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MOUNT RAINIER NATURE NEWS NOTES
Vol. II May 1st, 1925 No. 20


BEARS DENS

We have estimated that between two and three hundred bear make their home in the National Park. About Longmire Springs in the Nisqually Valley they are usually quite abundant but the other day we saw the first bear that any one had seen for four months. During the summer they are about almost every day but during the winter they are never seen.

The explanation is interesting. Bears, in common with several other animals, solve the numerous problems resulting from the cold, stormy, winter season by absolutely ignoring them. At the coming of cold weather they select a comfortable, well-protected and concealed den and deliberately place themselves in cold storage for the winter. The comparison is not far-fetched for literally the animals are in natural cold storage warehouses and are covered for the greater part of the time by several feet of snow and ice. During the deep, lethargic sleep, known as "hibernation" the bodily temperature drops far below the normal and the heart action becomes extremely slow and slight. Certain animals, such as the ground squirrels actually become rigid during the coldest weather.

At any time during hibernation the dormant may be restored to normal activity by placing them for a time in a warm temperature. When again put in the cold they at once return to sleep proving that the duration of hibernation is directly dependent upon temperature. During periods of unusual warmth bears and other animals sometimes leave their dens for a time only to return at the first change of weather. Chipmunks appear and become extremely active for a few hours on warm days in early spring but do not come out for the summer until late in the spring. I have known wild bears to be dragged from their dens in cold weather and handled with perfect safety. They seem quite unconscious and make no movements. Upon being moved about they stretch and yawn and become sufficiently awakened to try to crawl back in the den. If left outside they manage to make their way into the den again.

During the season of wild berries (in the fall) bears find ample food and often become excessively fat. It was long considered that this excess of fat was gradually absorbed during the long winter sleep and thus served in the place of food to sustain life but it is now well known that bears usually appear in the spring in very good condition and in numerous cases - even though it was a mother with young - I have known them to be quite fat after four months of fasting. As a matter of fact, the bodily functions during this dormant period are practically suspended and the animal is literally in cold storage. During the period of great activity in the early spring this supply of fat is often used up as food is scarce at that time of year. Apparently fat is stored up for the following summer rather than for the winters' inactivity. In the Park the bears normally den-up as soon as the first heavy snows come in the early winter. This is usually late in November but may be as late as Christmas. Sometimes by the middle of March but often not until April, the weather becomes sufficiently mild to bring them out.

Occasionally the bears that have frequented the high valleys find dens under dense matted trees or in crevices in the rocks and are buried for the winter under from ten to thirty feet of snow but usually they migrate to the lower valleys where the snow is not so heavy and comfortable hollow trees or logs may be found.

Recently Ranger Macy discovered a den in the hollow butt of a six-foot cedar. It was long the Nisqually River at about 2500 feet elevation. The hollow tree stood on a small knowl in one of the densest thickets of second-growth hemlocks I have ever seen. It was not typical bear country, the entire valley being filled with a dense growth of trees but certainly it was well protected and concealed. Bruin was not at home when we called but there was no question that the den had been occupied as the bed of decayed wood and small twigs had not been disturbed and the claw and teeth marks of a large bear were quite distinct in numerous places where the occupant had enlarged his doorway and bed chamber.

There are two other dens in the district that we have known the location of for some time. One is in a small cave at about 2300 feet elevation in a rocky ledge directly above the Park Entrance and the other is in the hollow base of another tree, a gigantic cedar standing at about 3800 feet elevation near Round Pass on the Wonderland Trail.

This den is a veritable bear palace with three apartments. It is large enough to comfortably house several bears and it is likely that it is used at times by more than one individual as it is common practice for the half-grown cubs to den-up the first winter with their mother. Last fall when I visited this treehouse it was evidently in use as the form marks of the bears body could be distinctly seen in the soft bed of moss and decayed wood. Recently when we visited the site again the entrance was covered with at least seven feet of densely-packed snow. It is likely that a bear would have trouble in making an early exit from such a place even if it so desired.

The tree stands in the open woods on a steep slope not far from the alpine meadows of Emerald Ridge. It is a Western Red Cedar fully ten feet in diameter at the base with an opening on the upper side about three feet high and twenty inches wide. This opens into a small compartment or ante-room from which a similar door opens into the main cavity. Two men may stand and move about with comfort in this room. Beyond and at a somewhat lower level another cavity, amply large enough to house a full-grown bear has been excavated in and beneath a protuding root. The decayed wood from above and about the sides has been clawed down to enlarge the den and has been utilized as a carpet. Dry moss and small twigs have been carried in for a bed. Always when I have visited the den it has been scrupulously clean and in better order than many a human dwelling I have seen.

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19-Feb-2001