We measured densities of Solenopsis invicta (Red Imported Fire Ant) mounds at sites occupied by Ammodramus savannarum floridanus (Florida Grasshopper Sparrow), a federally endangered subspecies, at Avon Park Air Force Range (APAFR), Kissimmee Prairie Preserve State Park (KPPSP), and Three Lakes Wildlife Management Area (TLWMA). Our objective was to compare densities of fire ant mounds among areas with active cattle grazing programs (two areas of native dry prairie habitat at APAFR and a tamed pasture at KPPSP) and areas without active grazing programs (native dry prairie habitat at KPPSP and TLWMA). Densities of fire ant mounds differed among the five areas examined and were greater in areas with active grazing programs than in areas without active grazing programs. We measured densities of fire ant mounds inside and outside of a cattle exclosure, but the total numbers detected were insufficient for analysis. We also placed bait stations inside and outside the exclosure. Fire ants were detected at 50% fewer bait stations inside the exclosure, but these differences were not significant.