Biologists To Release Yellowstone National Park Wolf Pack

On Monday, biologists plan to release a pack of five wolves from their pen in Yellowstone National Park, as part of the project to rebuild a wolf population in the Yellowstone ecosystem.

The Soda Butte pack consists of two adults, a yearling female and two pups. The pups were born in April on a ranch near Nye, after the older wolves wandered from the park and established a den on the private property.

Managers of the wolf project eventually returned the pack to the park, after some residents of the Nye area expressed discomfort with the animals’ presence, particularly after a dog was killed.

In the future, wolves that wander will not be returned to the park, said Mike Phillips, a wolf biologist. As the wolves multiply, their territory should expand, he said.

In anticipation of their release, the pups were tranquilized on Thursday and removed from the pen they shared with the three other wolves. Biologists vaccinated the pack.