CASSINS KINGBIRD 71 



distribution over the two California deserts, and in the lowlands 

 of the San Diego-Santa Barbara region." 



Courtship. — ^The only reference I can find to what might be called 

 a courtship activity is the following observation by Dr. Wetmoro 

 (1920) at Lake Burford: "This Kingbird was first observed on May 

 25 and from then on it was fairly common. * * * Males were 

 seen at intervals in craz}' zigzag sky dances made to the accompani- 

 ment of harsh calls and odd notes, similar to those of none of our 

 other birds. Toward dusk they called constantly their harsh, 

 stirring notes making a pleasing sound that mingled with the songs 

 of House and Rock Wrens, the scolding of an occasional Mockingbird 

 and the cheerful calls of the Robins." 



Nesting. — Major Bendire (1895) writes: 



The trees generally selected bj' this species for nesting sites are pines, oaks, 

 Cottonwood, walnut, hackberry, and sycamores, and the nests are almost 

 invariably placed near the end of a horizontal limb, usually 20 to 40 feet from 

 the ground, in positions where they are not easily reached. All of the nests 

 examined by me were placed in large cottonwoods, with long spreading limbs, 

 and were saddled on one of these, well out toward the extremity. The majority 

 could only be reached by placing a pole against the limb and climbing to it. 

 They are fully as demonstrative as the Arkansas Kingbird when their nests are 

 disturbed, and are equally courageous in the defense of their eggs and young. 

 The nests are large, bulky structures, larger than those of the preceding 

 species, but composed of similar materials. An average nest measures S inches 

 in outer diameter by 3 inches in depth. The inner cup is 314 inches wide by 1% 

 deep. Sometimes they are pretty well concealed to view from below, but they 

 can usually be readily seen at a distance. 



iMr. Dawson (1923) noticed, in California, a close association with 

 the Arkansas kingbird: 



[In a] region of scattering oak trees and of stream beds lined with cotton- 

 woods, both birds are exceedingly common. As surely as a pair of oak trre.s 

 boast some degree of isolation from their fellows, one will be occupied by a 

 pair of Cassin Kingbirds and the other by a pair of Westerns. Or if the trees 

 are only members of a series, next door neighbors will be occupied by these 

 paired doubles: and the group may be separated by an interval of a hundred 

 yards or so from the next quartet. The arrangement is evidently studied, end 

 it must be mutually agreeable, for the two species are on the best of terms, pnd 

 I have never s«'(>n evidence of jealonsy or ill-will on the part of either. tiiou<jh 

 I have camped right under their nests. 



In the Huachuca and Catalina Mountains, the Cassin's kingbirds 

 showed a preference for the sycamores in the lower canyons, and for 

 the evergreen oaks on the foothills. But near Tombstone, Ariz., my 

 companion, Frank Willard, found a nest 10 feet up in a slender 

 willow and another 8 feet from the ground in a small walnut tree. 

 In California nests have been found in blue-gum trees and in box- 

 elders. Robert B. Rockwell (1908) found nests in Mesa County, 



