60 FOOD HABITS OF THE GROSBEAKS. 



BLACK-HEADED GROSBEAK. 



(Zamelodia melanocephala. Plate III.) 



APPEARANCE, DISTRIBUTION, AND HABITS. 



In form and size the black-headed grosbeak is almost a counter- 

 part of the last species, but it is very different in color. In the male 

 blackhead, golden brown and lemon yellow take the place of the 

 rose and white of the rosebreast; while the color of the underparts 

 of the female is not soiled white, as in the eastern bird, but bright 

 buffy. Both sexes of the western grosbeak have a horn-colored beak ; 

 that of the rosebreast is white. 



Occupying a range from the west coast eastward which is comple- 

 mentary to, although slightly overlapping that of its eastern relative, 

 the blackhead occurs from lowermost Mexico to southern British 

 Columbia, northern Montana, western North Dakota, and north- 

 eastern Nebraska. It breeds at both extremes, and withdraws in 

 winter to the southern third of its range, lingering as far north, how- 

 ever, as central Mexico. 



The male is a brilliant songster, the peer of any of his kin. He is 

 also an excellent mate and parent, and assumes an equal share of the 

 labors of the nesting season. The nests of this species are loosely 

 built and generally are placed in low growth, often along streams. 

 The eggs are 3 or 4 in number and are similar to those of the rose : 

 breast. The young are hatched in May and June. Since the bird 

 often makes its home in higher altitudes it is sometimes called the 

 mountain grosbeak. 



ECONOMIC RELATIONS. 



So great is the economic importance of the black-headed grosbeak 

 that partial accounts of its food habits appear in two previous pub- 

 lications of the Biological Survey.^ Only TO stomachs were then 

 available for examination, while more than three times that num- 

 ber b are now at hand, collected in five States and Territories. As 

 the greater number are from California, the present report relates 

 essentially to that State. The stomachs were collected from April 

 to August, inclusive. The data show that about two-thirds of the 

 bird's food consists of insects and other animal matter and one- 

 third of vegetable substances. To be more exact, 65.85 percent is 

 animal, 34.15 vegetable. The maximum amount (79.95) of animal 

 matter is consumed in June. From the standpoint of the agricul- 

 turist great interest attaches to the vegetable food of this bird, as 

 it is reputed to be destructive to cultivated fruit. 



a Farmers' Bull. 54, 1904, pp. 35-36 ; Yearbook Dept. Agr., 1904, pp. 246 and 

 248. 



6 About half of the total number of stomachs of this species were examined 

 by Prof. F. E. L. Beal. 



