28 FOOD OF BOBOLITfK, BLACKBIRDS, AND GRACKLES. 



aggregate for the year is 6. 6 percent. Wheat was found in onlj-^ 20 

 stomachs, and amounts to 1.4 percent of the year's food. Like corn, 

 its distribution is irregular and does not appear to have an}^ relation to 

 the seasons. It is probable that it is a purel}^ accidental food, eaten 

 only when nothing better is to be had. The greatest quantity (-i.S per- 

 cent) was taken in September. A single kernel of buckwheat was 

 found in 1 stomach. 



Grain as a whole amounts to 16.5 percent, or practicall}" one-sixth 

 of the food of the j^ear; but a consideration of its distribution as given 

 above leads to the conclusion that a large portion of this, probably 

 one-half, is waste. In comparing the record of the cowbird with that of 

 the red-winged blackbird, the cowbird's shows the greater consumption 

 of grain; that is, 16.5, as against 13.9 for the redwing. In view of this 

 fact it would seem somewhat strange, were not a large proportion of 

 the grain consumed waste, that no complaints should have been made 

 against the cowbird on the scoi"c of grain eating. It is possible, of 

 course, that observers have not alwa^'s distinguished the two species 

 in the field, as male cowbirds do not differ greatly in color or size from 

 female redwings — and their great abundance in the West lends some 

 color to this supposition. But it seems far more pr()l)able that they 

 gather a very important part of the grain found in their stomachs in 

 their gleaning in roads, about barnyards, and wherever cattle arc 

 found, and so do far less actual damage to growing crops than the 

 redwings. 



Fruit forms an iiisigniticant part of the food. Some traces of what 

 may have been fruit pulp were foimd, and a few seeds of raspberries 

 v/ere in each of 4 stomachs, and some hhielwrry seeds in one; ]>ut as 

 some of the I'aspberrv seeds were in stomachs collected in April they 

 were evidently eaten as dry seeds, and this may have ])een true of all. 



The seeds of plants classiticd as weeds in the list of vegetable food 

 constitute ])y far the most important part of the diet. They form the 

 largest item of food in every month except July and August, and are 

 of importance in ev^er}^ month. Beginning with 61.4^ percent in 

 elanuary and 95.5 percent in February, they slowly decrease to 16.6 

 percent in August, but rise suddenly to 58.1 percent in September, 

 attain their maxinmm of 97 percent in Octol)er, and end with {>6.8 

 percent in December. They constitute practically the whole food of 

 the winter months. The aggregate for the year is 60 percent of all 

 the food, or more than three-fourths of the vegetable food, and more 

 than three and a half times the total amount of grain. Barngrass and 

 ragweed are especially well known as troublesome weeds throughout 

 the country wherever field crops arc culti\'ated, and these two consti- 

 tute the great bulk of this food. Barngrass seed was found in 265 

 stomachs and ragweed in 176. Panicums, while ostonsiblv foliage 

 plants, are often troublesome weeds. Their seeds were found in 133 



' Based on 3 stomachs. A larger uumljer would probably greatly increase the 

 jtercentage. 



