Page:Natural History of the Ground Squirrels of California.djvu/40

626 or bulbs which they have discovered, their cheeks are seen to be bulging with the contents of these pouches. They are able to operate their teeth and lips even when these pouches are copiously distended. The cheek pouches of the California Ground Squirrel are especially well developed and this, we think, is correlated with the pronounced seed gathering and storing propensities of this species. The following records of cheek-pouch contents, as secured from specimens collected, contribute further to our knowledge of the kinds of food of this animal and also of the quantity in which these may be gathered.

A female taken in a stubble field near Walnut Creek, Contra Costa County, July 26, 1918, held in her cheek pouches 26 seeds of bur clover. A male taken August 15, 1918, at the same place had 78 seeds of bur clover and one seed of needle grass. Two other males had one and three bur-clover seeds, respectively. Another female taken at the same time and place contained 212 seeds of bur clover and 12 seeds of some kind of wild grass. Another male held 97 grains of barley and three bur-clover seeds. A ground squirrel taken at Cisco, Placer County, on October 9, 1913, was carrying 92 seeds of the green manzanita (Arctostaphylos patula), while a squirrel secured near Pleasant Valley, Mariposa County, on May 28, 1915, had dug up and was carrying in its pouches 12 bulbs of a species of wild hyacinth (Brodicea hyacinthina). At El Portal, Mariposa County, a squirrel was secured with three large acorns of the golden oak in its cheek pouches.

We will now consider those feeding habits which make the California Ground Squirrel come into conflict more directly with man's interests. "Of cultivated nuts, almonds and walnuts are preferred; of other crops, apples, prunes, peaches, apricots, figs, olives, the seeds of cantaloupes, watermelons and citron melons, and all the grains are eaten whenever they are to be had, and green alfalfa and clover are sometimes taken" (Merriam, 1910, p. 5). Frank Stephens (1906, p. 66) has summed up the food taken by this animal as follows: "The food is principally of a vegetable nature, preferably grain and other seeds, fruit, potatoes, green plants, etc. Eggs of poultry and wild birds are relished." We have heard considerable testimony from ranchers to the effect that individual ground squirrels in different localities have learned to raid henneries, so that the above statement is not exceptional.

A great deal of damage is done by California Ground Squirrels each year in orchards and vineyards. The following instances, given by Merriam (1910, p. 6) are typical of such depredations. "Ground squirrels are particularly fond of green almonds and of the pits of green peaches and apricots, eating these from the time the kernels begin to form until the fruit is ripe, thus doing serious damage. They are very destructive to apples also, and in places in the foothills of the Colfax-Auburn region are said to take fully half the crop In the fall of 1907 E. A. Goldman reported that they were doing serious damage to young vineyards about Orosi, in Tulare County, by biting off the leaves and tender shoots of the vines In the orange groves between Porterville and Springville, in Tulare County, it is reported that they occasionally gnaw the bark of the orange trees and sometimes cut the fruit and carry it off. Besides destroying nuts and fresh fruits they attack drying prunes and carry off large quantities."