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CIRCULAR 



U. S. DEPARTMENT OF AGRICULTURE 



One of the most important natural checks on pocket gophers appar- 

 ently is water. Beaver dams raise the water table in some places and 

 provide moist meadows. As a result, pocket gophers are driven or 

 drowned out by the rising ground water. Those that survive leestablish 

 themselves on the drier margins of the meadows. Much the same results 

 have been observed where water tables were raised by artificially dam- 

 ming gullies running through meadows. In years of high precipitation 

 or of heavy stream flows, flood waters spreading over the meadows flood 

 burrow systems and drown the gophers. 



Animals, insects, and diseases 

 help control pocket gophers. 

 Predators include hawks, owls 

 (fig. 13), coyotes, bobcats, badgers,, 

 weasels, and snakes. However, 

 these predators probably are less 

 numerous than they were before 

 livestock came into the country 

 and may not be as effective a 

 check as they were under undis- 

 turbed conditions. Gophers on 

 the study area were not examined 

 for internal parasites, but fleas, 

 ticks, and mites were found to be 

 common. Occasionally a warble 

 was found under the skin in late 

 summer and fall. One individual 

 carried on its back a fully de- 

 veloped warble and four fresh 

 warble scars. Newborn young in 

 some nests had decomposed navel 

 areas, a condition apparently ag- 

 Figure 13.— An owl's pellet containing a gravated by rainy springs and 

 pocket gopher skull. damp nest material. 



Artificial Control on Mountain Meadows 



The safest and most effective method of controlling pocket gophers on 

 mountain meadows 8 is the use of strychnine-treated sweetpotatoes or 

 carrots. 



CAUTION: Strychnine is poisonous. Always keep poison baits out 

 of the reach of children and livestock. 



Poisoning can be done most effectively on mountain meadows in the 

 fall, when rains have softened the soil and the gophers are most active. 

 Their mounds are located more easily at that time because livestock will 

 have grazed the rank vegetative growth that hides the mounds in the 

 summer. Spring work is not satisfactory because surface indications of 

 gopher work are so limited that it is difficult to find the runways. 



Baits are prepared by cutting large sweetpotatoes or carrots into 

 pieces 1 1/ 2 inches long and i/ 2 inch square. Sweetpotatoes are more effec- 

 tive as bait because they remain attractive to the gophers longer than 



* For a detailed description of methods to be used when controlling pocket gophers 

 on other lands see reference (2) . 



