1052 U.S. NATIONAL MUSEUM BULLETIN 237 part 2 



mearnsi, oreganus, shufeldti, thurberi, pinosus, pontilis, and townsendi. 

 J. K. Townsend (1837), who described Fringilla oregana, spelled "Ore- 

 gon" with an "a," in common use at that time, and this spelling is 

 retained. Life histories of the races montanus, shufeldti, and thurberi 

 are given in this account; the other races are given in subsidiary- 

 accounts following. The race montanus is known to many as the 

 Montana junco and many references in the literature are cited ac- 

 cordingly; similarly the race shufeldti is known as Shufeldt's junco 

 and the race thurberi is known as the Sierra junco or Thurber's junco. 



In July 1911, J. H. Riley (1912) found slate-colored j uncos and 

 Oregon j uncos nesting together without hybridizing. A. H. Miller 

 (1941b), with more complete knowledge of distribution of the j uncos 

 at his disposal than Riley had, indicates montanus is the race in- 

 volved; RUey says: "Junco h. hyemalis is the common junco east of 

 the main divide, and Junco 0. shufeldti west of it, but we found them 

 both breeding together at Henry House, Alberta, Yellowhead Pass, 

 B. C, and at the foot of Moose Pass, B. C; all of these localities are 

 just over the main divide, either east or west. This convinces me 

 that both belong to distinct species as no intermediates were taken." 



Nevertheless, Oregon j uncos do hybridize with other junco species, 

 and different races of the Oregon junco intergrade with one another 

 where their ranges meet. In some parts of the West as many as 10 

 forms of j uncos may occiu* during migration and the winter season. 

 Hence it is not surprising that their nomenclature has suffered much 

 change and confusion. For a full account of the relationships of the 

 different juncos, see A. H. Miller (1941b). 



Spring. — Of the three races discussed in this account, montanus mi- 

 grates more or less completely, the race shufeldti less so, and the race 

 thurberi partially and, in some cases, not at aU. 



A short dispersal to nearby second growth or cutover timber lands 

 suJQBces for some juncos wintering in the mild Pacific climate; others 

 make a vertical migration from coastal or interior valleys to the higher 

 mountains. Migratory Oregon juncos wintering on the low moun- 

 tains of New Mexico or in the deserts of Arizona have hundreds of 

 miles to go to reach chosen summer homes. 



Where spring migration is noticeable, Oregon juncos appear first at 

 lower elevations and move higher as the season advances. This sug- 

 gests that spring migration follows natural pathways such as river val- 

 leys and mountain passes, pausing if inclement weather occurs. In 

 our intermountain country, with its interesting mixture of isolated 

 mountain ranges and intervening valleys, I have noticed this pattern. 

 On May 10, 1959 several inches of wet, clinging snow covered the low 

 country in our part of Idaho ; snow had melted from roadsides and trails 

 only; higher elevations had more snow. Blaine Lyon and I saw juncos 



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