21U AXIMAL LIl'K IS Till-: YOSIiMlTE 



A nest of the Sierra Chickaree was found at Merced Lake on August 27. 

 1915, the identity being established by seeing the scjuirrel itself visit the 

 place. The nest was located in an old, much rotted and burned out Jeffrey 

 pine stub about 1") feet high and between 5 and G feet in diameter. The 

 entrance to the nest was about 12 feet above the ground, on the north side 

 of the stub, and measured about 2 inches in vertical diameter and 2Vj 

 inches transversely. This entrance hole led into an old woodpecker excava- 

 tion some 6 inches in diameter and 12 or IM inches high. In the bottom 

 of this cavity was about a pint of fine dry material, small chips remaining 

 from the woodpecker tenancy, and twigs, dry grass, cone scales, and 

 squirrel faeces. Prom this old cavity a passageway or hollow place in the 

 wood (of which there were many) led down into a larger cavity 18 inches 

 in transverse diameter and nearly 36 inches in the vertical dimension. The 

 chickaree's nest was in tliis place and to judge from the condition of some 

 of the material the location had been occupied for several seasons or at 

 least for more than one. The total bulk of material which had been carried 

 in by the squirrel was estimated at about 12 quarts. Included were the 

 following items: leaves and twigs of the aspen which had evidently been 

 brought in fresh during the current and previous season ; shredded bark 

 of the aspen ; moss, both green and dry ; staminate cones of lodgepole 

 pine; cores and scales of dissected pistillate cones of both lodgepole pine 

 and Jeffrey pine; mistletoe from coniferous trees; and on top of the whole, 

 as 'bedding,' many freshly cut twig ends of lodgepole pine, with green 

 needles still adhering. These latter varied in length from IVij to 6 inches, 

 averaging about 8 inches. Droppings were found in but one place in 

 the main nest. 



The outer surface of this Jeffrey pine stul) was (piite smooth; yet it 

 offered no particular difficulties to the scjuirrel, which was seen to run 

 down from the top past the hole, then turn around and enter the cavity. 

 Adjacent to the stub was a thicket of aspens and lodgepole pines. The 

 nearest live Jeffrey pine was about 50 feet away. 



On June 2i), 1915, we found a i)laee on the Tioga Road a short distance 

 east of Porcupine Flat where a chickaree had been getting material for a 

 nest. From a slender lodgepole pine about 90 feet high and 12 inches in 

 diameter the s(|uirrel liad cut off numerous terminal branchlets with their 

 adhering needh's, and left them strewn al)out on the ground beneath the 

 tree (i)l. 35/;.) In an area about 15 feet sipiare we counted more than 

 350 twigs, and it was estimated that there were more liian 5()() altogether. 

 The pieces varied from 2 to 12 inches in length, a\'eraging about (> iiudies. 

 None of the twigs, save one or two from which apparently the young cones 

 had been removed, showed any indication tlial they had been worked ujion 

 after being cut olT. ('()mi)arison with other trees in llie vicinity showed 



