WESTERN BLUEBIRD 271 



in the draws. As many as four birds were noted hovering and soaring at one 

 time in a few yards of area. 



Dr. Grinnell (1904) describes an interesting method of feeding, as 

 follows: "In Palm Canyon great numbers were in evidence among 

 the giant palms. A dozen or more would be seen clinging to each 

 pendant cluster of dates obviously attracted by the fruity outside 

 pulp. While thus feeding upon the fruit of the palms, the noise made 

 by the seeds dropping into the dry brush at the bases of the lofty 

 trees was so great as to give the impression, before the true cause 

 was discovered, that some large animal was trampling through the 

 undergrowth." 



Grinnell and Storer (1924) give an account of how these bluebirds 

 help to spread the seeds of the mistletoe. Only the soft pulp of the 

 berry is digested, and the seed, which is coated with a film of mucilag- 

 inous material, passes through the bird's alimentary canal in condi- 

 tion to stick where it falls. Should the seed happen to fall on the 

 right kind of host tree, it would, under proper conditions, germinate 

 and start a new plant of this objectionable parasite. The birds swallow 

 so many of these seeds that probably some new plants are started 

 each year. They write of the feeding process: ''The birds individu- 

 ally will seek perches about clumps of mistletoe, either on adjacent 

 parts of the tree or on the twigs of the parasite itself. Berries will be 

 picked off and swallowed in rapid succession. Each bird, as it gets 

 its fill of berries, flies to some nearby perch and sits there quietly. 

 The process of digestion is a rapid one, and before many minutes 

 have elapsed enough of the berries will have gone from the bluebird's 

 gullet into its stomach to permit of further feeding. Thus the day 

 is spent, alternately in feeding and digesting." 



Behavior. — The same authors have this to say on this subject: 



In general demeanor the Western Bluebird is much like other members of the 

 thrush family, being of deliberate or even phlegmatic temperament. When 

 perched it sits quietly, not hopping about as do many small birds such as sparrows 

 and warblers. It ordinarily seeks a perch which will command a wide field of 

 view, as on some upper or outer branch of a deciduous tree. * * * Upon 

 taking to flight bluebirds make off in the open, high in the air, uttering their soft 

 call notes now and then as they fly. The high course of flight and the repeated 

 flight calls are suggestive of the behavior of linnets under similar circumstances. 

 Sometimes the flight is so far above the earth that the birds are quite beyond the 

 range of vision of an observer stationed on the ground, only the mellow call notes 

 giving indication of the passage of the birds overhead. When bluebirds are in 

 flocks the formation is never compact or coherent; individuals move here and 

 there among their companions and single birds or groups join and depart at 

 intervals. 



Voice. — Several observers have condemned the song of the western 

 bluebird with faint praise. Dawson (1923) says: "The Eastern 

 Bluebird warbles delightfully; therefore, the Western Bluebird ought 



