Till'] STIUl'IOI) (illOllND SQlJIIillKLS OF ('OLOKADO 



11 



destroy only what they eal. Around the prairie-dog holes the 

 grass is always killed for several feet. Not so with this squirrel. 

 You will often find the grass u]) to the mouth of the holes, making 

 them at times difficult to see. 



The burrows of the striped ground s(piirrel, as a rule, des(!end 

 for a short distance almost ])erpendicularly, and then branch off 

 horizontally. These squiri-els do not always live in burrows inade 

 by themselves, but at times occujiy the deserted burrows of other 

 nnimals — prairie-dogs, kangaroo rats, etc. 



In years past, when the vast plains of Colorado were still 

 virgin soil and the hand of man had not hevn raised against it, 

 the balance of nature was so evenly regulated that the predaceous 

 birds and mammals— hawks, owls, coyotes, badgers, skunks, and 

 weasels — kept in check any undue increase in destructive rodents ; 

 but now the hand of man is reaching out farther and farther into 

 these vast plains. He is encroaching on the ground squirrels' 

 domain, and with the march of civilization, in his thoughtlessness, 

 he is destroying these predaceous birds and mammals that serve 

 to keep in check the rodents that feed upon his crops. With the 

 destruction of the natural enemies of these rodents, and furnish- 

 ing them with a new source of food supply, it is no wonder that 

 they are increasing. 



Different Foods Reported Eatex by Citellus t. jMillidus 



Sunflower seed Alfalfa roots and leaves 



Grass seed Corn 



Dandelion seed Cane 



Pumpkin seed Oats 



Sugar beet seed Wheat 



Watermelon seed Kaffir 'c(n'n 



Muskmelon seed Rje 



Young chickens Mi lo maize 



Squash seed Peas 



Speltz Barley 



Beans Peanuts 



Grasshoppers Beetles 



Crickets Field mice 



Contents of Stomachs 



The stomachs of the striped ground squirrel (Vitellus tride- 

 cemlineatus pallidus) mentioned below have been examined to 

 determine the food contents. " These stomachs were taken from 

 squirrels trapped in alfalfa fields, native pastures, cultivated 

 fields, and along ditch and railroad embankments. Unlike the 

 birds, which swallow the food whole, the ground squirrel, like 

 all rodents, thoroughly chews its food before swallowing, so that 

 the soft parts of the insects are in such shape as to be almost im- 

 l)0ssible of identification ; but, as a rule, enough of the legs and 

 antennae remains so that one can be sure of the order, and in 



