The reintroduction of wolves to the park was highly debated for many years, but after careful planning they were released into the park.
Wolves exhibit social, hierarchial, competitive, and territorial tendencies.
They generally travel in packs with eight members or less. However, in the summer of 1998 one pack of wolves in Yellowstone had grown to 16 members. The social order of the pack is the alpha pair, being the most important members, the beta wolf, the second most important, down to the omega wolf, being the least important member of the pack. The social order of the wolves can change due to sexual maturity, old age, illness, or death. If one of the alpha pair dies, the beta wolf will take its place.