1308 U.S. NATIONAL MUSEUM BULLETIN 237 part 3 



In March and April 17 out of 55 birds had some insect matter in 

 their stomachs. A wide variety of insects has been recorded: 

 "Hymenoptera," ants, caterpillars, beetles, and weevils. Joseph 

 Grinnell and Tracy I. Storer (1924) state that an adult male mountain 

 white-crowned sparrow taken at Tenaya Lake on July 3, 1915, had 

 nothing but beetles in its stomach. G. F. Knowlton (pers. comm.) 

 collected a female Gambel's sparrow whose stomach was "well filled 

 with five mud-dauber wasps, two ants, six additional Hymenoptera 

 and insect fragments." 



Data on stomach contents of migratory white-crowned sparrows 

 indicate that a shift to insects in the diet may start on the wintering 

 grounds. Of 80 specimens taken in January, February, and March, 

 only 12, or 15 percent, had any insect matter in the stomach, and in 

 only one bird did the insect matter comprise more than 10 percent 

 of the contents. In April 7 out of 21, or 33 percent of birds taken on 

 the wintering grounds had insect matter in the stomach, and in all 

 seven it made up more than 10 percent of the stomach contents. 

 Of 12 Gambel's sparrows taken in migration in April on Saturnia 

 Island, B.C., 11 had stomachs containing between 15 percent and 

 100 percent insect material, with the average percentage of insect 

 matter totalling 73.6 percent. The 12lh specimen of this group had 

 only green vegetable matter in its stomach. Thus the shift to 

 insects as a major component of the diet may occur a month or more 

 before nesting begins. 



Clarence Cottam (pers. comm.) makes the general statement for 

 all species of buds whose stomachs have been analyzed by the Bio- 

 logical Survey, that races of the same species show little difference in 

 their choice of food unless they occupy distinctly different habitats. 

 The data available on food habits of white-crowned sparrows seem 

 to substantiate this statement, although no detailed study of the 

 food of races occupying the same area in winter has been made. 

 As individuals of two or more races commonly forage together, 

 it seems unlikely that any racial differences in food preference exist. 



Voice. — The call notes of the Pacific Coast races are identical, and 

 are used under identical circumstances. The location note, "eep," is 

 used by members of winter flocks and by mated pairs as they forage, 

 move through shrubbery, or fly from one place to another. The same 

 note, uttered more stridently, is given by the female when buidling 

 her nest and when she leaves or returns to her nest during incubation. 

 A modification of this note, which sounds like "ssseep," has already 

 been described as the note uttered by the male prior to and during 

 nest-building. A scolding note, which to my ears sounds like "ip" 

 but which William L. Dawson (1923) writes as "zink" or "dzink," 

 is used to protest intrusion by a person or animal. It is also uttered 



