This complex project has increased the numbers of beavers and other smaller animals within the park by controlling the elk population, which became too large for its prey to thrive when the last wolves in the park's ecosystem died in the 1930s.
Efforts to reintroduce gray wolves into Yellowstone National Park have been successful enough to alter its entire ecosystem for the better. This complex project has increased the numbers of beavers and other smaller animals within the park by controlling the elk population, which became too large for its prey to thrive when the last wolves in the park's ecosystem died in the 1930s.