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Grazing by cattle affects plant morphology, phenology, and species composition, which can result in changes within invertebrate communities at broad scales.� For grassland songbirds, altered invertebrate communities may influence prey availability or foraging preferences, and ultimately affect habitat use or demography.� Although grazing represents a complex disturbance, in managed systems stocking rate and associated vegetation utilization levels can determine vegetation responses to grazing, and potentially, habitat quality for other trophic levels. �To better understand the relationship between utilization and grassland bird food habits, we examined diet composition of nestlings for four songbird species breeding in paddocks with experimentally-manipulated stocking rates in a Pacific Northwest bunchgrass prairie in northeastern Oregon.� We compared nestling diet composition with invertebrate abundance in paddocks to examine the effect of utilization rates on dietary preferences of breeding birds.� Moths and butterflies comprised the largest proportion of prey in nestling diets (31%) followed by short-horned grasshoppers (28%) and spiders (20%).� We observed variable preferences across invertebrate taxa, with strongest preference for moths and butterflies.� Preference for only two invertebrate taxa varied as a function of utilization rate, and only in the first year of our study: moths and butterflies were preferred at low utilization rates and avoided at high utilization rates, and spiders were more strongly avoided at moderate versus high utilization.� When compared to patterns of invertebrate abundance at the paddock-level, the lack of strong patterns of preference with increasing utilization suggest that adult birds may be able to compensate for altered food abundance by adjusting foraging strategies.� However, this compensation may still come at a cost to nestlings if more time is devoted to foraging for specific prey by adults, thereby allowing less time for nest defense, or negatively affecting total volume of prey delivered to nestlings.� Implications for grazing management will be discussed.