk maps, trade-offs for gene expression after heat stress) and innovative field tools (e.g., network of automated connected traps and smartphone application). The applied ambition was also important with operational progresses (higher effectiveness of biocontrol) and it raised public awareness about local effects of climate change.