THE BROWN RAT 57 



rats in attempting: to escape an enemy will run along a wall or the 

 side of a room with much greater certainty than in the open. 



Food Habits, Economic Importance^ and Control Measures. — 

 Rats are practically omnivorous in diet, and it is in part due to this 

 fact that they are able to maintain themselves under seemingly ad- 

 verse circumstances. The following are some of the principal 

 articles of diet: grain and seeds of practically every variety with 

 the food products made from them ; fruits and garden crops ; bulbs, 

 roots, stems, leaves, and flowers of herbaceous plants ; liark of trees ; 

 eggs, milk, and butter; young chickens, ducks, and other poultry; 

 fresh and decaying meat; mice, rats, fish, frogs, and mollusks. 

 Water is taken in considerable amounts. 



The usual feeding time of rats is after sunset, especially if there 

 is more or less disturbance in the vicinity during the daytime. In 

 situations where they are not often disturbed they will feed in day- 

 light. Cellars of houses and the basements of granaries and cribs 

 are the places often chosen for homes ; and from the burrows which 

 they usually construct in these places the rats make excursions 

 through the buildings at night in search of food. If food ])ecomes 

 extremely scarce the stronger animals sometimes kill and eat their 

 weaker brethren. 



It is estimated that rats cause an annual loss of $200,000,000 in 

 the United States alone. Not only the amount of food actually 

 eaten but also that which is polluted and rendered unfit for use 

 must be taken into consideration ; so that the material losses thus 

 sustained form sufficient argument for the destruction of the pests. 

 The useful work that is done by rats as scavengers is very slight 

 when compared with their detrimental qualities, and there is ade- 

 quate reason for saying that the animals should be exterminated if 

 possible. 



In addition to the food that is eaten and destroyed by rats and 

 mice considerable damage is done in other ways. Stores and ware- 

 houses are invaded and silks, carpets, furniture, furs, leather goods 

 and many other articles are damaged. More than one serious fire 

 can be attributed to rats, because of their gnawing matches or the 

 insulation of electric wires in buildings. Houses are in some cases 

 flooded because the animals have gnawed through lead pipes and 

 occasionally leaks in lead gas-pipes are to be accounted for from 

 the same source. 



