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Explaining the interaction between grazing management and wildlife on rangelands requires isolating effects within a complex biophysical system. Variables such as precipitation, range site productivity, and soils are further confounded by human decision making in real world grazing operations. In South Texas, northern bobwhites (Colinus virginianus) commonly occur on lands where grazing and hunting are integral parts of the ranch�s viability and longevity.� A large-scale monitoring project was developed to assess the impact of different cattle grazing regimes on bobwhite density and vegetation structure over� 4 treatment pastures (18,989 acres; continuous and rotations at medium and low stocking rates) and 3 reference sites (10,789 acres) on East Foundation lands in Jim Hogg County, Texas. Our primary objectives are to compare (1) bobwhite densities and (2) vegetation parameters both before and during-treatment on all sites, December 2014�2017.�We estimated pre-grazing bobwhite density using line-transect distance sampling via helicopter between December 2014 and 2015. After 2 years of deferment, cattle were stocked on treatment sites in late December 2015. We obtained measurements of vegetation structure, forage standing crop, and grazing intensity during the autumn and summer of 2014?2016. Bobwhite density estimates pooled across the treatments areas increased by 175% from 2014 (0.20 quail per acre; 95% CI = 0.15�0.26) to 2015 (0.55; 95% CI = 0.47�0.64). Density estimates within years among the 4 treatments were similar. On the reference sites, bobwhite density increased by 35% from 2014 (0.22; 95% CI = 0.16�0.30) to 2015 (95% CI = 0.22�0.34). This study will aid managers in understanding how cattle grazing practices and vegetation structure interact to affect bobwhite densities on a population-wide scale.