Page:Natural History of the Ground Squirrels of California.djvu/57

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THE GROUND SQUIRRELS OF CALIFORNIA.
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mainland ones. Fortunately for the present writers, our appeal to Mr. Frank S. Daggett, Director of the Museum of History, Science and Art, in Los Angeles, was promptly met by action, and Mr. L. E. Wyman of Mr. Daggett's staff was detailed to go to Catalina and obtain a sufficient number of specimens for deciding the doubtful questions. Mr. Wyman was eminently successful, and the resulting series of skins and skulls, together with the accompanying information, was freely placed at our disposal for use in connection with the present paper.

Mr. Wyman found the squirrels fairly swarming May 9 to 16, 1918, at the upper end of a narrow tract of bottom land about a mile back of Avalon. This tract, dotted with elderberry trees, had been seeded to barley, and the grain stood knee-deep except in the spots where it had been persistently eaten down by the squirrels. The hillside adjoining on the northwest was steep and fairly well covered with cactus and chaparral, and in places it was honeycombed with burrows. The bottom of the hill was beset with extensive diggings every fifty feet or so.

Besides the barley, the squirrels were feeding on a variety of wild vegetation. Each of the numerous stomachs examined contained a well-chewed green mass. Cheek-pouches were found to contain barley blades and certain seeds, and in one case four bulbs of "sour-grass" or "grass-nuts" (Brodiæa capitata), the largest of which was half an inch in greatest diameter. These bulbs seem to be specially sought after, as several small areas were found, usually on south-fronting grassy hill-sides, where the ground was all dug up by the animals, and hulls of Brodiæa bulbs were lying about.

One ground squirrel was seen at work in a wild tobacco tree about seven feet from the ground. He had gnawed at the stem near the top until only a shred kept it from dropping. Gnawed shells of chilicothe seeds were also found.

Mr. Wyman believes that the notes and actions of the Catalina Island Ground Squirrel do not differ to any appreciable extent from those of the mainland Beechey. The island animals were perhaps slightly less noisy, though when once started to barking they seemed hardly able to stop. They were found to be shy on open ground, hustling to cover when the invader of their domain was yet 200 yards off. By sitting quietly under a tree, however, Mr. Wyman had one squirrel approach him to within ten yards and feed on barley shoots. On the brushy hillsides, the collector was able to stalk his quarry with ease.

All the females taken were notably fat, and none contained embryos. Also no young of the year were seen; so that it would seem that the breeding season of the island squirrel is much later than that of the mainland animal—later, at least, than May 16. Every specimen taken by Mr. Wyman was "loaded with fleas;" these, however, quickly disappeared and in no case caused any annoyance to the collector.

Since ground squirrels were seen by the senior author commonly in August, 1903, in the vicinity of the Isthmus, near the northwest end of Catalina, it may be inferred that the animals are widely distributed over this island. No species of ground squirrel whatever exists native on any of the other California islands.

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