88 PACIFIC COAST AVIFAUNA No. 9 



of May numerous pairs were observed in many of the willow clumps and along 

 the ditches. 



The splendid song of these migrants was much in evidence although the birds 

 themselves were rather shy. So far as could be observed all of these handsome 

 vocalists passed on to a more suitable summer home, none remaining to nest with 

 us. 



Wj<;ste;rn Blue; Grosbeak. Guiraca caerulea lazula (Lesson).* 



While tramping around in late spring among the rank weeds and grass along 

 the ditches or at the edge of tule ponds, a bird-lover in the San Joaquin Valley 

 is often attracted by a sudden explosive "spink" from a large-billed, blue-coated 

 bird, and very often this call is answered in a more subdued "pink" by a orown- 

 colored bird, otherwise quite similar in appearance to her mate. If the date be 

 the 1 8th to 20th of April it is safe to assume that a newly arrived pair of West- 

 ern Blue Grosbeaks have been encountered, for these birds are among the last 

 of our summer visitants to arrive each spring in the vicinity of Fresno. 



The presence of water close at hand seems to be one of the chief requirements 

 of this species during the nesting period. Quite as noticeable is their complete 

 disregard for it after family cares are over, when the grosbeaks seek the dryest 

 grain fields and roadside weed patches, where they may often be seen clinging to 

 swaying wild oats. This plant, together with the cultivated variety, forms one of 

 their favorite foods during the month that they remain in this vicinity after their 

 nesting season terminates, in late June or the first week in July. 



Among the last birds to arrive in the spring, our Grosbeaks are probably the 

 first to depart, and the southward migration begins early in August. Beginning 

 before sunrise on the morning of August 8, 191 1, and for the next two days at 

 least, a migration wave of these birds was observed at Fresno. On the morning 

 mentioned I was attracted by a subdued finch-like song hastily executed, as the 

 singer perched just for a moment on a telephone wire that ran through the outer 

 extremities of one of the branches of a young eucalyptus tree growing in front 

 of my home. Hardly had the song been finished when the bird flew away toward 

 the south, to be followed in a very few minutes by another that went through 

 precisely the same maneuvers, even to perching on almost the exact section of 

 wire that the other had occupied. So far as my observation could determine, the 

 individuals seen on those three mornings were all males. Each one was travelling 

 alone, but was probably keeping within calling distance of another. Although 

 only about a dozen grosbeaks were seen on the three mornings, yet I had reason 

 to believe that many others were passing over the city at the same time. 



Along many of the canals and ditches in the valley grow patches of a plant, 

 the name of which T do not recall, but which greatly resembles in appearance and 

 manner of growth the Chrysanthemum. It would probably be no exaggeration 

 to state that seven of every ten grosbeak nests are built in the clumps of this plant, 

 being fastened to two or three upright shoots in much the same manner that a 

 blackbird attaches its basket-like nest to a bunch of tules. 



When built in such situations the nests vary from six inches to five feet 



^Guiraca caerulea salicarius of Grinnell. See Proceedings Biological Society of Wash- 

 ington, xxiv, 1911, p. 163. 



