One individual was surprised eight feet above the ground in a tree yucca, where he had doubtless been prospecting among the ripe pods for the seeds. He ran down the yucca trunk head foremost, with clearly audible noise of claws on rough bark. Even in this position the tail was kept appressed to the rump and was flicked in fore-and-aft direction. This ability to climb is not exceptional among individuals of this species, and is quite consistent with the general agility of the animal. Near Keeler, on the morning of September 25, 1917, six individuals were seen severally in the tops of sarcobatus bushes evidently gathering the small, fleshy leaves. At the distant approach of the observer each scurried to the ground and each had altogether disappeared by the time he had come up. At Onyx, Kern County, June 21, 1911, one was seen perched on the top of a fencepost. At Carroll Creek, near Owens Lake, September 8, 1911, several were seen at different times perched bolt upright, picket-pin fashion, on isolated boulders out on the mesa.
As a general thing Antelope Ground Squirrels do not have access to water and they live for long periods without it. Like other typically desert rodents, they can secure all the water needed in their systems by chemical elaboration of their food materials. Yet that water is sought for where available is shown by the following instances: When camped at a spring near the head of Kelso Valley, Kern County, July 8, 1911, the senior author saw an "Ammo" come without hesitation to the lowest hoofprints containing water below the spring and drink five times; each time about ten seconds were apparently occupied in lapping. At intervals the animal looked around, vibrating his tail the while with great rapidity. At least six other individuals came to drink during that day, arriving through the brush from considerable distances. One of these, observed closely, was seen to lap hurriedly and briefly eight times.
Some observations made at the same time and place bear further on the behavior of this species of ground squirrel. When one is stalked it will make a dash of ten feet or more to a near-by shrub or rock. If the observer continues to advance the squirrel disappears down a hole or under a bush, or else makes another similar dash and stops again. It then either stands on all fours with its back humped up toward the intruder and its head turned around so as to watch, or it stands upright on its haunches, turning more toward the observer. In either case the tail is held over the back and is wiggled, either antero-posteriorly or laterally. The tip of the tail, at least, shows no constant direction of movement. "When entering a burrow I saw one individual drop his tail down behind him and trail it into the burrow instead of carrying it over his back" (Storer, MS). Often when running an "Ammo" will be seen to jump short distances, quite clearing the ground. "I saw one in a tree yucca where I only came to detect his presence by seeing the shadow of his waggling tail" (Storer, MS). The animals seem to be able to climb the prickly cactuses and yuccas without sustaining any serious injury.
The voice of the Antelope Squirrel is unique among the members of its tribe. It is not a "bark" at all; nor is it a "squeak." It may be described as a prolonged mellow rolling trill, weakening or falling in inflection toward the end. The tone is maintained on about the same moderately high pitch throughout, though an impression of lowering
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