138 



NORTH AMERICAN FAUNA 



[No. 55 



from which they range out widely for food and exploration through 

 the Lilliputian forests of sagebrush. They run swiftly from cover 

 to cover, with tails erect, darting over open ground from one patch 

 of sagebrush to the next, then through the branches and tops of the 

 bushes, or, pausing a moment on one of the highest twigs to inspect 

 the country for danger, with a sharp little chipper are off again in 

 another direction. 



When at a long distance from a burrow or other safe retreat these 

 chipmunks run so swiftly and hide so skillfully in the bushes that 

 specimens are not easily obtained. Even on a good hunting horse 

 the writer has been led many an exciting chase without securing a 

 specimen, while on foot it is useless to pursue one. A little patience 

 and skill, however, will yield more specimens than hard hunting. A 

 few squeaks of the lips will bring one to the top of a sage bush 

 where with alert ears and lashing tail he will answer back in excited 



chippers and fall an easy- 

 prey to his nervous curi- 

 osity. More specimens are 

 secured in mousetraps set 

 among the sage bushes 

 than in any other way, as 

 the chipmunks are eager 

 for rolled oats or almost 

 any of the baits used for 

 rodents. 



B T e e ding haibits. 

 Little is known of the 

 breeding of these chip- 

 munks other than that 

 the female has 4 pairs of 



FIGURE 23. Range of the sagebrush chipmunk, rnammap 1 incrninal 9 



Eutamias minimus pictus, in Oregon. mgumai, A 



abdominal, and 1 pecto- 

 ral and that 4 and 5 are the usual numbers of embryos found in 

 those collected for specimens in May. There seems to be no evidence 

 of more than one litter being raised in a year, but there might be a 

 second litter under favorable circumstances, such as mild climate, 

 abundance of food, and freedom from persecution of enemies. The 

 young are generally nearly full grown by harvest time in the fall, 

 and apparently each makes its stores independently. 



Food habits. The sagebrush furnishes food as well as shelter for 

 these tiny squirrels, its abundance of minute seeds being gathered 

 /and carried away in the cheek pouches all through the late sum- 

 mer, fall, and early winter. In return for this food supply, the sage- 

 brush is to some extent protected from insects by the chipmunks, 

 which in summer often subsist largely upon the little green cater- 

 pillars that devour its leaves. The stomachs of the chipmunks often 

 show traces of grasshoppers and numerous other insects, but the bulk 

 of their food generally consists of seeds of a great variety of flower- 

 ing plants and grasses, berries, green vegetation, roots, bulbs, and 

 fungi. They are fond of grain and often gather around the edges of 

 fields to feast on this unusual food supply and store as much as 

 possible for winter use. They do not become very fat in the fall 

 and probably do not hibernate for any long period, if at all. 



