TOLMIE WABBLER 535 



1920 Mr. C. W. Michael (MS) observed the species in Yosemite Valley 

 on September 28. 



The Tolmie Warbler population is not distributed so uniformly as that 

 of certain other species, so it is more difficult to form a general estimate 

 of the numbers. In the snowbush and huckleberry oak on the high plateau 

 above the Valley between Indian Caiion and North Dome, 6 or 7 were noted 

 in a 31/2-liour census, on June 24, 1915. Four or five singing males were 

 recorded along the short trail between Camp Curry and Happy Isles on 

 May 17, 1919. These counts were made in favorable territory ; elsewhere 

 the species is much less frequently encountered. 



Most of the activities of the Tolmie Warbler are carried on within the 

 cover of the brush. Yet in the late spring and early summer months the 

 males not infrequently fly up into adjoining trees and sing from perches 

 well above the ground. At Hazel Green, on May 14, 1919, a bird was 

 observed fully 50 feet above the ground on one of the lower branches of 

 a large incense cedar. The tree stood directly over a seepage slope covered 

 with creek dogwood, which had evidently been chosen as headquarters for 

 the summer. This bird sang ten times in two minutes, changing position 

 usually after singing twice on one perch. The song wa.s rendered by the 

 observer sizik, sizik, sizik, lipik, lipik, little change being detected in suc- 

 cessive songs. In the first three 'words' the 'z' sounds were strong, whereas 

 the last two were more liquid. In singing, the bird would throw its head 

 back, and put much bodily effort into the process of utterance. Soon the 

 bird dropped close to the ground and sang from within the shrubbery, 

 changing his position frequently. The sharp tsip of the female was heard 

 at this time. After a few songs the male flew up to a perch 30 feet above 

 the ground, sang twice, and then went below again, this time into a tangle 

 of small young incense cedars. 



Other individuals studied and timed while they sang gave their songs 

 at intervals of 10 to 14 seconds. Song production is not continuous, how- 

 ever, for at times a bird will be silent for a minute or more. Some males 

 seem to keep entirely within the shelter of the brush, where they alternately 

 sing and forage. 



The 'z' sounds heard from the bird at Hazel Green are entirely lacking 

 in other songs studied. Two of these clearer utterances we wrote as 

 follows: syr-piV , syr-piV , syr-piV , syr-sip-sip-sip-sip (J. G.), and another 

 cheek-a, cheek-a, cheek-a, cheek-a, chee-e-e-e (T. I. S.). The first syllables 

 are loud, clear, and set off from one another, while the shorter ones (sip) 

 are given rapidly, faster than a person can pronounce them, and some- 

 times are run almost into a trill. 



Our earliest record of nesting for the Tolmie Warbler is for May 22 

 (1919) when a completed but empty nest was seen in a thicket of choke- 

 cherries along Redwood Lane in Yosemite Valley. The rim of this was 



