while at 8,500 feet on Mount Pinos, Ventura County, a similar sized young one was taken July 11, 1904, At the former locality three juveniles and an adult female were drowned out of one community burrow in an almond orchard. This is probably about the minimum number in a litter, as the average number of young in a litter appears to be only slightly less than in the California Ground Squirrel. "The average number . . . of young at a birth . . . along the borders of the Mohave Desert appears to be . . . 6 or 7" (C. H. Merriam, 1910, p. 4). At Schain's Ranch, San Jacinto Mountains, on June 18, 1908, a family of eight young ground squirrels was observed aboveground at one time at the mouth of a burrow (W. P. Taylor, MS).
Regarding food preferences of this sub-species a special feature has been noted with extraordinary frequency, as follows. Many Fisher Ground Squirrels are taken in meat-baited steel traps set for predatory carnivores under circumstances which make it seem certain that they were caught while trying to steal the bait. They have also been known to eat woodrats and even other individuals of their own kind which they have found dead in traps.
At Kelso Pass, Kern County, on July 8, 1911, two Fisher Ground Squirrels came to drink at a seepage from a spring. One drank six times, the fifth time for over two minutes, by count of seconds (J. Grinnell, MS).
The following records of cheek-pouch contents establish some of the sorts of food taken by this animal. At Taylor Meadow, Tulare County, a squirrel was taken on July 25, 1911, with 88 seeds of a lupine (Lupinus grayi) in its cheek-pouches. Another squirrel taken seven miles above Kernville, Kern County, on June 26, 1911, was carrying a seed of the Digger Pine (Pinus sabiniana); while a third squirrel taken at Lone Pine, Inyo County, had gathered and placed in its cheek pouches 118 seeds of Encelia frutescens and 5 seeds of Hymenoclea salsola.
Squirrels of this subspecies were found doing a large amount of damage to the almond crop at Cabezon, Riverside County, on May 16, 1908. Here they were living right in the almond orchard, most of the inhabited burrows being dug close to the roots of the trees. Other short, shallow burrows were noted, but these were thought to be of use only for temporary protection in case the animals were taken by surprise (C. H. Richardson, MS).
In Antelope Valley, near Fairmont, Los Angeles County, on June 22, 1904, the authors found ground squirrels doing enormous damage to almonds, climbing the trees and biting open the green fruit to take out the pit and often leaving the hull in place on the tree. The pit was frequently found to have been removed from a remarkably small hole in the side or end of the shell.
At various points within the range of fisheri we have been told by old residents that digger squirrels have only recently invaded the locality and that a few years ago there were none where many squirrels are now present. In many such cases the sudden increase in the number of ground squirrels is evidently due not to invasion from without, but to the breeding up, under favorable conditions, of the local stock of squirrels which have been present all the time, but which was formerly so
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