Since January, more than 500 bison at Yellowstone National Park have been culled as a way to control the animal’s population, the largest number in years. The slaughter comes as part of a 15-year-old agreement signed by both federal and state agencies that often results in bison being chased onto trucks and sent to slaughterhouses. Farmers in the state don’t want the bison grazing on their fields and have concerns about the animals carrying a bacterial disease that they find a threat to their cattle. While brucellosis infection rates among Yellowstone’s wild herds are high, there have been no confirmed cases of cattle contracting the disease from bison wandering outside the park, scientists point out,” The Washington Post reported. “Meanwhile, there is little public outcry about migrating herds of wild elk, which also carry the disease.” The current plan calls for a population limit of 3,000 individuals; however, that number could soon double. The Yellowstone bison also represent one of the greatest species-recovery stories in history—a population of 23 recovered during the past 100 years has increased to approximately 4,500 today, making them the largest population of wild bison in the world.