1913 BIRDS OF THE FRESNO DISTRICT 73 



uncommon number especially during- June. Occasionally six eggs are deposited. 



May 30, 191 1, four nests were examined of which the first one held four 

 slightly incubated eggs, another contained large young birds, in the third nesl 

 was a brood of very small birds, while the contents of the fourth proved to be 

 two fresh eggs. 



This species nests most frequently in the willows along canals and ditches, 

 but eucalyptus and cottonwood trees are also often chosen. At least one pair of 

 orioles are almost sure to locate for the summer about nearly every farm house, 

 taking possession of any kind of tree that is to be found there. Some nests are 

 built in upright forks of very small willows in swampy places, but in such cases 

 they are always suspended from small twigs above and are not dependent tor 

 support upon the large branches of the fork, the latter, seemingly, being used for 

 protection from wind and enemies. I have found such nests as low as eight feet 

 from the ground, but the typical nest of Icterus bitllocki is suspended from the 

 extreme tip of a willow branch from tw^enty to thirty feet up, where an examina- 

 tion of the nest is an almost impossible task. 



Nests in this section are composed largely of horse-hair, with string, if it is 

 obtainable, woven into the framework. One or two specimens have been found 

 that were made almost entirely of wild oat heads. 



These horse-hair nests hanging to the leafless branches all through the fol- 

 lowing winter often prove a death trap to other birds, and the writer has fre- 

 quently seen a linnet or other small bird hanging by the neck from an old oriole's 

 nest. Last winter, after much throwing of sticks, my smaller brother and myself 

 brought down such a nest from a height of about twenty-five feet and were not 

 a little surprised to see that the bird, which was suspended by a horse-hair fas- 

 tened securely arovmd its neck, was none other than a Sierra Junco. T do not 

 know how this terrestrial species could have met with such an accident unless it 

 had sought shelter at night in the nest. 



The small yellow butterfly that is found in such numbers in alfalfa fields at 

 certain seasons seems to be especially attractive to the orioles, and countless doz- 

 ens of them are devoured. I have seen this bird in the role of flycatcher at such 

 times, flying from a fence wire and seizing a butterfly on the wing, a rather clumsy 

 efifort but serving the purpose. 



It has been suggested that we cannot count the date of the arrival of this 

 oriole in the spring from the time its note is first heard, unless the bird is actually 

 seen, as the Western Mockingbird is said to imitate the notes in a most deceptive 

 manner just before the orioles arrive. With that thought in mind the writer eager- 

 ly awaited the month of March this year, but failed to prove the correctness of 

 that statement. A pair of Mockingbirds spent the entire winter in the trees along 

 the street near his home and although they were heard singing, more or less, all 

 through the winter, not a single note was heard that in any way resembled the 

 call of an oriole, so I concluded that these particular birds either did not know or 

 had forgotten the oriole's song. Tn view of this fact it seems reasonable to con- 

 clude that even had the notes that were heard on March twenty-fifth proven to 

 have been produced by a Mockingbird it would, nevertheless, have been suf- 

 ficient evidence of the arrival of at least one oriole. 



