Northern Prairie Wildlife Research Center
The only consistent demonstration of rank in natural packs is the animals' postures during social interaction. Dominant wolves assume the classic canid standing posture with tail up at least horizontally, and subordinate or submissive individuals lower themselves and "cringe" (Darwin 1877). In fact, submission itself may be as important as dominance in terms of promoting friendly relations or reducing social distance.
Schenkel (1967), who promoted the importance of submission, recognized two main types, active and passive. He believed that active submission is derived from food-begging behavior, and I find active submission and food-begging indistinguishable. The begging or submissive wolf approaches another wolf excitedly, wagging the tail, lowering the ears, and "licking up" to the other wolf. The other wolf may or may not regurgitate food, depending on circumstances (Mech et al. 1999). In passive submission, the submissive wolf rolls over on its side or back, and the dominant wolf sniffs its groin or genitals (Schenkel 1967). Active submission was more common in the Ellesmere Island pack.
In that pack, all members, including the breeding female, submitted posturally to the breeding male, both actively and passively (Schenkel 1967). The yearlings and 2-year-old wolves and one old post-reproductive female submitted to both breeders. These rules held regardless of pack composition: breeding pair or breeding pair with pups (Table 1); breeding pair with yearlings (Table 2); breeding pair with yearlings and pups (Table 3); breeding pair with pups and 2-year-old auxiliaries (Table 4), or breeding pair with pups and post-reproductive female (Table 5).
| Table 1. Dominance interactions, i.e., the number of times individual wolves dominated others or were submitted to, during summer between breeders in the Ellesmere Island wolf pack when no auxiliaries were present. | |||
| Year | Breeding male |
Breeding female |
Pups present? |
| 1992 | 9 | 0 | Yes |
| 1996 | 21 | 0 | Yes |
| 1998 | 4 | 0 | No |
| Note: Interactions were primarily active submissions, but three cases of passive submission are included (Schenkel 1967); they do not include "standing over" or interactions involving food, except for "food-begging". | |||
| Table 2. Dominance interactions, i.e., the number of times individual wolves dominated others or were submitted to, among breeders and yearlings in the Ellesmere Island wolf pack in 1993 (no pups were present, and parents were as shown in Table 1). | ||||||
| Male parent |
Female parent |
Female yearling 1 |
Male yearling |
Female yearling 2 |
Total | |
| Male parent | -- | 0 | 0 | 0 | 0 | 0 |
| Female parent | 3 | -- | 0 | 0 | 0 | 3 |
| Yearling female 1 | 3 | 2 | -- | 0 | 4 | 9 |
| Yearling male | 4 | 3 | 0 | -- | 0 | 7 |
| Yearling female 2 | 4 | 3 | 0 | 0 | -- | 7 |
| Yearling? | 3 | 2 | 0 | 0 | 0 | 5 |
| Total | 17a | 10a | 0 | 0 | 4 | 31 |
| Note: Interactions do
not include "standing over" or involve food, except for "food-begging."
" aFor male parent versus female parent,
=0.94, P = 0.33, df = 1. |
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| Table 3. Dominance interactions, i.e., the number of times individual wolves dominated others or were submitted to, among breeders and yearlings in the Ellesmere Island wolf pack in 1988 (pups present and breeding male was the same, as in 1990-1996). | |||||
| Male parent |
Female parent |
Male yearling |
Female yearling |
Total | |
| Male parent | | 0 | 0 | 0 | 0 |
| Female parent | 2 | | 1 | 0 | 3 |
| Male yearling | 8a | 4 | | 1 | 13 |
| Female yearling | 5b | 9 | 0 | | 14 |
| Total | 15 | 13 | 1 | 1 | 30 |
| Note: Interactions do not include
"standing over" or involve food, except for "food-begging." aIncludes one short bout of five submissions. bIncludes one short bout of four submissions. |
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| Table 4. Dominance interactions, i.e., the number of times individual wolves dominated others or were submitted to, among breeders and 2-year-old wolvesa in the Ellesmere Island wolf pack in 1994 (pups were present, and parents were the same as is shown in Tables 1 and 2). | |||||
| Male parent |
Female parent |
Two-year- old female |
Two-year- old male |
Total | |
| Male parent | | 0 | 0 | 0 | 0 |
| Female parent | 13 | | 2b | 2 | 17 |
| Two-year-old female | 8 | 9 | | 4 | 21 |
| Two- year-old male | 4 | 0 | 0 | | 4 |
| Total | 25c | 9c | 2 | 6 | 42c |
| Note: Interactions do not include
"standing over" or involve food, except for "food-begging." aThese are the yearlings in Table 2. bThe female parent dominated the 2-year-old female for 15 min at one of these times. Another time, when it was unclear whether the female parent or 2-year-old female dominated, is not included. cFor male parent versus female parent, = 3.99,
P = 0.05. |
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| Table 5. Dominance interactions, i.e., the number of times individual wolves dominated others or were submitted to, among breeders and a post-reproductive female in the Ellesmere Island wolf pack in the summers of 1990 and 1991 (pups were present and the male parent was the same as in all other years in the study except 1998). | |||||
| Male parent |
Female parenta |
Post-reproductive femaleb |
Total | ||
| Male parent | | 1c | 0 | 0 | |
| Female parenta | 35 | | 1 | 36 | |
| Post-reproductive femaleb | 26 | 17 | | 43 | |
| Total | 61 | 18 | 1 | 80d | |
| Note: Interactions do not include
"standing over" or involve food, except for "food-begging." aYearling female in 1988 (Table 1) and female parent in 1990-1996. bFemale parent in 1988 and 1989 (Table 1). cMale deferred when approaching a female and young pups in a den. d |
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That these submission rules help promote friendly relations was demonstrated dramatically by an observation I made on 22 June 1991. A post-reproductive female returned to the den area with a very dried hare carcass, more an interesting distraction than food. Instead of bringing the dried hare directly to the pups, the old female went out of her way to take it submissively to the breeding male, which instantly snatched it from her. He refused entreaties by both that female and even the breeding female and chewed it himself for 20-30 min.
