Forests, open meadows, rocky ridges, and lakes or rivers all comprise a pack's territory.
Gray wolves do, however, follow moose and caribous' elevational movements within pack territories.
They may use the same den for several years. After 1 to 2 months these natal dens are abandoned for an open area called a rendez-vous site. They tend to prey on the young, old, and sick members of ungulate populations. Occasionally gray wolves prey on domestic livestock. Organized efforts to kill all the remaining gray wolves in the western United States began in the 1860's.