22 BULLETIN" 107, U. S. DEPARTMENT OF AGRICULTURE. 



tion had taken no less than 100 larvae and 4 adults and another had 

 eaten 44 larvae and 27 adults. Other food items vary but little in 

 their relative proportions from those of May. Caterpillars formed a 

 little less than a third of the contents and ground beetles about a 

 fourth. Hymenoptera, many of which were parasitic ichneumons, 

 composed 6.5 per cent, spiders 4.7, and weevils of the genus Spheno- 

 phorus about 4 per cent. The vegetable element was of no impor- 

 tance. 



By July the abundance of other insect food caused the meadowlark 

 to greatly reduce the proportion of weevils taken. The insect was 

 eaten by only one of five birds examined. This bird, a fully fledged 

 young, had consumed 16 adults of the year's brood, which formed 22 

 per cent of its food, giving an average of 4.4 per cent for the mate- 

 rial collected in this month. Ground beetles and grasshoppers were 

 the most important of the other food items. 



Summary. As a weevil destroyer the western meadowlark renders 

 its most valuable service during the early days of spring, when many 

 breeding adults fall prey to its diligent search. Its fondness for 

 ground beetles and caterpillars, especially cutworms, has a tendency 

 to reduce the percentage of weevils eaten during the following 

 months. The good it does in the destruction of caterpillars more 

 than offsets the harm arising from the eating of ground beetles. As 

 the latter are very abundant throughout alfalfa fields, and as many 

 are of species of doubtful economic value, the bird should not be too 

 severely judged on this score. Examinations show that the meadow- 

 lark, at least from April to July, is not a menace to grain in Utah. 

 On the other hand, its being a resident the year round makes it a 

 valuable asset as a destroyer of hibernating inserts, especially the 

 alfalfa weevil. 



BULLOCK'S ORIOLE. 



(Icterus bullocki.) 



Bullock's oriole secures much of its food from trees, caterpillars 

 being the largest single item. Although the alfalfa weevil in all its 

 stages is found most frequently on or near the ground, it was present 

 in each of seven stomachs collected. Two birds taken in June had 

 fed on it to the extent of 8 J per cent of their food, while in the fol- 

 lowing month it formed nearly twice that amount. One bird col- 

 lected in July had eaten no less than 21 adults, equaling 30 per cent 

 of its food. No larvaa were taken by these birds even though this 

 form of the insect was in great abundance, so that the adults may 

 have been captured either on the wing or upon the branches of trees 

 which had intercepted their flight. 



Of other animal food caterpillars are most important, and they 

 occurred in four of the seven stomachs. One bird had fed almost 



