Squirrel, encountered under the same circumstances, soon became accustomed to the camera so that the photographer, himself at some little distance, was able to release the shutter when the lens of the camera was less than thirty inches from the animal photographed. Compared with this, the Digger Squirrels proved exceedingly wary, refusing to show more than their heads even though the camera was disguised and placed six feet distant. The confidence of the Digger Squirrel could no doubt be gained, given sufficient time; but when an approach was attempted by the methods that had proven successful with the other squirrels the results were nil. It looks as though the reactions of the Digger Squirrel had been adjusted to meet that category of enemies which lie in wait at jumping distance.
Fig. 5. Typical "hog-wallow" land showing trail and burrows of the California Ground Squirrel. Photographed ten miles north of Fresno, April 10, 1911.
Ground squirrels traveling to and fro, between their holes and their feeding grounds frequently traverse the same courses until regular radiating trails 2½ or 3 inches wide are worn through the grass (see fig. 5). This is particularly well seen on many hillsides, and on the rolling "hog-wallow" lands along the eastern side of the San Joaquin Valley, where, in the fall, when the grass and weeds are dry, the trails show most distinctly. In the spring, when the new growth is just appearing, the trails are still conspicuous, as the vegetation is slower in starting there than in the adjacent unbeaten tracts. Soon, however, the trails are entirely obliterated, save as the animals renew them by further use.
In foraging for seed-pods, grain, or fruits, the ground squirrel does not usually eat the food on the spot where it is gathered, but he stuffs it into his capacious cheek pouches (see fig. 13) or else, if it is too large for this, carries it in his mouth nipped between the incisor teeth. He then repairs to some point of vantage such as a rock pile or to the mound at the entrance of the burrow. Here he proceeds to hull and devour the food at leisure and at the same time is near enough to shelter so that he can quickly duck in should an enemy suddenly appear at
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