BIRDS IN RELATION TO THE ALFALFA WEEVIL. 15 



other important components of the food, and in the stomach of one 

 bird were fragments of eggshell. 



In view of the numerous objectionable habits of the closely related 

 California jay it does not appear wise to recommend protection for 

 this bird as a weevil destroyer. At the same time it is not numerous 

 enough in agricultural districts of Utah to make any injurious 

 habits which it may possess noticeable. 



BOBOLINK. 



(Doliclionyx oryzivorus.) 



The bobolink, songster of hayfields and low meadows, is fairly 

 common in Utah. It was found in moderate abundance in the 

 vicinity of West and South Jordan, and Farmington, and along the 

 Weber River and Chalk Creek in Summit County. 



As a destroyer of the weevil it nas an interesting record. In the 

 stomach of each of the nine birds examined the insect was present 

 in considerable numbers. A single bird collected in May had fed on 

 10 adult weevils, which formed 14 per cent of the food. 



Seven bobolinks collected in June had taken the weevil at an 

 average of about 8 adults and 42 larvae per bird, to the extent of 68 

 per cent of the stomach contents. In the stomach of one, 6 adults 

 and 90 larvae formed the entire food. Another had eaten no less than 

 28 adults and 77 larvae, amounting to 86 per cent of the stomach 

 contents, while a third had eaten 3 adults and 61 larvae. The only 

 other food items in the last stomach were small fragments of a bug 

 and a click beetle, estimated at 1 per cent. These birds also had 

 fed to the extent of over 16 per cent of their food on caterpillars, 

 which occurred in all but one of the stomachs. Bugs (Hemiptera) 

 formed about half that amount. 



A single bobolink collected in August had eaten 7 adults, which 

 totaled 15 per cent of its food, while several caterpillars and lepidop- 

 terous pupae formed an additional 71 per cent. 



The bobolink does exceptionally good work as a weevil destroyer, 

 for whenever it lives near infested alfalfa fields the insect forms its 

 most important animal food. There appears to be no reason why it 

 should not be fully protected. Its status in Utah is essentially the 

 same as in the New England and other Northern States, where its 

 economic merits have never been questioned. 



COWBIRD. 



(Molothrus ater ater.) 



Previous investigations 1 of the economic status of the cowbird 

 have shown that, judged from its food habits alone, the farmer has 



1 Beal, P. E. L., Food of the Bobolink, Blackbirds, and Grackles. Bull. 13, Biol. 

 Survey, U. S. Dept. of Agr., 1000. 



