174 CIVIC BIOLOGY 



Damage annually caused by rats has been figured for several 

 , countries as follows : 



Denmark. . . . ' $3,000,000 



France 40,000,000 



Germany . . 50,000,000 



England . . . ..- . . . , . . 73,000,000 l 



United States 100,000,000 2 



This estimate of $100,000,000 worth of grain is based on the 

 amount actually eaten by rats, and Lantz maintains that they 

 destroy and pollute " fully as much as they consume." But a 



FIG. 83. Common brown rat and mouse 

 Photograph by the author 



damage tax of $200,000,000 levied annually on cereal crops 

 is by no means the whole story. The poultry industry 'yields 

 $600,000,000 annually, and rats take an enormous toll of eggs 

 and young chicks. " I have known them to take nearly all 

 the chicks on a large poultry ranch, and in the same neighbor- 

 hood and over a large territory, to destroy nearly 50 per cent 

 of the season's hatching " (Lantz). The writer learned of an 

 instance of a large rat killing and carrying away an entire 

 brooder lot of over two hundred newly hatched chicks in a 

 single night. Ducks, turkeys, pigeons, game, and song birds 



1 Great Britain and Ireland, rural damage, and does not include losses 

 in towns and cities and that inflicted upon shipping. 



2 For destruction of grains only. 



