1078 U.S. NATIONAL MUSEUM BULLETIN 237 part 2 



the parents with their offspring. As one hikes through the high 

 country little groups of j uncos fly ahead, alighting now and then in 

 a Douglas fir, limber pine or aspen, then fly again as the hiking party 

 disturbs them. But they do not fly far and do not really seem dis- 

 turbed by human intrusion. I have a suspicion that after leaving 

 the nest young juncos with their parents may make an upward migra- 

 tion among the mountains. Where earlier in the season I found 

 nesting pairs the birds were gone, but in the higher country they 

 seemed more plentiful than before. 



Toward the latter part of August the flocks become larger as family 

 joins family. In August 1960 near the Continental Divide in Clark 

 County, Idaho, I encountered flocks of juncos in quantities beyond 

 counting. Juncos were everywhere, in the open places between the 

 scattered conifers of the hillsides, and among the upturned snags and 

 brush of the shore of a small lake which shall remain nameless because 

 of the huge trout my brother and I have taken there and want to 

 take again. 



Streaked young predominate in the late summer flocks, but the 

 young juncos get their adult plumage within 2 or 3 months 

 after hatching, and the October flocks are nearly all in adult plumage. 



While many remain in the high country as long as possible, even 

 as late as October and November, so far as is known birds of this 

 race migrate completely, and none stays in its snow-covered mountain 

 breeding home through the winter. 



Fall migration is irregular as there are records of juncos migrating 

 or at their winter homes while others are still in the vicinity of the 

 breeding grounds. E. R. Warren (1916) says for the Elk Mountain 

 region, Gunnison County, Colo., that the junco arrives "as early as 

 September 24, and remains throughout October." H. S. Swarth 

 (1908) says "first seen on October 18" in the Huachuca Mountains 

 of Arizona. 



Pink-sided Oregon juncos winter commonly on the lower moun- 

 tains and foothills of Colorado, New Mexico and Arizona. At 

 Boulder, Boulder County, Colo., John N. and Eleanor Hough (pers. 

 comm.) report October 11 as their earliest date in the fall and May 1 

 as their latest date for the years 1946 to 1958. In their opinion "it 

 is certainly the most common winter junco" at Boulder. 



Open or scattered woodland or forest, if that is the term, covers 

 many of the mountains that are winter range for this junco. In 

 southern Pima County, Ariz., A. R. Phillips (1933) says: "Found 

 from the crests of the ridges to the canyon bottoms (of the Baboqulvari 

 Mountains), but commonest in the live oak belt." 



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