THE GROUND SQUIRRELS OF CALIFORNIA. 



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small and scattered that it did not attract attention. A typical example 

 is as follows. 



Residents of Owens Valley at Lone Pine stated in June, 1917, that 

 the ground squirrels there had only recently invaded the valley and that 

 none were known in that vicinity five years before. But from this same 

 locality specimens now preserved in the Field Museum of Natural His- 

 tory in Chicago were obtained in 1902, fifteen years previously. 

 Although the squirrels are said to be steadily increasing along the west 

 side of Owens Valley, little or no effort appears to have been attempted 

 at controlling the pest. 



At the Carl Walters Ranch, two miles north of Independence, on 

 June 26, 1917, Fisher Ground Squirrels were found to be fairly abun- 

 dant on both this and most of the other ranches in the vicinity. They 

 had been considered a nuisance here for a number of years (A. C. 

 Shelton, MS). 



The irrigation and cultivation of extensive areas have resulted in a 

 greatly increased available food supply which has proven acceptable to 

 the ground squirrel and has resulted in greatly increasing its popula- 

 tion. It is the authors' belief that the squirrels have been present in 

 Owens Valley from time immemorial and that as long as they were 

 few in numbers and stuck to the rocky, uncultivated ground they 

 remained largely unnoticed, but that when they invaded irrigated 

 fields and became numerous they attracted attention and were then 

 thought to have but just moved into the valley. 



It is believed that, on the whole, there are only about half as many 

 Fisher Ground Squirrels to the square mile throughout its range as 

 there are California Ground Squirrels to the same unit of area in the 

 range of that form. Fisher Squirrels nevertheless prove very destruc- 

 tive locally to cultivated crops. Many small isolated orchards and 

 " dry-farmed' ' grain fields are scattered throughout the western and 

 northern parts of the range of fisheri and these frontier ranches are 

 the ones which suffer. While the money value of the crop destroyed 

 may be small, yet such crops are often the settler's principal means of 

 obtaining a livelihood and, although this may be humble indeed, its loss 

 is felt critically. It is the authors' belief that the Fisher Ground 

 Squirrel ranks third, or next after the Oregon Ground Squirrel, in point 

 of economic importance in California. 



CATALINA ISLAND GROUND SQUIRREL. 

 Citellus beecheyi nesioticus Elliot. 



Other names. — Island Spermophile ; Citellus nesioticus; Spermophilus beecheyi, 

 part. 



Field characters. — As for the Beechey Ground Squirrel. Only to be distinguished 

 from it on comparison of series of specimens ; coloration averaging darker, general size 

 greater, and tail relatively shorter. Length of bod^ alone, ; n males, about 111 

 inches; w'th tail (without hairs) about 7£ inches more. 



Description. — Adults in April: Similar to the Beechey Ground Squirrel (San 

 Francisco Bay region) as already described, but general coloration darker; top of 

 head from nose to nape, and broad area down middle of fore back between light 



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