WESTERN RED-TAILED HAWK 169 



feet from the ground in a giant cottonwood on the bank of the 

 Columbia Elver in Oregon. It required a vast amount of energy and 

 daring to take the fine series of photographs of eggs and young at 

 different ages that they secured. 



J. A. Munro (1919), referring to the Okanagan Valley in British 

 Columbia, writes : "This is the characteristic hawk of the lower moun- 

 tains. They are equally at home in the dense coniferous forests at 

 the edge of cultivated land, in the open park country of the yellow 

 pine {Pinus ponderosa) or in the midst of deep canyons and rock 

 cliffs. * * * The same nests are used for several years, usually 

 built in tall coniferous trees, forty to sixty feet above the ground. A 

 site commanding a view of open range or valley is preferred." 



W. Leon Dawson (1923) shows a photograph of a redtail's nest 

 only a few feet from the ground in an ocotillo bush; this was in the 

 Imperial Valley desert, where trees are scarce. 



E. L, Sumner, Jr., writes to me of a nest in which the three eggs 

 were surrounded and partially covered by a piece of white w^rapping 

 paj^er; how the paper came there is unknown, but it resulted in the 

 desertion of the nest. James B. Dixon (1902) reports a somewhat 

 similar case in which "the hawks had secured a large piece of barley 

 sack and with this made a lining for the nest, the eggs being covered 

 by it." 



Referring to a thickly populated area in San Diego County, Joseph 

 Dixon (1906) writes: 



We fouud the western red-tail and sparrow hawks and the Pacific horned 

 and barn owls especially abundant. In one valley in a distance of six miles 

 we found twenty-two hawks' nests. Seven of these nests were occupied by red- 

 tails, three by horned owls and one by a red-bellied hawk. Each pair of red- 

 tails usually had two and sometimes three nests, for they seem to occupy 

 different nests from year to year. Two nests were often found built close 

 together and in one instance there were three nests in one clump of trees. 



These twenty-two nests were all located in sycamoi-es which often stood at 

 n bend in the creek or near the edge of the grove. By actual measurement we 

 found that the average height from the ground of twenty-two nests was fifty- 

 five feet. The extremes were seventy-five and forty-three feet. We estimated 

 that there was a pair of hawks to every one-half square mile of territory. 

 What becomes of the offspring in this densely populated district is a problem 

 that I have been unable to solve. But some of them evidently stay near their 

 birthplace, as we found that out of seven pairs, two pairs had moved in since 

 last year. 



Eggs. — The western redtail usually lays two or three eggs, perhaps 

 oftener two ; four eggs are occasionally laid, and five or even six have 

 been recorded. The eggs are practically indistinguishable from those 

 of the eastern redtail, although they may average a little more 

 lieavily marked. The measurements of 48 eggs average 59.2 by 46.4 



83561—37 12 



