This study examines subsistence remains from Late Prehistoric period sites on and adjacent to the Edwards Plateau. Archaeologists have argued that a shift from generalized hunting and gathering to big game hunting occurred during the Toyah phase, the latter part of the Late Prehistoric. The shift signals a move to high return big game resources and implies the existence of environmental conditions that can support them. Assessment of subsistence remains using the diet-breadth model does not support the argument that diet-breadth narrowed with a focus on big game hunting in the Toyah phase. The sites reviewed in the current study exhibit wide variation in subsistence remains from very low-ranked plant foods to high-ranked big game resources. The data are better explained by a change in mobility strategies responding to a variable and risky environment. These strategies, particularly bulk processing plant and animal resources at special activity sites, leave very visible archaeological signatures that can be mistaken for long-term changes in diet-breadth. Therefore, the economy was not dominated by hunting, the environment of the Edwards Plateau was not conducive to supporting large populations of bison or other large game, and subsistence remained based on a broad suite of plant and animal resources.