CALIFORNIA SHRIKE 169 



for the capture of about 40 percent of the food of tlie family. She 

 still spends much time brooding and occasionally eats food brought 

 b}^ the male, but rarely begging for it. The young may be left un- 

 brooded for periods of 20 minutes, whereas earlier they were left 

 for but intervals of about 5 minutes even at midday. The anxiety of 

 the female to cover the young is regulated by the temperature. Late 

 in the evening attempts to return to the nest v/hile I was weighing 

 the young were more frequent and bold than at midday when tempera- 

 tures were as high as 75° F. 



Brooding still occupies 50 percent of the time of the female on the 

 sixth day. The male and to some extent the female are much more 

 demonstrative against intruders than previously, coming closer and 

 making more elaborate attacks upon them. Frequently adidts have 

 flown at my head, coming within a foot. It has been reported by 

 several competent observers that at times the parent will even strike 

 the intruder during these attacks. Late in the afternoon at one 

 nest tlie young were hungry continuously, opening their mouths in 

 response to nil manner of stimuli and attempting to swallow fingers 

 or even the ^vings of other nestlings that, through jostling, happened 

 to be placed inside their open mouths. Nevertheless, the parent fed 

 but three times in 45 minutes. 



On the seventh day the brood in one nest was banded. The female, 

 when allowed to return, eyed the nest and picked at the bands, soon 

 lifting one of them up as though extracting a fecal sac. Finding the 

 band attached to the young, she made a more vigorous effort and 

 finally pulled the band and the leg up above the rim of the nest. The 

 next effort dislodged the juvenile, and the female started to leave 

 the nest with the band in her bill and the young dangling beneath. 

 She flew only 6 feet in the direction of the customary depository for 

 fecal masses and then fluttered to the ground. Considerable con- 

 sternation was registered by both parents; they inspected the juvenile 

 as it lay on the bare ground and screeched and hovered over it. After 

 10 minutes the female returned to the nest to brood. Fearing that the 

 bird on the ground had been deserted completely, I replaced it in the 

 nest. Subsequently, at each visit to the nest, the female made an 

 effort to remove the bands but never again proceeded so far as to 

 extract a young bird. Finally, after about 10 such efforts at intervals 

 of 5 or 10 minutes, each effort decreasing in intensity, the bird ceased 

 to pick at the bands. Through repeated trial and error she had come 

 to recognize that this type of foreign material could not be removed 

 successfully from the nest. After the juvenile that had been dropped 

 to the ground was returned to the nest, the female several times left 

 the nest and hovered and hopped about the spot where it had been. 

 The inference would be that the shrike does not sense the number of 



843290—50 12 



