574 ANIMAL LIFE IN THE YOSEMITE 



which frequented the vicinity and kept voicing disapproval of our actions 

 were shot. Upon dissection the latter proved to be both males! One was 

 undoubtedly the father of the brood but the other was an "innocent by- 

 stander" who fell victim because he had joined in the demonstration. The 

 adults weighed 15.4 and 15.6 grams, respectively, while two of the young 

 birds weighed 14.3 and 14.8 grams. The young at the time of leaving 

 the nest are thus nearly the weight of the parents. 



While as a general rule Plain Titmouses keep to the oak trees, the 

 species sometimes invades the digger pines and occasionally drops down 

 to the brush when foraging. An extreme departure from this habit was 

 noted at the Campbell ranch north of Pleasant Valley, where two of these 

 birds were caught in traps set in a field for the capture of kangaroo rats, 

 the nearest trees being fully 50 yards off. 



Near Coulterville a Plain Titmouse was watched as it went down to 

 bathe one morning in May. The bird descended by short stages to a pool 

 near a small oak, and after arriving at the margin it spent several seconds 

 in looking about cautiously before venturing to flutter its wings in the 

 water. It did not get drenched; few birds do. Of all the birds we have 

 seen bathing in the wild, none get so wet as not to be able to fly readily. 



Short-tailed Mountain Chickadee 

 Penthestes gambeli abbreviatus Grinnell 



Field characters. — About two-thirds size of Junco. Top and back of head, and 

 whole chin and throat, black; side of head below eye and short stripe above eye, white; 

 rest of body chiefly plain gray. (See pi. \Qd.) Manner active and alert; when forag- 

 ing, often hangs inverted from smaller twigs. Voice: Commonest call a wheezy render- 

 ing of the syllables chick-a-dee-dee ; this often shortened to simply chee-chee-chee ; also 

 an alarm note, tsick-a. Song a clearly whistled tee-tee, too-too. 



Occurrence. — Common resident in Canadian and Hudsonian zones, less numerous in 

 Transition; present on both slopes of Sierra Nevada. Recorded from Smith Creek, 

 6 miles east of Coulterville, and from Feliciana Mountain eastward across mountains 

 to Williams Butte and Mono Craters. Lives in trees, mostly conifers, foraging up to 

 50 feet above the ground. In pairs at nesting time; flocking loosely at other seasons, 

 sometimes in company with other small birds. 



The Short-tailed Mountain Chickadee inhabits the whole of the main 

 forested portion of the Yosemite region, beginning at the lower margin 

 of the Transition Zone and ranging up to the highest unstunted trees, at 

 10,000 feet or higher. It occurs on both slopes of the mountains, down 

 on the west to Feliciana Mountain, and to Smith Creek, east of Coulterville. 

 and on the east slope to Williams Butte and Mono Craters. Within this 

 range the species seems to be strictly resident. We found no indication 

 of an up-mountain migration in summer, nor were chickadees noted in 



