A similar comparison between our observations from 1967 and those from 1968-69 (table 1) shows no significant difference between these years, so it appears that the density of wolves in our area has remained about the same over the period of three winters. This agrees with the results of several other studies summarized by Mech (1970) in which wolf populations unaffected by man have been found to remain relatively stable from year to year. DISCUSSION AND CONCLUSIONS The movements, behavior, and ecology of the wolves in our study area during winter are variable, and are influenced considerably by snow conditions. This may explain the fact that in late February 1969 wolves 1051, 1053, and 1055 suddenly extended their travels and range (fig. F-34 and table 4). However, increased travel may have resulted from other factors. For one thing, the wolves apparently did not need to spend so much time hunting as before. Because of the deep snow, the ability of wolves to capture deer increased, and the animals had a surplus of food. Perhaps under such conditions wolves may use more of their energy for traveling than for hunting. [Illustration: _Figure 34.--Net weekly (straight-line) distances traveled by three radiotagged wolves._] In this respect it is interesting that 1051 moved right out of his area and traveled into country that presumably was unknown to him. Wolves 1053 and 1055 each ventured into an area that was almost devoid of deer and that even had few moose in it. Without sufficient fat reserves in all these animals, it would seem disadvantageous for them to have made these travels. Evidently wolves can obtain enough food in much smaller areas than these three animals used after February. Both 1059's pack of five and 1057 lived in relatively small areas throughout the winter and seemed to survive well. Before late February, 1051, 1053, and 1055 did also. Thus some factor other than food must have influenced the movements of these three animals from late February through April. The fact that the increased movement began during the breeding season makes one suspect a relationship between the two. One possibility is that the factors increasing the hormonal flow associated with breeding in adults stimulate a hormone output in immature or subordinate individuals that causes an increase in their movements. An alternative is that the breeding behavior of resident packs involves the beginning of, or an increase in, aggression toward neighboring nonmembers. This might force the lone animals to shift about over large areas in avoidance of such aggression.