98 DENIZENS OF THE DESERT 



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 com- 

 pact and offer favorable conditions for con- 

 structing 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 uni- 

 formly 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 tri- 

 angular in outline and have very little earth 

 thrown up at the entrance; it is thus easy to 



