Leadership Behavior in Relation to Dominance and
Reproductive Status in Gray Wolves, Canis lupus

The study was conducted on the 100 000-ha Northern Range of Yellowstone National Park in northwestern Wyoming and adjacent Montana (Houston 1982). Elevation ranges from 1610 to 3462 m (Yellowstone National Park 1997). The climate of the study area is characterized by long cold winters and short cool summers (Yellowstone National Park 1997). Forests in the area consist primarily of lodgepole pine (Pinus contorta) and Douglas-fir (Pseudotsuga menziezii), but there are extensive open habitats that include mesic meadow, mesic shrub-meadow, riparian areas, grassland, sage grassland, and road (Weaver 1978; Gese and Grothe 1995). Our observations were made in open sagebrush-grassland and semiopen Douglas-fir steppe in the northeastern portion of the Park. The average temperature was −12°C during data collection in early winter (November-December) and −10°C during late winter (March). Although elk (Cervus elapus) were the primary prey of wolves during this study (Smith et al. 1999), other potential prey in the area included mule deer (Odocoileus hemionus), moose (Alces alces), bison (Bison bison), bighorn sheep (Ovis canadensis), pronghorn antelope (Antilocapra americana), and mountain goat (Oreamnos americanus). Sympatric carnivores were primarily coyote (Canis latrans), mountain lion (Puma concolor), red fox (Vulpes vulpes), grizzly bear (Ursus arctos), and black bear (Ursus americanus). Many of the wolves we observed were originally translocated to Yellowstone National Park from British Columbia and Alberta, then held in acclimation pens for 10 weeks before being released in the Park (Phillips and Smith 1996).