POLICEMEN OF THE AIR 49 



are the only exterminators of locusts. Rodents and 

 other prolific mammals would do untold harm were 

 their numbers not kept down by the bird police. 



A notable example of this kind may be found in 

 the great vole plague in England in 1890-2. At 

 this time the common field-vole multiplied to such 

 an extent that whole districts were threatened with 

 utter ruin. The plague was curbed only by the 

 aid of birds of prey, especially kestrels and short- 

 eared owls. 



Birds also accomplish many other works of na- 

 ture by which the earth and man are benefited. 

 Plant seeds are carried and widely dispersed in the 

 crops, talons, or plumage of most birds. The po- 

 licemen of the air are important agents in these 

 works for the good of all life upon this planet. 



It is unfortunate that only a few rare souls 

 in the human world realise how invaluable to man- 

 kind are these wild creatures of the air, whose equip- 

 ment is unequalled for the part they have to play 

 in keeping nature's balance just. They are the 

 greatest friends of aU farmers, stock raisers, and 

 fruit growers; and they should be regarded as 

 man's most valuable allies, without whose aid agri- 

 culture could not be carried on with great success. 

 The destruction of birds means disaster in the long 

 run. America and England should be justly proud 



