1090 U.S. NATIONAL MUSEUM BULLETIN 23 7 part 2 



J UNCO OREGANUS PONTILIS Oberholser 



Hanson Laguna Oregon Junco 

 Contributed by James H. Phelps, Jr. 



Habits 



A man, identified only as an American named Hanson and subse- 

 quently murdered, once "tried his hand" at ranching high in the 

 mountains of an obscure corner of Mexico. His name came to be 

 associated, not always with accuracy, with the mountains, the ranch, 

 a shallow lake, and a race of Oregon junco. 



Harry C. Oberholser (1919a) named the race pontilis from juncos 

 E. W. Nelson and E. A. Goldman collected in the Sierra Judrez (or 

 Hanson Laguna Mountains) in 1905, noting: "It has the very pale 

 pinkish sides of Junco oreganus townsendi, but in the color of both 

 head and back is almost exactly intermediate between" thurberi and 

 tovmsendi. 



Contrary to Dwight's (1918) opinion that townsendi was a sub- 

 species of Junco mearnsi, at that time considered a separate species, 

 Oberholser proposed: "The study of these specimens and their rela- 

 tionships with the two contiguous forms shows clearly that Junco 

 oreganus pontilis directly connects Junco townsendi with Junco oreganus 

 thurberi, and that, therefore, the former must be a subspecies of the 

 latter." 



The race is resident and isolated in the nesting season from other 

 juncos, in a single mountain range in the northern part of the Sierra 

 Judrez-San Pedro Mdrtir mountain group of northern Lower Califor- 

 nia, Mexico. According to E. W. Nelson (1922) the Sierra Judrez 

 is a single main ridge about 4,000 feet in elevation at the United 

 States-Mexican border, rising to about 6,000 feet near Hanson Laguna 

 (or Hanson's Lagoon), and decreasing to 4,000 or 5,000 feet at the 

 southern end. The top of the northern part of the Sierra near the 

 type locality of the race at El Rayo (formerly Hanson's Ranch) is 

 no more than three or four miles across. The summit is a long, 

 narrow, rolling plateau, broken by many knolls, ridges of granite, and 

 piled masses of huge, smooth granite boulders, 50 to 300 feet high, 

 between which are small mountain basins or parks and flats. The 

 east face is quite abrupt; the west slope is rolling or undulating. 



According to Nelson's (1922) estimate of the area of suitable com- 

 mercial timber, the available junco habitat along the crest of the 

 Sierra Judrez is no more than 37 miles long by 3 miles wide. A. H. 

 Miller (1941b) says: "Mr. Laurence M. Huey estimates that there 

 is about 20 to 25 miles of scattered Transition Zone forest along 

 this section of the Sierra at elevations between 5000 and 6000 feet. 



