300 ANIMAL LIFE IN THE YO SEMITE 



Long-eared Owl. Asio wilsonianus (Lesson) 



Field characters. — Size medium for an owl (somewhat larger than pigeon) ; head and 

 face rounded, with two long ear tufts on top of head just above eyes (fig. 39d, pi. 42a) ; 

 plumage chiefly dark and light brown, in fine complex pattern; eyes yellow. Voice: 

 Of adults, a low, mellow, long-drawn-out hoot, uttered at varying intervals; also, of 

 both adults and young, cat-like calls. 



Occurrence. — Eesident locally both east and west of the Sierra Nevada, below the 

 Canadian Zone. Observed nesting commonly near Williams Butte, and once in Yosemite 

 Valley. Lives in dense tree growths, preferably along or near streams, and forages over 

 adjacent meadowlands. 



The Long-eared Owl seems to be of very local occurrence in the Yosemite 

 region. AVe found it only in Yosemite Valley and in the open country 

 south of Williams Butte. It probably occurs in some numbers to the west- 

 ward also, along the lower reaches of the Merced and Tuolumne rivers ; 

 but we did not happen to see it there. 



"^his owl differs from the other members of its family in the Yosemite 

 region most especially in its choice of a nesting site. Most of our species 

 of owls roost and nest in cavities in trees or in caves in rocks; but the 

 Long-eared Owl finds shelter for itself and its nest in thickets of trees or 

 shrubs on marshy lands or near streams. None of our owls is known to 

 ' build ' a nest in the accepted sense of the word ; they all make use of some 

 existing structure, be it a natural shelter or the nest of some other bird. 



On the floor of Yosemite Valley at late dusk (8:00 and 7:35 p.m.) on 

 the evenings of July 28 and 29, 1915, strange notes having a grating, tinny 

 quality were heard repeatedly. On the morning of July 31, when the same 

 sound was heard in the same locality, a close scrutiny of trees in the vicinity 

 was undertaken, which disclosed the maker of these sounds to be a young 

 Long-eared Owl, chiefly in the grayish down of the natal plumage. The 

 owlet was perched about twenty feet up on a swaying branch of a young 

 incense cedar standing in a dense thicket of the same sort of trees. The 

 empty nest was close by, about thirty feet above the ground in a small 

 yellow pine, and was partly supported by branches of a slender cedar which 

 were interlaced with those of the pine. This was only about 200 feet from 

 the Cooper Hawk's nest discovered a few days previously (see account 

 of that species), and was probably an old nest of that hawk, for it was 

 similarly constructed of coarse sticks. The nest was smeared with excre- 

 ment, indicating that a brood of young had been reared in it recently. 

 On the ground directly beneath the young bird there was a fresh, headless 

 Yosemite Meadow Mouse {Microtus montanus yosemite) and many dis- 

 gorged pellets, while the surrounding ground was splashed with white 

 excrement. 



When Mr. Dixon first arrived at the Farrington Ranch, near Williams 

 Butte, on April 27, 1916, he found Long-eared Owls numerous there and 



