THE PEST OF BATS 11 



''The brown rat is practically omnivorous. The 

 statement applies as well to the black rat and the 

 roof rat. Their bill of fare includes seeds and grains 

 of all kinds, flour, meal, and food products made 

 from them; fruits and garden vegetables; mush- 

 rooms; bark of growing trees; bulbs, roots, stems, 

 leaves, and flowers of herbaceous plants ; eggs, chicks, 

 ducklings, young pigeons, and young rabbits; milk, 

 butter, and cheese ; fresh meat and carrion ; mice, 

 rats, fish, frogs, and mussels. This great variety of 

 food explains the ease with which rats adapt them- 

 selves to almost every environment. 



"Experiments show that the average quantity of 

 grain consumed by a full-grown rat is fully 2 ounces 

 daily. A half-grown rat eats about as much as an 

 adult. Fed on grain, a rat eats 45 to 50 pounds a 

 year, worth about 60 cents if wheat, or $1.80 if oat- 

 meal. Fed on beefsteaks worth 25 cents a pound, 

 or on young chicks or squabs with a much higher 

 prospective value, the cost of maintaining a rat is 

 proportionately increased. Granted that more than 

 half the food of our rats is waste, the average cost 

 of keeping one rat is still upward of 25 cents a 

 year. 



"If an accurate census of the rats of the United 

 States were possible, a reasonably correct calculation 

 of the minimum cost of feeding them could be made 

 from the above data. If the lyimber of rats sup- 

 ported by the people throughout the United States 

 were equal to the number of domestic animals on the 

 farms horses, cattle, sheep, and hogs the minimum 



