THE PLAINS AND COLORADO iii 



of prey that fed on field-mice and the smaller 

 mammals at this period during the winter season 

 in New Jersey. This presents a strong contrast to 

 the condition of affairs that now exist. Such a 

 result, the great decrease in the large mouse- 

 hawks, has accrued almost entirely through the 

 systematic persecution to which they have been 

 subjected. They are formidable looking crea- 

 tures, and coming in the classification of the 

 farmer under the head of " hen hawks," they have 

 been treated without mercy. 



It is true that both the red-shouldered and red- 

 tailed hawk make occasional raids on poultry, 

 but these are rare events. Their food consists 

 almost entirely of field-mice and the smaller mam- 

 mals which levy a heavy toll on every stack of 

 grain and every granary, much more than would 

 compensate for the few fowls that the hawks kill. 

 Therefore, the farmer in destroying indiscrimi- 

 nately the larger hawks unwittingly aids in the 

 increase of enemies that, from an economic point 

 of view alone, do him much more damage. 



It is the slim, long-tailed, short, round-winged 

 hawks of the genus Accipiter that habitually 

 prey on smaller birds, poultry, and game. They 

 are not nearly so formidable in size, and are not 

 conspicuous when perching. 



During the summer of 1877 a party of profes- 

 sors and students from the university had made 



