WESTERN EVENING GROSBEAK 247 



13 stomachs. Juniper berries had been eaten by 14 birds, and seeds of other 

 conifers by 13. 



The nature of the contents of certain stomachs of this species gives a vivid idea 

 of the shearing or crushing power of the beak. The seeds of cherries were broken 

 easily and a whole one was rarely found. The flattened seeds of the snowberry 

 were split longitudinally in nearly every case. 



The food for the summer season, as determined by an examination of 39 stom- 

 achs, is 20.82 per cent animal and 79.18 per cent vegetable matter. 



The vegetable food was of much the same character as that taken during the 

 winter season. Seeds of wild fruits are 37.87 per cent of the food for the summer 

 compared with 39.63 per cent during the winter. The greatest difference is in 

 the relative quantities of winged seeds and those of conifers. The percentage of 

 the latter rises from 14.5 per cent during the winter to 28.45 per cent in summer, 

 while in the case of winged seeds the amount falls from 37.96 per cent in winter to 

 2.79 per cent in summer. * * * Weed seed and rubbish complete the vegetable 

 food. 



Beetles and caterpillars are the chief animal food, although small wasps and ants 

 (Hy menoptera) , bugs (Hemiptera), and spiders were also eaten. Among the 

 beetles were found a few of the useful predacious ground beetles (Carabidae), which, 

 however, amounted to less than 1 per cent of the food. Similar small quantities 

 of weevils and click-beetles, both harmful forms, had been taken. The bulk of 

 the beetles eaten was of the leaf-eating scarabaeid genus Dichelonycha, which 

 feeds on pine, willow, hickory, and other trees and shrubs. One bird had taken 

 41 of these beetles and another 10. Caterpillars to the extent of 11.49 per cent 

 of the total food had been devoured; and as caterpillars with few exceptions may 

 be classed as harmful, this is to be counted in the bird's favor. 



The only reference I have to possible salt-eating in this race is a 

 letter from Gardner D. Stout, who writes: 



"On July 16, 1965 I was driving in western Colorado near Meeker 

 at about 9,000 feet altitude just about daybreak. The road was cut 

 through a series of five rolling clay ridges, and the banks of each cut 

 rose almost vertically beside the road. Clinging to the bank faces 

 in each cut were roughly 150 Evening Grosbeaks apparently picking 

 at the clay and eating it. Unfortunately I was unable to climb up 

 to see whether or not these clay banks contained any salt, but there 

 was no seepage from them." 



Behavior. — H. Brandt (1951) gives a clear picture of its method of 

 flying: "The flight is direct and rapid with pinions fully extended, 

 and accompanied by constant rapid wing-beats. The white patch 

 on the wings then produce [sic] a continuous variegated flash of 

 signs that distinguishes this bird from others. Sometimes a whole 

 flock of considerable size will take wing as though by a single impulse ; 

 or depart in single file." 



In watching a large flock at Santa Fe, Brandt comments about 

 their docility: "Never did I see a bird make a single hostile move 

 toward another." Charles W. Michael teUs a very different story. 

 He writes from Yosemite (MS.): "One spring morning I happened 

 to witness an interesting show with evening grosbeaks as the actors 



