If the pack is small and there is lots to eat, the range is as small as 4 square miles. If the pack is large or food is scarce, the pack may range over 3,000 square miles. All hunting, raising of young, and other activities occur within this range. Wolves don't usually migrate instead, they travel through their range and visit most parts about every three weeks. Gray wolves communicate with each other easily.
Wolves define their territory by smell.
Every three weeks or so, they travel along their borders to mark special points a tree stump, a rock, or a fallen log. After the wolf is gone, the smell remains, alerting any other scent-oriented animal that they're crossing into a wolf pack's territory. Howling is used to communicate for two reasons. When the pack is together, howling is like a group sing it brings the pack together and generates enthusiasm for a hunt. But over long distances, howling serves another function.