414 ANIMAL LIFE IN THE YO SEMITE 



six small young was found on May 22 of the same year. In 1915 the season 

 seemed to be slightly later. Our earliest record of young out of the nest 

 in that year was for May 26, when a fully fledged j'oung bird was observed 

 at Mount Bullion. On May 24 at Pleasant Valley and on May 26 at 

 Snelling adult birds were still concerned with young in the nest. Young 

 birds were seen on Sentinel Meadows in Yosemite Valley on May 31. A 

 set of 4 eggs was still being incubated in a nest on the floor of the Valley 

 on July 10. In 1916 at Mono Lake a nest with fresh eggs was found on 

 May 18. The majority of the broods are probably brought off in the earlier 

 part of the period here outlined. 



Brewer Blackbirds show great diversity in the location of their nests. 

 At Snelling the birds were using planted hedges of the osage orange as 

 well as the native oak trees, and near Pleasant Valley nests were placed 

 in clumps of mistletoe in blue oaks. In Yosemite Valley nests were seen 

 in small yellow pines and in tangles of the cultivated blackberry''. In a 

 meadow near Mono Lake a nest was found at the base of a willow clump 

 and only 4 inches above some standing water. Elsewhere in its range this 

 blackbird often nests at much greater heights above the ground, even as 

 much as 40 feet; but we found none in the Yosemite region more than 

 about 15 feet above the ground. The species never nests in large colonies 

 as do other blackbirds. Occasionally a few pairs have their nests in rather 

 close proximity, but quite as often the structures are placed singly. 



In Yosemite Valley, on June 18, 1915, a nest of this species was dis- 

 covered in a blackberry bush near the Valley schoolhouse. It was situated 

 in a tangle of blossoming branches and well concealed among the leaves. 

 Dried blackberry and weed stems comprised the outer portion of the 

 structure, while the interior was lined with both black and white horse- 

 hairs. The nest measured 7 inches vertically, from base to rim, and the 

 inside diameter and depth were each 31/2 inches. The base was 28 inches 

 above the ground. Four eggs comprised the set ; and 4 to 6 eggs or young 

 were found in the other nests examined by us. 



The Brewer Blackbird is an ardent defender of its home during nesting 

 time, and the members of a pair, often assisted by neighboring pairs, will 

 protest vigorously whenever an animal or person, either intentionally or 

 innocently, approaches a nest containing eggs or young. This was well 

 illustrated by an incident which came to our attention in Yosemite Valley. 

 In a meadow near the Valley schoolhouse, where blackbirds of this species 

 had been found more or less regularly, an unusual commotion was noticed 

 at noon of June 18, 1915. Following up the disturbance it was found that 

 four Brewer Blackbirds were pursuing a California Gray Squirrel. Tlie 

 birds were hovering over the animal, snapping their bills a few inches 

 above its head, and scolding in an angry tone. The s(iuirrel when first 



