■2 CO Bailey, Birds of the Upper Pecos. LMy 



of the Hudsonian and Alpine zones found on or near the peaks. 

 By reason of our more extended vertical work we were able to 

 throw new light on the distribution of the species noted by Mr. 

 Henshaw, fixing altitudes, and in some instances correcting 

 inferences. 



As the mountains are pointed with peaks reaching up to twelve 

 or thirteen thousand feet, they attract abundant rains and are 

 supplied with innumerable glacial lakes and streams, and con- 

 sequently afford a rich vegetation and a wealth of insect life, 

 which, in turn, support a numerically rich avifauna. Vertically 

 the mountains offer congenial homes for a wide range of species, 

 as they include, from the foothills to the peaks, the Upper 

 Sonoran, Transition, Canadian, Hudsonian, and Alpine zones, 

 with their characteristic trees from low pinones and junipers 

 through yellow pines, spruces and firs, dwarf timberline pines and 

 firs, dwarf willows fruiting at three inches, and finally on the 

 peaks, dense mats of arctic plants. Correlated with the floral 

 zones the birds range from Upper Sonoran Piiion Jays to Alpine 

 Pipits and, in rare instances, Ptarmigan. Species like the Vesper 

 Sparrow and Horned Lark, unusual mountain birds, find suitable 

 homes on the broad, treeless, grassy mesas that, lying above ten 

 thousand feet, extend for miles along the range, for, at this 

 southern end the range is already beginning to broaden out into 

 the Rocky Mountain plateau. 



The exact locality covered by our list of birds is the core of the 

 extreme southern end of the Rocky Mountains, that is, the north 

 and south section drained by the Pecos River, specifically from 

 the source of the Pecos at the foot of the Truchas Peaks south- 

 ward to the mouth of the Pecos Cafion at the village of Pecos. To 

 this is added an east and west section seven miles along the foot- 

 hills on the lower edge of the Transition zone, from Pecos to 

 Glorieta, where the Glorieta divide, on the Santa Fe' R. R., 

 separates the drainage of the Rio Grande from that of the Pecos 

 River. 



The foothill notes in the list that follows were made before 

 entering the mountains, while the mountain list was made, as 

 stated above, between July n and August 24, 1903. 



