Understanding how events throughout the annual cycle are linked is important for predicting variation in individual fitness, but whether and how carry-over effects scale up to influence population dynamics is poorly understood. Using 38 years of de-mographic data from Algonquin Provincial Park, Ontario, and a full annual cycle inte-grated population model, we examined the influence of environmental conditions and density on the population growth rate of Canada jays (Perisoreus canadensis), a resi-dent boreal passerine that relies on perishable cached food for over-winter survival and late-winter breeding. Our results demonstrate that fall environmental variables, most notably the number of freeze–thaw events, carried over to influence late-winter fecundity, which, in turn, was the main vital rate driving population growth. These re-sults are consistent with the hypothesis that warmer and more variable fall conditions accelerate the degradation of perishable stored food that is relied upon for successful reproduction. Future warming during the fall and winter may compromise the viability of cached food that requires consistent subzero temperatures for effective preserva-tion, potentially exacerbating climate-driven carry-over effects that impact long-term population dynamics