As a result of the combined impacts of shifts in immigration policies and increased Homeland Security, the United States-Mexico border region has become increasingly degraded in environmentally protected areas. Such activities include migrant and smuggler traffic as well as a corresponding influx of Border Patrol agents, vehicles, fence, and wall construction and high-tech security systems. Disparate parties are quick to assign blame: on the one hand, "dirty Mexicans" are identified as corrupting a pristine environment as they leave behind garbage and human waste. On the other hand, Border Patrol is often identified as a major perpetrator of environmental damage at the border, driving off-road and subjecting the fragile desert landscape to fence and wall construction and security-related traffic. In this paper, based on ethnographic fieldwork conducted between 2007 and 2009 at Cabeza Prieta National Wildlife Refuge, adjacent to the United States-Mexico border, I discuss the ways in which different perceptions of degradation are linked to broader social and political norms and can, at times, even reinforce negative ethnic stereotypes regarding the threat and impact of Mexican-origin immigration.