4 BULLETIN 1249, U. S. DEPARTMENT OF AGRICULTURE. 



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 taken falls 

 from 37.96 per cent in winter to 2.79 per cent in summer. This 

 variation is easily understood by considering the habits of the even- 

 ing 'grosbeak. During the winter the birds spread over the Northern 

 States into localities where maples, ashes, and box elders are very 

 common and conifers relatively scarce; during the breeding season 

 they frequent coniferous forests, where seeds of these forms are 

 easily obtained. Weed seed and rubbish complete the vegetable 

 food. 



Beetles and caterpillars are the chief animal food, although small 

 wasps and ants (Hymenoptera), 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 Diche- 

 lonycha, 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 may be counted in the bird's favor. 



Conclusions. — The evening grosbeak is of little economic im- 

 portance. Its food consists largely of the seeds and fruits of various 

 trees and shrubs, none of which are of any material value to man. 

 It might turn its attention to cultivated fruits if they were grown 

 in its summer home, but neither this possibility nor the slight harm 

 done by bud-eating justify an unfavorable attitude toward the 

 species. 



Food items of the evening grosbeak, identified to the genus or species, as de- 

 termined by the examination of 127 stomachs. 



[The figures indicate the number of stomachs in which the items were found.] 



Vegetable Food. 



Pinaceae. 





Rhamnaceae. 





Pinus ponderosa (western yel- 





Ceanothus sp. (Jersey-tea) __ 



1 



low pine) 



11 



Malvaceae. 





Juniperus monosperma 





Hibiscus sp. (mallow) 



2 



(cherrystone juniper) 



2 



Cornaceae. 





Juniperus sp. (juniper) 



12 



Cornus occidentalis (dog- 





Rosaceae. 





wood) 



1 



Rubus sp. (blackberry) 



3 



Cornus sp. (dogwood) 



67 



Malaceae. 





Oleaceae. 





Mains mains (apple) 



1 



Fraxinus sp. (ash) 



4 



Sorbus sp. (mountain-ash) 



14 



Solanaceae. 





Amelanchier sp. (service- 





Solanum sp. (nightshade) 



1 



berry) 



4 



Caprifoliaceae. 





Amygdalaceae. 





Symphoricarpos sp. (snow- 





Prunus sp. (wild cherry) 



26 



berry) 



11 



Anacardiaceae. 





Sambucus (elder) 



1 



Rhus trilobate (skunk- 





- 





bush ) 



1 







Aceraceae. 









Acer sp. (maple) 



35 







Acer negundo (boxelder) 



11 







