Wildlife and Rescue on Instagram: "Wolves were eradicated from Yellowstone National Park by the 1920s, mainly because people saw them as a threat to livestock and game animals. Without wolves, the ecosystem became unbalanced. Elk populations grew rapidly and overgrazed trees and shrubs, which meant fewer willow and aspen trees for beavers, birds, and other species. This lack of vegetation also left riverbanks bare and unstable, changing the natural flow of streams. In 1995, wolves were reintrodu