412 ANIMAL LIFE IN THE YOSEMITE 



1916, males were present and well established at El Portal. During May, 

 1915, and a^ain in 1919, the species was much in evidence at our camps 

 in the foothills. But as the season advanced the birds became less and 

 less conspicuous. Our latest record is for August 17, 1915, when a single 

 bird was seen from the window of a train while near Pleasant Valley. 

 East of the mountains, the first migrant for the season of 1916 appeared 

 near Williams Butte on May 8. 



In striking contrast to the behavior of the blackbirds, to which it is 

 not distantly related, the Bullock Oriole is, at least during its stay in 

 our latitude, a non-flocking species. Each pair nests by itself and each 

 male presides over a certain rather definite tract of country. 



The song of the male Bullock Oriole, as intimated in the small-type 

 paragraph above, is not readily transcribable. The result of an effort 

 to render the song in syllables is included in the following notebook entry 

 by the junior author written on April 27, 1916, at El Portal : 



Seated under some blue oaks I am listening to several Bullock Orioles. Four males 

 are spaced about 50 to 100 feet apart in four large oak trees, and each at intervals 

 utters his song. The song goes about as follows: chuclif-atd-chuclc, chuck' dta- chuck, 

 ta-wee'-tdh. Intervals between songs are filled with a variety of other notes. A 

 scolding chuc¥-dtd is often uttered continuously for several seconds. Sometimes this 

 is reduced to chu, chu, chu. Also there is a single explosive note, kleek. This last 

 corresponds to the 'chiicJc' of the Western Meadowlark. The female scolds in a minor 

 key. 



Near Blacks Creek, west of Coulterville, a nearly completed nest of 

 the Bullock Oriole was found on May 10, 1919. The nest was ensconced 

 in the crown of a blue oak which stood beside the main traveled road. 

 The female was doing all the work of building, but her mate stayed within 

 200 feet of the nest, flying to and from the site at frequent intervals. 

 There were several clumps of mistletoe in this and adjacent trees, but the 

 nest was not hidden in one of these as is often the case with this oriole. 

 To a passer-by the nest might, indeed, at first glance, as seen against the 

 sky amid the oak foliage, have been mistaken for a small clump of the 

 mistletoe. The female was seen to approach the site with a straw in 

 her bill and then to proceed to incorporate it into the structure. She 

 carried the straw inside and there worked it among •the grasses already 

 in place. Then she emerged and worked on the outside for a time. The 

 whole structure shook visibly as a result of her energetic efforts. On 

 another occasion when bringing material the female caught sight of the 

 observer. She stopped short and scolded several times, still retaining 

 the straw in her bill. Near Sneliing on May 27, 1915, a nest of the Bullock 

 Oriole was seen in a blue oak. 



