Phenological resources are common across many ecological communities, and can strongly affect community dynamics. Recent field manipulation experiments in stream food chains found that seasonal timing and duration of terrestrial prey inputs affected the feeding behavior, growth, and maturation of fish predators, caused predator-mediated indirect effects on aquatic prey, and modified trophic-cascading effects on ecosystem processes (i.e., litter decomposition). These experiments described impacts of resource phenological changes over a few month period, but long-term impacts of continued changes in resource phenology are unknown. Here, we develop a mathematical model to extrapolate long-term predictions about the effects of changes in resource phenology from the results of field manipulation experiments. The model predicts that advanced timing generally decreases aquatic prey and litter processing and prolonged duration will either increase or decrease aquatic prey and litter processing depending on the total amount and pre-disturbed timing and duration of terrestrial prey inputs. Our modeling approach clarifies that stage-specific responses of life history processes in fish (i.e., growth, maturation, and reproduction) to phenological changes in terrestrial prey inputs mediate indirect effects on aquatic prey and litter processing. We argue that stage-specific responses of life history processes are an integral part of the mechanisms with which to predict the consequences of phenological species interactions at the community and ecosystem levels.