Northern Prairie Wildlife Research Center
Most research on the social dynamics of wolf packs, however, has been conducted on wolves in captivity. These captive packs were usually composed of an assortment of wolves from various sources placed together and allowed to breed at will (Schenkel 1947; Rabb et al. 1967; Zimen 1975, 1982). This approach apparently reflected the view that in the wild, "pack formation starts with the beginning of winter" (Schenkel 1947), implying some sort of annual assembling of independent wolves. (Schenkel did consider the possibility that the pack was a family, as Murie (1944) had already reported, but only in a footnote.)
In captive packs, the unacquainted wolves formed dominance hierarchies featuring alpha, beta, omega animals, etc. With such assemblages, these dominance labels were probably appropriate, for most species thrown together in captivity would usually so arrange themselves.
In nature, however, the wolf pack is not such an assemblage. Rather, it is usually a family (Murie 1944; Young and Goldman 1944; Mech 1970, 1988; Clark 1971; Haber 1977) including a breeding pair and their offspring of the previous 1-3 years, or sometimes two or three such families (Murie 1944; Haber 1977; Mech et al. 1998).
Occasionally an unrelated wolf is adopted into a pack (Van Ballenberghe 1983; Lehman et al. 1992; Mech et al. 1998), or a relative of one of the breeders is included (Mech and Nelson 1990), or a dead parent is replaced by an outside wolf (Rothman and Mech 1979; Fritts and Mech 1981) and an offspring of opposite sex from the newcomer may then replace its parent and breed with the stepparent (Fritts and Mech 1981; Mech and Hertel 1983).
Nevertheless, these variations are exceptions, and the pack, even in these situations, consists of a pair of breeders and their young offspring (Mech 1970; Rothman and Mech 1979; Fritts and Mech 1981; Mech and Hertel 1983; Peterson et al. 1984). The pack functions as a unit year-round (Mech 1970, 1988, 1995b).
As offspring begin to mature, they disperse from the pack as young as 9 months of age (Fritts and Mech 1981; Messier 1985; Mech 1987; Fuller 1989; Gese and Mech 1991). Most disperse when 1-2 years old, and few remain beyond 3 years (Mech et al. 1998). Thus, young members constitute a temporary portion of most packs, and the only long-term members are the breeding pair. In contrast, captive packs often include members forced to remain together for many years (Rabb et al. 1967; Zimen 1982; Fentress et al. 1987).
Attempting to apply information about the behavior of assemblages of unrelated captive wolves to the familial structure of natural packs has resulted in considerable confusion. Such an approach is analogous to trying to draw inferences about human family dynamics by studying humans in refugee camps. The concept of the alpha wolf as a "top dog" ruling a group of similar-aged compatriots (Schenkel 1947; Rabb et al. 1967; Fox 1971a; Zimen 1975, 1982; Lockwood 1979; van Hooff et al. 1987) is particularly misleading.
Because wolves have been persecuted for so long (Young and Goldman 1944), they have been difficult to study in the wild (Mech 1974) and therefore information about the social interactions among free-living wolf pack members has accumulated slowly. Little is known about the interactions between breeding males and breeding females under natural conditions, and about the role of each in the pack and how dominance relates to these relationships.
A few people have observed the social behavior of wild wolves around dens, but Murie (1944) gave an anecdotal account, Clark (1971), in an unpublished thesis, presented only a quantified summary of the pack's hierarchical relationships, and Haber (1977) described his interpretation of a pack's social hierarchy but gave no supporting evidence. Thus, no one has yet quantified the hierarchical relationships in a wild wolf pack.
Here I attempt to clarify the natural wolf-pack social order and to advance our knowledge of wolf-pack social dynamics by discussing the alpha concept and social dominance and by presenting information on the dominance relationships among members in free-living packs.