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Grassland bird populations have declined faster than any other avian guild in North America during the past 40 years. In northern Montana, four species are experiencing dramatic population declines, Baird�s Sparrow (Ammodramus bairdii), Sprague�s Pipit (Anthus spragueii), Chestnut-collared Longspur (Calcarius ornatus), and McCown�s Longspur (Rynchophanes mccownii). All four of these birds are classified as species of concern in Montana. The primary threat to grassland birds is habitat degradation and fragmentation due to conversion of native prairie for farmland, energy development, and exurban development. Most of the remaining native prairie is maintained for cattle grazing, either on private ranches or on public land leased to private ranchers. Informed management of native prairie has the potential to maximize habitat value for vulnerable species. However, the necessary information needed to design effective management strategies are lacking. In 2017, we began a 2-year study to evaluate relationships between avian abundance, nest density, and nest survival at management focused spatial scales and their relationships to local and pasture-level vegetative conditions. We conducted 150 fixed-radius point-counts at 50 randomly-selected 9 ha plots (3 visits per site) with similar forage productivity during 21 �� 26 May to estimate local abundance. We subsequently conducted 2�3 nest searches of each plot using standard rope-dragging techniques to estimate nest density. Discovered nests were monitored to estimate daily nest survival. We modeled these parameters as functions of multi-scale habitat conditions including visual obstruction, biomass, and percent cover and heights of different vegetative classes. We will present information from our first year of study evaluating: the effects of local and pasture-level vegetation conditions on nest survival for our focal species, the effects of vegetation composition and structure on bird abundance and nest density, and the functional relationships among abundance, nest density, and nest survival of sentinel grassland birds in northern mixed-grass prairie habitat.