3C6 ANIMAL LIFE IN THE YO SEMITE 



The discover^' of the Great Gray Owl in the Yosemite section was one 

 of the notable events in our field experience. And what was most sur- 

 prising was the fact that the bird was apparently quite at home, and 

 nesting-. No previous record of the breeding of this northern species of 

 owl south of Canada is known to us, and its occurrence even as a winter 

 visitant within the northernmost of the United States is not frequent. 



On June 18, 1915, we were camped to the south of Yosemite Valley 

 on the Glacier Point road within two miles south of Ostrander Rocks, A 

 long trap-line beginning at camp led up the gentle slope toward the latter 

 landmark and through a fine forest of red fir. During inspection of this 

 line on previous days we had distant glimpses, morning or evening, of a 

 large bird in silent flight among the trees. On the day of discovery, however, 

 the diminutive kinglet pointed the way and really deserves all the credit. 

 From a distance through the forest came the low but insistent wer-rup, 

 wer-rup, wer-rup of a Ruby-crown, its unmistakable note of anxiety. The 

 clue was traced by the expectant naturalist to a tall fir, out from near 

 the summit of which there presently flew a great owl. The bird alighted 

 at the top of a Jeffrey pine close at hand where it was shot and wounded. 

 As it fell to the ground it gave several deep-pitched ivJioo's. At this, 

 another owl appeared in flight from one fir top to another and was also 

 obtained. 



We wanted to photograph it, so the wounded bird was taken back to 

 camp alive. Its huge facial discs (pi. 43c), each centered by a great yellow- 

 irised eye, its snapping bill, and its spasmodically clenching claws, all 

 contributed to profound respect on our part in the necessary handling 

 incidental to taking the pictures. 



On succeeding days a careful search of the vicinity was made, and a 

 large nest of sticks, which, it was thought, belonged to the owls, was found 

 one hundred feet above the ground on the close-set branches of a fir next 

 to the trunk. But no close examination of it was made. On June 19 in 

 the same stretch of woods the deep notes of an owl were heard three times 

 repeated, but the bird could not be located. This time the kinglets 

 failed us. 



The two specimens obtained proved to be male and female, probably 

 a mated pair. As is usual with owls the female was slightly the larger, 

 measuring: total length 595 millimeters (nearly 2 feet) ; expanse of wings 

 1370 millimeters (41/2 feet). The male measured: length 580 millimeters; 

 expanse 1350. In both birds the iris was bright straw yellow ; bill greenish 

 becoming yellow toward tip ; claws lead-color darkening toward tips. The 

 stomach of each bird was empty. 



As an indubitable indication of breeding during the current nesting 

 season, the female was found to have a large bare tract on the lower surface 



