WESTERN POCKET GOPHER 



loose earth, or when it occasionally reaches out for clover or 

 other food. These animals are clever engineers and drive 

 their tunnels long distances. A single animal may construct 

 a widespread labyrinth of subterranean passages, a great many 

 feet in extent, during the course of a summer, where soil con- 

 ditions are favorable. These burrows are driven to new 

 feeding grounds, and the fresh earth thrown out every twenty- 

 four hours proves that the Pocket Gopher is active and ener- 

 getic. 



Most of the digging is probably done with the foreclaws, 

 but the incisors are used to some extent and are broad, capable 

 tools. The burrows may be from a few inches to a foot or 

 more below the surface, and frequent short laterals or "rises" 

 are cut to the surface to get rid of the loosened earth. In 

 contradistinction to the Mole which forces the earth to one 

 side, displacing it by sheer strength, the Gopher cuts a clean 

 burrow and brings all the debris to the surface, or to some 

 unused part of the runway system. Where the soil is damp 

 and loose and the animals can make new burrows without an 

 excessive amount of labor, "gopher-hills" of fresh earth may 

 be seen at intervals of lo to 20 feet wherever one of these 

 creatures is at work, A completed "hill" hides the mouth of 

 the burrow, because the Gopher usually leaves a plug of soil 

 in the last few inches of its length. Probably this is done to 

 keep out snakes and other enemies. It has been stated that 

 these animals have an aversion to light and plug up every 

 opening to shut out light, but the reason just given seems more 

 cogent. Sometimes close inspection reveals the outline of the 

 burrow opening where the earth has issued, but more often the 

 opening will be completely covered by a copious mound. 



Short lateral burrows at which the Gopher is feeding are 

 often without very much soil at the entrance, and the open- 

 ing is closed between meals by only a thin plug which does not 

 come quite flush with the surface. Such a spot may be 

 revisited in an hour or two with a fair chance of seeing the 

 occupant at work. 



Much of the Gopher's food is secured below the surface as 

 roots, bulbs, etc., but some is also taken immediately at the 

 mouth of the burrow. The animal is loathe to leave the hole 

 completely and stretches out only the forepart of its body, 

 with the tail and hind quarters in the burrow, and is prepared 

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