Traditional prey preference models use a coarse species-specific prey body mass of three-quarters of adult female body mass, assumed to reflect the average mass across the prey population. This ignores demographic-specific prey preferences, potentially biasing estimates of preferred prey sizes. We refined prey selection models for two model predators with contrasting hunting strategies, by including seasonal consumption and availability of prey demographic classes. We predicted that cheetahs would select for smaller neonate and juvenile prey, while lions would select for