Page:Natural History of the Ground Squirrels of California.djvu/124

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THE MONTHLY BULLETIN.

of alfilaria and keeping a careful watch at the same time upon the intruder. A few days later a squirrel of this species was seen gathering dry seeds of the alfilaria. It is difficult in the field to be sure just what kind of seeds the squirrels are seeking out, since the seeds are too small to be seen at any great distance even with the aid of binoculars, and the stomach contents are so finely chewed that it is impracticable to identify the food constituents.

On one occasion an individual was seen to eat the dried flesh from the hind leg of a dead kangaroo rat. This sort of provender had been secured from a near-by meat-baited steel trap. From this incident we conclude that this species of squirrel is not altogether vegetarian in its food preferences.

Very little information is at hand regarding the food carried in the cheek-pouches of this rodent. A specimen taken at McKittrick, Kern County, on May 19, 1911, had 744 seeds of the alfilaria (Erodium cicutarium) in its cheek-pouches. No food stores of any kind were found in the few burrows excavated.

The Nelson Antelope Squirrel is distributed unevenly. It occurs in abundance at only a few localities. At one of these favored localities, eight miles northeast of Bakersfield, squirrels of this species were found scattered over the low hills in little colonies of six or eight individuals (H. S. Swarth, MS). It is believed that there were certain small areas here that supported at least twenty-five of the squirrels to the acre. However, they were present to this extent on only a small per cent of the total acreage inhabited. At San Emigdio Ranch ten squirrels represent the greatest number found on any one acre. At McKittrick the number per acre was thought to be not over five. Taking the entire range of the species into consideration, there is probably about one squirrel to every two acres.

Our impression is that on the east side of the San Joaquin Valley the range of this squirrel is now being rapidly restricted by farming activities. In 1911, and again in 1918, no Antelope Squirrels whatever could be found in the vicinity of the type locality, Tipton, in Tulare County, where it was common in June, 1893 (Merriam, 1893, p. 129). The first Nelson Squirrel was noted in the 1911 search thirty miles south of Tipton. The gradual settling up of the country, and the cultivation of the kind of ground inhabited by this squirrel, has resulted in the crowding out of the species over much of the eastern part of its original range. It seems only a question of time when continued reclamation will gradually restrict and eventually exterminate this species over the arable portions of the San Joaquin Valley.

The Nelson Antelope Ground Squirrel is at the present time of little or no economic importance. It inhabits barren situations, apart from cultivated land. Our opinion is that this squirrel is not likely ever to become a pest.


LOS BAÑOS ANTELOPE GROUND SQUIRREL.

Ammospermophilus nelsoni amplus Taylor.


Other names.—Nelson Ground Squirrel, part; Antelope Chipmunk, part; Ammospermophilus nelsoni, part.

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