The wolverine in late years seems to have become more plentiful in the park; nevertheless, it is always considered something special to see one. They range from river bottom to ridge top, are found in the woods or in open country miles beyond timber. Perhaps because of the open view, he is frequently seen on the low passes, especially on Sable Pass.
In winter the track of the far-wandering wolverine is frequently seen. In his usual gait he bounces along with back arched. Each jump usually leaves a set of three imprints; the one in front is made by a hind foot; the middle imprint is made by a hind foot falling in the track of a front foot; the rear imprint is made by the other front foot. As in the tracks of a hopping rabbit, the hind feet tend to be brought up ahead of the front feet.
The wolverine readily climbs trees. One winter, near a moose carcass, tracks in the snow showed that a wolf had chased a wolverine up a tree on two or three occasions. If the two had met in the open the threatening posture of the wolverine would, no doubt, be sufficient to discourage attack. When attacked by a dog, a wolverine has been seen to lie on its back in a defensive attitude, a position that was effective. Powerful ripping claws and jaws face the attack.
Not much quantitative information has been gathered on his food habits. I have watched him pouncing on mice and suspect that mice (voles) and lemmings are the most important items in his diet. In summer he captures ground squirrels, sometimes by doing some digging. Once I noted that he had dug out a wasp nest hidden in the ground. The calves of caribou and moose, when very young, are no doubt potential victims. But observations indicate that even a caribou can ward off an attack on the young calves. Such items would, of course, be unimportant in the wolverine’s total economy. His wide wanderings in winter would seem to be helpful in finding carrion. In rich wild country, considerable carrion probably comes his way. I have found the wolverine attending a frozen moose carcass for a number of days. When a carcass is not frozen, he carries away what he can to cache for later use.
The gestation period is said to be about 9 months. The breeding apparently takes place in summer. The fertilized eggs, after brief development, lie unattached and dormant in the uterus for several months. Some time in midwinter the eggs become attached to the wall of the uterus and the more usual development takes place. (The marten and short-tailed weasel have a similar breeding history.) Females have been found in a nursing condition in early April. Along Igloo Creek, Mr. and Mrs. Edwin C. Park watched a mother nurse two young at least two-thirds grown.
Wolverine.
According to Peter Krott, in his fascinating book about the wolverine in Europe, this fierce animal makes a friendly pet. The author, in the beginning, made a business of acquiring young wolverines for sale to zoos. Because the animal was rare and intriguing, the demand was great and the prices remunerative. But Mr. Krott and his wife became fond of the wolverines and found it ever harder to dispose of them. Soon they ceased selling them, and, instead, kept them as pets and allowed them to roam freely over wild country. Studies were made of their habits. Their wolverines might wander far and stay away for several days, but they would return at intervals.
The wolverine is at home in the McKinley wilderness. Here we have the rare opportunity of seeing him in his natural environment.