238 LIFE HISTORIES OF NORTH AMERICAN BIRDS. 



April 10, tliis being from southern California. Even the numeious records 

 from southern Arizona fail to show a single date earlier than May 12, by far 

 the greater portion falling in the last ten days of this month and the first week 

 in June. These same dates correspond equally well with the commencement 

 of the breeding season in Oregon, Washington, and Idaho, where I took a num- 

 ber of their nests. 



In Wyoming, Montana, the Dakotas, Manitoba, and farther northward, 

 most of the records are in June, a few in July, and a single specimen was 

 taken by Dr. Elliott Coues on St. Marys River, Montana, on August 17, 

 1874, but this was probably an addled egg. 



Swainson's Hawk arrives in its summer home fully a month before nidifi- 

 cation commences, and during this period these birds spend considerable time 

 on the wing, sailing and circling around high in the air, uttering their not unmu- 

 sical notes; at other times they are much more sluggish and are fond of sitting 

 on a dead limb of a tree; a telegraph pole on the plains is a particularly 

 favorite perch of theirs, or a sage bush or some hillock on the prairie, from 

 whence thev watch the surroundings for their humble fare. This latter habit 



tl 



of sitting on the ground is rather characteristic of this species. 



They rarely build a new nest, the one used the previous year, if not 

 already occupied by some of the earlier breeders, like the American Long- 

 eared Owl, Asio wilsonianus, is slightly repaired by the addition of a few 

 sticks and a little lining, or an old Crow's nest is taken possession of and 

 reconstructed to suit; these repairs seldom take more than a day or so, and the 

 nest is then ready for the eggs. The nesting sites of this species vary greatly 

 according to circumstances and locality. In southern Arizona, especially in 

 the vicinity of Fort Huachuca, where this Hawk is a resident and exceedingly 

 common, Lieut. H. C. Benson, Fourth Cavalry, U. S. Army, found forty-one 

 of their nests between May 12 and June 18, 1887. All of these were placed in 

 low mesquite trees, from 3 to 15 feet from the ground. A few found by me 

 near Tucson, in the spring of 1872, were located in similar trees from 10 to 18 

 feet from the ground. 



In southeastern Oregon, as well as in Washington, Idaho, and Montana, 

 I frequently found nests of this species placed in some small bunch of willows 

 growing here and there in marshy places or along the banks of streams, and 

 again in isolated pine trees, straggling patches of junipers, and now and then 

 in mere bushes on side hills of canons, or near the rims or edges of the 

 sagebrush-covered table lands making out from the mountains proper; never 

 in what might be called a forest country. Solitary trees, no matter how 

 small in size, giving a good outlook over the surrounding country, are, in 

 those regions at least, their favorite nesting sites. With but few excep- 

 tions the nests were easily reached and usually placed in a fork close to the 

 main stem, seldom out on one of the larger limbs. Their average height 

 from the ground was not over 20 feet. But a single nest, placed on a large 

 limb of a good sized cottonwood on the Umatilla River, Oregon, of all those 



