swainson's hawk. 75 



Mr. H. W. ITciisluiw givo.s tlic following uole iu refcreiico to the use- 

 fulness of this species : "The crops of all those shot were crammed with 

 grasshoppers; and, as these insects were very abundant, the hawks, as 

 a matter of course, were very fat." (Explor. West of the 100th Merid., 

 Wheeler, vol. v, 1875, p. 422.) 



In a communication from Capt. Platte M. Thorne, dated January 3, 

 1889, from Fort Lyon, Colo., he says : " On July 30, 1S87, shot a Swainson's 

 hawk, which seemed too gorged to fly; stomach contained a great num- 

 ber of large grasshoppers. July 31 shot another whose stomach con- 

 tained part of a gopher and a great many grasshoppers. August 30 

 saw about thirty Swainson's hawks, which were on the ground and 

 apparently feeding. One shot had about as many grasshoppers in the 

 stomach as would fill a tumbler heaping full." 



Mr. Charles F. Morrison, also writing from Colorado, says: "In the 

 fall grasshoppers form the principal diet of this species, although 

 gophers and small birds also are fed upon." (Ornith. and Oologist, vol. 

 XIV, 1889, p. 8.) 



Dr. C. Hart Merriam, in the Forest and Stream of December 27, 1888, 

 page 455, gives a very interesting account of a flock of these birds which 

 he saw feeding on grasshoppers in Oregon in the summer of 1888, 

 which is here added: "During the evening of August 20, 1888, Mr. H. 

 W. Henshaw and I drove from Pendleton to the Umatilla Indian 

 Agency, in northeastern Oregon, about 50 miles east of the G-reat Bend 

 of the Columbia. It had been so hot during the day, the thermometer 

 standing at 104° in the shade, that we were unable to go out. Driving 

 along the crest of the plateau just south of the Umatilla River, at 

 about sundown, we were astonished to see a very large number of 

 large hawks hopping about on the ground, catching grasshoppers. We 

 counted about 150 of these hawks, and there must have been at least 

 200 in the immediate neighborhood. At first we took them to be rough- 

 legs, but later ascertained that nearly if not all were Swainson's hawks 

 [Buteo swainsoni). The period between sundown and dark in that 

 region is so short that the birds were still catching grasshojipers when 

 overtaken by darkness. 



"About 6 o'clock the next morning I visited the same place and was 

 gratified to find the hawks engaged in making their breakfast of grass- 

 hoppers. They were scattered over a larger area than when we saw 

 them the previous evening. Before 8 o'clock most of them had left the 

 hills and settled down for the day in the poplar trees along the river 

 bottom. Here I found the trees literally full of hawks, and counted 

 as many as thirteen in one tree. Two of the three whose stomachs 

 were examined contained grasshoppers and no other food. The third 

 contained, in addition to grasshoppers, the head of a meadow mouse of 

 the genus Arvicola (subgenus GMlotus). One contained 88 grasshop- 

 pers, another 90, and the third 106. Most of the grasshoppers were a 



