CALIFORNIA SHRIKE. 35 
A shrike of the eastern subspecies was kept in confinement for some 
weeks by the Biological Survey and notes made in regard to its food 
habits. A thorny bush was placed in the cage, and whenever the 
bird was given food in excess of its immediate wants it impaled the 
surplus upon a thorn, taking great pains to press it securely down. 
On one occasion a dead mouse was placed in the cage; it was at once 
seized and forced into the fork of the bush and was then torn piece- 
meal and eaten. Note was taken of the time when the last bit was 
swallowed, and a close watch kept for further results. In an hour 
and a half the bones and hair of the mouse were disgorged in the form 
of a neat pellet. Everything digestible had been stripped from the 
bones. A May-beetle (Lachnosterna) was eaten and the pellet con- 
taining the remains appeared in an hour and twenty minutes. At 
another time a ground beetle (Calosoma) and a stink bug (Nezara) 
were eaten and their remains appeared in forty minutes. As both 
of the insects are nauseous, at least to human smell and taste, it 
is possible that they may have been unacceptable to the stomach of 
the bird, and so were rejected before digestion was complete. On 
another occasion a second Calosoma and a moth were given, and their 
remains were regurgitated in an hour and fifteen minutes. These 
experiments show how rapid is the process of avian digestion. 
In the investigation of the food of the California shrike 124 stom- 
achs were examined. They were collected in every month, but the 
greater number were taken in the warmer months. 
Vegetable food—Animal food of all kinds amounts to 97.5 percent, 
or so nearly the whole that it is fair to suppose that the greater 
part of the 2.5 percent of vegetable matter present was swallowed 
unintentionally—that is, when sticking to something else. All of it 
was contained in 9 stomachs. Fruit appeared in 2 stomachs, seeds in 
2, and rubbish in 6. Of these probably only the fruit was taken as 
food. One stomach was filled with elderberries to the amount of 84 
percent of the contents, the other with the seeds of blackberries or 
raspberries to the extent of 13 percent. It thus appears that the 
shrike sometimes eats fruit. 
Animal food—The animal portion of the shrike’s food may be 
divided into three parts: Insects, $3 percent ; spiders and a few snails, 
etc., 2 percent; vertebrates, 12 percent. 
Insect food.—In comparing the food of eastern subspecies of 
shrike and the one under discussion, we find that more insects are 
eaten by the western one. The figures for the eastern bird are: 
Insects, 68 percent; spiders, 4 percent; vertebrates, 28 percent. The 
difference is undoubtedly due to climate, the western bird being 
able to find insects all the year round, while the eastern one discovers 
very few during the winter. Insects probably are always preferred 
when obtainable. 
