Sheep may not have the aggression to protect themselves, but llamas sure do, and farmers have been utilizing their charging ways for years to keep coyotes away. A 2003 survey by Iowa State University found that 50% of llama-guarded flocks had a 100% reduction in attacks since they were put to use. It’s believed that the family of camelids that llamas belong to were once stalked by dogs, which brought about an aggressive reaction to predators.