Denizens Of The Desert:
California Road Runner
Neotomas, Or Pack Rats, Of The Desert
Billy Bob-tail, The Hermit Wood Rat
Spiny Pocket Mice
Catherpes, The Canon Wren
Betsy Bounce, The Rock Wren
Round-tailed Ground Squirrel And Near Relatives
Eleodes, The Beetle That Stands On His Head
Read More Articles About: Denizens Of The Desert
( Originally Published Early 1900's )
THE antelope chipmunks, or ammos, as they are sometimes called, are the liveliest, most active and agile of all the small mammals of the desert, and they hold an interest to us out of all proportion to their size. As they dash across the sands at such lively clips as they are wont to go, they remind us of tiny rabbits, immediately attracting our attention with their little white tails, or flags, which they carry curled up over their backs. So many points of resemblance are there both in general appearance and in movements between these little rodents and the chipmunks of the mountains that the desert people call them chipmunks, though they are really very small ground squirrels.
The desert antelope chipmunks are found in great numbers both on the Colorado and the Mohave Deserts, and beyond the borders of California nearly related species are found living in Arizona, Nevada, western Colorado, Utah, and New Mexico. In general they con-fine themselves to the rocky hills and the borders of the desert where the soils are compact and offer favorable conditions for constructing their burrows. There are a few places where they are found well up in the mountains (4000-7000 feet), but in these localities the climate is very dry and the plants are desert-loving species. These spermophiles require a dryer climate than that existing in the coastal valleys, and in only a few instances have they been known to establish themselves on the Pacific side of the mountains.
The ammos do not localize their burrows or live in close colonies like many of the ground squirrels, but scatter their holes out quite uniformly over their range. They make their bur-rows in places affording a protection against enemies that dig, such as coyotes, weasels, and badgers, choosing a site generally near some bush or rock. The holes are distinctive in that the openings are generally more or less triangular in outline and have very little earth thrown up at the entrance; it is thus easy to learn to tell them from the retreats of other small mammals of the region. The burrows are neither deep nor extensive. Last spring a number of desert chipmunks took up their residence near my house, moving from their quarters down on the flat up onto the mountain-side into an abandoned wood rat's hole, so that they could be nearer the place where I kept food out for the birds. Many a dispute they then had with the desert sparrows, the towhees, and the rock wrens at the food table. Being more audacious and pugnacious, the chipmunks always cleared the way for themselves and sent the poor birds away to get their share of the grain when they could.
Among this lot of ammos was one bully, a very large fellow, who always ruled the food yard with an iron hand; and he let it be known that all others who ate there did so at his sufferance. Upon his arrival the other chipmunks generally scurried off a little way and then approached cautiously to test out his good nature before eating in his presence. They seemed to understand that he had marked out his sphere of influence and that he was able to defend it against all encroachers. Very often there was much quarreling going on among them, and this was always accompanied by a great deal of noise, the ammos making sounds much like those made by quarreling mountain chipmunks.
Altogether there are about a dozen of these "chipmunks" that feed near my shanty, and during the day when no one is around to disturb them I generally find most of them nosing around hunting for something to eat. The number of track-marks that they make on the soft dirt in a day is amazing. Hardly a square inch of ground is there which they do not cover. Not a thing that is edible and open to their reach is undiscovered. Like most rodents, they are able to consume a surprising amount of food, and when they have more than they want they carry off the rest in their cheek pouches. When they find a store of food they are indefatigable workers, and will not leave it until the whole of it is placed safely away. Several times they got into the burro's barley bag, and I found that, though the cheek pouches of a single chipmunk hold but slightly more than a heaping teaspoonful of food, yet in a day they could carry away several quarts of grain.
The bill-of-fare varies a good deal with the change of seasons. During the early spring when succulent food is plentiful they eat many green plants. At other times they live on seeds such as those of the tree yuccas, cactuses, scrub junipers, and many kinds of grasses. During a part of the year they add to their dry diet the fruits of the cactuses. Like a great many of the smaller rodents they will eat ;flesh if they can get it.
In their search for food they become very brave even in the presence of people, and if one is quiet they will even enter the house and really become quite tame. They are always on the alert, however, and ready to run when the time comes for them to seek safety in retreat. Like the mice and wood rats they do not mind noise much, but the sight of any motion, how-ever slight, is a signal of danger that sends them off to their holes in a hurry.
The ammos are quite dexterous in their use of the forepaws and they generally use them as hands to hold food up to their mouths.
Since at such times they are much given to sitting up on their haunches they assume quite a human aspect. I was recently much amused at the use a little chipmunk made of his "hands" while scratching for fleas on his rump. Not being able to get at the parts that itched very easily he grasped the skin with his left forefoot and stretched it around forward where with his right forepaw he could reach it. He saw to it that the skin was stretched tight and then proceeded to give it a thorough scratching. The little foot moved bewilderingly fast. Dear little fellow, even he had his troubles.
The antelope chipmunks are easily caught in box traps, but, unless caught very young, they make poor pets, being so shy that they stay closely hidden in the cages provided for them and seldom show themselves when any person is around. I have several times tried to tame them, but I have always soon set the little creatures free, reproaching myself for ever having subjected them to the fear which accompanied their being placed in a box.
Their progress when running is accomplished by a series of short, bouncing leaps, the tail meanwhile being carried well over the back. When an ammo is pursued, he seldom goes straight to his hole. Generally he runs a little way and then stops and looks back to see if you are still coming. If you also hesitate, he will sit up on his haunches in true ground-squirrel fashion and with his head to one side assume a listening attitude. In this position of alertness he may remain for some moments. All the time the nose and the little side whiskers are kept in constant motion, and the tail is vibrated too. If now he is chased into his hole, the little fellow will stay underground for some time before venturing forth. His sense of caution is very great, and he will see to it that you are well out of sight or a good distance away before he again comes out into the open.
The antelope chipmunks do not like cold, cloudy, or rainy weather and they seldom come out of their burrows at such times unless very hungry. But the minute the showers are over they will be out everywhere enjoying' the opportunity, for exercise and foraging. During the winter months those living in the colder deserts and up in the mountains may spend several months hibernating, but those on the Colorado Desert are active all through the year. How-ever, even there the cold mornings of winter generally keep them in their burrows until nine or ten o'clock or until the sun has warmed up the rocks. They retire correspondingly early in the afternoon. Only once have I known a chipmunk to be out after dark. One evening in January at about 7.30 o'clock I heard plainly just outside my door the twittering, trill-like call of an ammo. What could have been the occasion for his being out at such a time must be left to conjecture.
Though these rodents can get along for unusually long periods without water, they enjoy a drink as well as almost any animal when they can get it. On the warm, dry summer days they frequently come down to the little ditch below my dwelling and, catlike, lap up the water. Frequently after they have drank they squat down on the sand and enjoy the shade of the mesquites. Generally they take a belly-down position with their little rear legs flattened out behind them. This, too, is the position they assume when during the heat of the day they are resting under the cool rock ledges along the mountain bases.
As one rides over the desert one often hears the ammos' high-pitched, quavering call. It is so shrill and so prolonged that one can hardly believe that it comes from so tiny an animal. It may last for several seconds and only diminish in intensity and volume during the last phase, sounding then as though the little creature who makes it was losing his last vestige of breath. Since the call carries so far and possesses ventriloquistic qualities, it is exceedingly untrustworthy as a means of locating the animal.