BIRDS IN RELATION TO AGRICULTURE 171 



experienced cutworm-hunter, and these bu"ds have been 

 observed in large flocks destroying cutworms in badly in- 

 fected fields, which they carefully work over. When fields 

 are ploughed they follow the plough and consume immense 

 quantities of the destructive white grubs, one of our worst 

 agricultural pests. Where, through their numbers, crows 

 become destructive, it is necessary to take steDs to reduce 

 them. 



The woodpeckers are specially fitted by nature to destroy 

 the wood-boring insects that so speedily kill our forest, 

 shade, and orchard trees. The flicker feeds largely on ants; 

 a single stomach has been found to contain over 5,000 ants. 

 In another instance 28 white grubs were found in the 

 stomach of one of these birds, which feed largely on the 

 ground. The downy woodpecker feeds largely on the borers 

 of trees, and is one of our most useful insectivorous birds. 

 An examination of 723 stomachs showed that 76 per cent 

 of the diet was animal food, consisting chiefly of insects. 

 The yellow-bellied sapsucker is practically the only member 

 of the woodpecker family that is injurious. Its fondness for 

 the inner bark of trees leads it to girdle the trees with holes, 

 the effect of which is either to kill the trees outright or 

 seriously disfigure the timber. 



Chills are constantly associated in the minds of most peo- 

 ple with the sea or our large inland lakes, and their agri- 

 cultural value is therefore largely obscured. Nevertheless 

 there exist very extensive breeding-places of certain species 

 inland, and such a species as Franklin's gull is a true inland 

 species. Sometimes hundreds of ring-billed, herring, and 

 Franklin's gulls may be seen following the plough on the 

 prairie and feeding on the white grubs, wireworms, and 

 other insects and their larvae that are turned up. It has 

 been found that about four-fifths of the food of the Frank- 

 lin's gull consists of grasshoppers. 



From the foregoing review it is obvious that all the chief 

 groups of birds contain representatives, or entirely consist 



