NARRATOR: The grazing animals must struggle mightily in search of a few blades of grass. Many elk grow weak as winter drags on, but someone else grows strong. The wolf thrives in winter. Highly intelligent and social creatures, they often show a deep affection for one another. Their intense family ties also make them a deadly hunting unit. Once completely exterminated from the park, gray wolves were reintroduced in 1995 and have become a vital player in the park’s ecosystem.Eagerly chasing a big bull elk, the wolf is in its element in Yellowstone. But this bull didn’t earn his rank by being anyone’s fool. He finds refuge in the frigid Lamar River, where the wolves cannot follow, and aims his impressive rack at them. But another dinner awaits, as the rest of the pack announces. They’ve taken a weakened bison during the night, and there’s more than enough to go around. With such a large pack to feed, they need to hunt successfully nearly every day. .