GBA¥ SQUIRREL 201 



A female Gray Squirrel watched in Yosemite Valley on May 19, 1919, 

 was spending much of her time on the ground seeking out acorns buried 

 (presumably by the same animal) during the preceding autumn. The 

 squirrel went along hesitatingly, with her nose close to the ground, moving 

 this way and that, as though she were smelling for the nuts. When she 

 found a promising prospect she would whisk aside the winter's deposit 

 of pine needles with her forefeet and then dig rapidly down 2 inches or 

 less, pulling the earth toward her and heaping it beneath her chest. If 

 an acorn was found, the squirrel would dislodge it with her teeth and then 

 and there, sitting back on her haunches, immediately shell out and eat 

 the nut. In one instance an acorn which was dug up was buried again 

 in a new place ten feet away. The squirrel tamped the earth down over 

 it with her nose and forepaws and then raked pine needles over the place. 

 Only about one in three of the places which were prospected yielded acorns ; 

 so we may infer that these animals are not infallible. It would seem that 

 the sense of smell must be relied upon to find these ' planted ' acorns. After 

 the winter's snow, rain, and wind, with much movement of oak leaves and 

 pine needles on the surface of the ground, accurate memory of the sites 

 is apparently out of the question. Furthermore, one of the acorns which 

 the squirrel dug up and replanted, and which one of us later examined, 

 had a distinctly sour odor, clearly perceptible to our gross sense of smell. 



In this particular instance we have support for the belief that instinct 

 rather than reason controls the squirrel's food-getting activities. There 

 was no real need for this squirrel's activity, because there had been an 

 extremely abundant crop of acorns on the black oaks during the preceding 

 winter and acorns were still to be found on the ground in large numbers. 

 The squirrel could have found much more forage in a given period of time 

 by moving a short distance into the oak forest; yet she remained and 

 foraged beneath the pines in the instinctive manner which serves her in 

 a season of shortage. 



In Yosemite Valley on October 8, 1914, a large 'bracket' fungus grow- 

 ing at a height of 15 feet on the trunk of a black oak showed many tooth 

 marks of Gray Squirrels (and possibly some made by Flying Squirrels) ; 

 there were also many 'crumbs' on the ground beneath. The tooth marks 

 were mostly on the under surface ; the top surface was tough and leathery. 

 The free edge had been gnawed literally to shreds and the indication was 

 that most of the mass had been eaten away. When found, the base against 

 the tree was 9 inches (230 mm.) wide and 3I/2 inches (90 mm.) high, and 

 the mass projected out 5 inches (120 mm.) from the trunk. The taste, to 

 the naturalist 's tongue, was not unpleasant, somewhat like raw mushrooms, 

 but rather woody. At other times gray squirrels were observed digging 

 a tough kind of fungus out of the ground. 



