BIRDS AND INSECTS. 305 



those who even believe that successful agriculture would be im- 

 possible if it were not for the assistance of birds. 



Each kind seems to have a certain work to do. The fare of 

 some consists almost wholly of noxious weed seeds, some feed on 

 seeds and insects, and others subsist almost wholly on insects. 



It has been estimated that in an agricultural state like Iowa, 

 that tree sparrows eat approximately 875 tons of weed seeds an- 

 nually. 



The U. S. Department of Agriculture has estimated that the 

 total consumption of weed seed by the combined members of the 

 sparrow family would result in a saving) of i per cent in our 

 crops, annually. 



The Biological survey of the United States has examined the 

 crops and stomachs of upward of 50,000 birds, during the last 

 25 years. This has been done to obtain data upon which to base 

 legislation for their protection. 



To quote the report from the U. S. Department of Agri- 

 culture : 



"A tree swallow's stomach was found to contain 40 entire 

 chinch bugs, and fragments of many others, besides 10 other 

 species of insects. A bank swallow in Texas devoured 68 cotton- 

 boll weevils, one of the worst insect pests that ever invaded the 

 United States; and 35 cliff swallows had taken an average of 18 

 boll weevils each. Two stomachs of pine siskins from Haywards, 

 Cal., contained 1,900 black olive scales and 300 plant lice. A 

 killdeer's stomach taken in November in Texas, contained over 

 300 misquito larvae. A flicker's stomach held 28 white grubs. A 

 nighthawk's stomach collected in Kentucky contained 34 May 

 beetles ; the adult form of white grubs. Another nighthawk from 

 New York had eaten 24 clover-leaf weevils and 375 ants. Still an- 

 other nighthawk had eaten 340 grasshoppers, 52 bugs, 3 beetles, 

 2 wasps and a spider. A bobtailed grackle from Texas had eaten 

 at one meal about 100 cotton .bollworms, besides a few other 

 insects. A ring-necked pheasant's crop from Washington con- 

 tained 8,000 seeds of chickweed, and a dandelion head. More 

 than 72,000 seeds have been found in a single duck stomach 

 taken in Louisiana in February. 

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