BEARS 65 



arrival of the first heavy storm of the winter (usually in December or 

 January) it seeks a warm and sheltered cave among the rocks or some other 

 similar situation and there sleeps during the time that heavy snow covers 

 the ground outside. It remains in hibernation until the middle or end of 

 April, when the bulk of the snow at middle altitudes has melted. In 1920 

 the first bear tracks noted in the lower part of Yosemite Valley were seen 

 on March 18. Those individuals which live below the limit of heavy snow 

 (about 3500 feet in this latitude) are prone to come out and forage actively 

 abroad from time to time throughout the winter. Some residents of the 

 region have suggested to us that the bears living in the higher mountains 

 perform a limited altitudinal migration, but we have no definite informa- 

 tion on this point. 



The dens used by the bears in the Yosemite region are chiefly such as 

 are found in the heaps of talus and slide rock which abound in various 

 parts of the Park. The bears which feed at the garbage pits in the Yosemite 

 Valley are thought to have their dens in the rock slides under Cathedral 

 Spires, for in this vicinity a trail leads from the pits toward the wall of 

 the Valley. 



When the Black Bears go into hibernation in the early winter they are 

 very fat, but most of this excess fat is used up during the long winter sleep. 

 When they first emerge in the spring they are not very active and little 

 is to be seen of them for some time. Soon, however, they begin to eat again, 

 sparingly at first, and then more greedily, until in summer and fall they 

 amply justify the oft-made remark, ' ' hungry as a bear. ' ' As the summer 

 wanes their search for food leads them farther and farther afield, their 

 tracks and sign become more and more in evidence, and they themselves 

 are more frequently seen by visitors. During the autumn they must eat 

 not only to sustain their bodies from day to day, but enough in addition 

 to provide another supply of fat to carry them through the following 

 winter. This fat is especially important in the case of the females, as 

 their cubs are born in midwinter and the only source of nourishment for 

 the young until they emerge in the spring is the milk elaborated in the 

 bodies of the mothers from this reserve of fat. 



Under original conditions of life the Black Bear is active in the daytime 

 as well as at night, but most of the depredations which it commits in the 

 vicinitj^ of camps and buildings are done under the cover of darkness. The 

 Black Bear is an adept at climbing, from the day that it first emerges from 

 the den, a young cub in the care of its mother, on throughout its entire life. 

 When frightened it often seeks safety by ascending the nearest tree strong 

 enough to support it. When trailed by dogs it finally evades them in this 

 manner. 



