58 ANIMAL LIFE IN THE YOSEMITE 



The Merriam Bat, smallest of the local bats, is a species likely to be 

 seen by anyone who visits Yosemite Valley or the neighboring country to 

 the west. It appears early in the evening, being usually the first species 

 to be seen abroad, and flies high, in the open air, well above the horizon 

 line. Its flight is notably irregular, even for a bat, and this feature alone 

 often serves to identify a solitary individual when comparisons of size 

 cannot be made. The pipistrelle finds shelter in crevices among the rocks, 

 and of such retreats it has a wide range for choice in the Yosemite. 



On the evening of July 24, 1915, one of our party went bat hunting 

 near Rocky Point, on the north side of Yosemite Valley. The first bat 

 seen, at 7:18, was shot and proved to be a ''pipistrelle." It was flying 

 high in the open among the yellow pines and black oaks, but well away 

 from the foliage of these trees. No other bats were seen that evening until 

 7 :30 when the Large Brown and the Free-tailed appeared simultaneously. 



This bat is evidently resident in the foothill districts throughout the 

 year, as a specimen was shot at El Portal on the evening of January 1, 

 1915. Its continuance in the Yosemite Valley during the winter season 

 seems doubtful; no bats, of any species, M^ere noted there after the end of 

 October. 



At Pleasant Valley on May 22, 1915, a female Merriam Bat was obtained 

 which contained 2 embryos. 



Large Brown Bat. Eptesicus fuscns (Peale and Beauvois) 



Field characters. — Size large, about 3 times that of Little California Bat, and only 

 slightly smaller than Hoary Bat. (See pi. 21d.) Total length 4^4-5 inches (110-124 

 mm.), tail l%-2 inches (47-52 mm.), hind foot % inch (10 mm.), ear i/^ inch (12-13 

 mm.), spread of wings 13l^ inches (337 mm.). Coloration rich brown above, pale 

 brown beneath; flight membranes, ears, and muzzle blackish. 



Occurrence. — Common in summer in Transition and Canadian zones on west slope 

 of Sierra Nevada. Eecorded from Smith Creek, 6 miles east of Coulterville (3000 feet), 

 eastward to Merced Lake (7500 feet). Forages in open sjjaces between trees at 20 to 

 50 feet above ground. 



The Large Brown Bat merits its name both as to size and color, as it 

 is several times as large as the other 'brown' bats (genus Myotis) of the 

 region, and its coloration is a rich brown. Since it is common in practically 

 all parts of the Yosemite region between altitudes of 3000 and 7500 feet, 

 it is likely to come to the attention of visitors in most of the well-known 

 stopping places on the west slope of the mountains. It has not yet been 

 recorded on the east side of the Sierras in the Yosemite section. 



The Large Brown Bat does not come out until some time after the 

 Little California and Merriam bats have begun to fly. In Yosemite during 

 June of 1915 this bat appeared from 7 :40 to 7 :50 p.m., while toward the 