The only other general dominance rules I discerned involved scent-marking and food ownership and transfer. With scent-marking, both breeding male and female mark, but subordinates do not unless vying for dominance (Packard 1989; Asa et al. 1990), and I have seen no exceptions. Regarding food ownership and transfer, when the pack contained pups or yearlings, the breeding male I observed either regurgitated or dropped food to his mate or allowed her to snatch it from him or he delivered it directly to his offspring.
Aside from these food deliveries, there appeared to be an ownership zone (Mech 1970) around the mouth of each wolf, and regardless of the rank of a challenger, the owner tried to retain the food it possessed, as Lockwood (1979) also found with captive wolves. Wolves of any rank could try to steal food from another of any rank, but every wolf defended its food (Table 6). Generally, dominant wolves seemed to succeed more at stealing food, but sample size was too small for a definite conclusion to be drawn.
| Table 6. Observed attempts to defend food from packmatesa in the Ellesmere Island wolf pack. | |||
| Date | Possessor of food | Challenger | Result |
| 1988-06-26 | Pups/yearling femaleb | Breeding female | Succeeded |
| 1988-07-01 | Yearling female Pupc |
Breeding female Yearling male |
Succeeded Failed |
| 1988-07-05 | Yearling female | Breeding female | Succeeded |
| 1988-07-27 | Yearling female Breeding male Breeding male |
Yearling male Yearling female Yearling male |
Failed Failed Succeeded |
| 1990-08-05 | Breeding male | Post-reproductive female | Failed |
| 1991-06-22 | Post-reproductive female | Breeding male | Succeeded |
| 1993-07-11 | Yearling female | Yearling female | Failed |
| 1994-07-16 | Pups and yearling male | Yearling female | Failed |
| 1996-07-15 | Pups/breeding female | Breeding maled | Succeeded |
| 1998-07-07 | Breeding female | Breeding male | Failed |
| aDoes not include the
breeding female taking food from the breeding male. bYearling female had brought food to the pups and snapped at the breeding female when she stole it. cYearling female, who had brought a hare, stood guard near the pup. dBreeding female failed to stop the breeding male. |
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Two other behaviors among pack members could have been dominance-related, although data were insufficient to be certain. They were "standing over" and "hugging" (L.D. Mech, see footnote). In "standing over," one wolf would stand over (Schenkel 1947) a lying wolf, positioning its groin above the nose of the lying wolf. Sometimes the lying wolf sniffed at the groin or genitals of the standing wolf.
Schenkel (1947) saw "standing over" only during "peaceful" times and did not seem to consider it dominance-related. In the case of hugging, my sample size (5) was insufficient to determine whether it was dominance-related (L.D. Mech, see footnote).
The above dominance rules, which involve a natural age-based order with the current breeders at the top and offspring or non-breeders subordinate, are so automatic that they are seldom contested. In that respect, the social interactions among members of natural wolf packs are much calmer and more peaceful than Schenkel (1947) and Zimen (1982) described for captive wolves, as Clark (1971) also noted. Similarly, pups defer to adults and older siblings in the same automatic, peaceful way. When or whether a rank order develops among pups is in dispute (cf. Zimen 1975 and Fox and Andrews 1973; Haber 1977), and I cannot shed any light on that issue. Even among yearlings and 2-year-olds there were few rank displays (Tables 2-5).
It is conceivable that social tensions would mount during the breeding season (Schenkel 1947), but the fact that most natural packs contain only a single breeding pair would preclude such tension. The earliest age at which wild wolves are known to breed is 22 months (Seal et al. 1979), and some individuals are not sexually mature until they are at least 4 years old (Haber 1977; Mech and Seal 1987). Because most wolves disperse before 2 years of age, and almost all before 3 years of age (Mech 1987; Gese and Mech 1991; Mech et al. 1998), there would be no source of sexual competition within most packs.
Thus, only in the relatively few packs with multiple breeders might there be intense rivalries such as those Haber (1977) reported during the breeding season in his unusual pack. On the other hand, at least some of the difference in reported "hostility" might be due to different viewpoints of the observers. I occasionally saw intense "pinning" of a 2-year-old female by her mother in summer 1994 that some might label "hostile." However, to me this behavior appeared to be merely the type of interaction I observed between the mother and an errant pup she could not control. In any case, these types of interaction were uncommon during my study.
As for high-ranking animals asserting any practical control over subordinates, the nature of the interaction is highly conditional. For example, with large prey such as adult moose (Alces alces), pack members of all ranks (ages) gather around a carcass and feed simultaneously, with no rank privilege apparent (Mech 1966; Haber 1977); however, if the prey is smaller, like a musk ox calf, dominant animals (breeders) may feed first and control when subordinates feed (Mech 1988; National Geographic 1988).
Similarly, pups are subordinate to both parents and to older siblings, yet they are fed preferentially by the parents, and even by their older (dominant) siblings (Mech et al. 1999). On the other hand, parents both dominate older offspring and restrict their food intake when food is scarce, feeding pups instead. Thus, the most practical effect of social dominance is to allow the dominant individual the choice of to whom to allot food.
The only other rank privilege I am aware of in natural situations is that high-ranking pups are more assertive in competing for food deliveries by adults and sometimes accompany adults on foraging trips at an earlier age than do subordinates (Haber 1977).
L.D. Mech. "Standing over" and "hugging" in wild wolves. Submitted for publication.