92 BIRDS OF COLORADO. 



The narrow strip of country in Colorado where they used 

 to be most common, now contains fully three-fourths of the 

 entire population of the State. The White-necked Raven used 

 to breed from the plains to 6,000 feet, and there is no reason to 

 believe that the few survivors have changed their nesting habits. 

 Its present scarcity can be judged by the fact that of fifteen cor- 

 respondents who have spent a great deal of their time in the field 

 for the last ten years along the eastern base of the mountains 

 from Pueblo to Cheyenne, only two have seen the bird alive. 



488. Corvus americanus. American Crow. 



Resident ; common in northeastern Colorado, rare in the 

 rest of the State. F. M. Dille says in substance of its distribu- 

 tion in Colorado : Breeds in considerable numbers along the 

 courses of the South Platte and its tributaries in northeastern 

 Colorado, although confined principally to the valley of the 

 Platte. Have found it breeding in the near vicinity of Greeley, 

 but from a point eight miles below the town their nests were 

 quite abundant. Five nests found at one time on an island less 

 than two acres in extent. Sometimes after a mild open winter, 

 when the birds had been present in large numbers all the winter, 

 they would disappear entirely as the breeding season approached. 

 The earliest date of a full set of eggs is April i, and the latest 

 date May 23 ; average date April 27. One set taken May 5 on 

 Clear Creek, Jefferson County, and once found nesting almost 

 within the city limits of Denver. (Burns, Bull. No. 5, Wilson 

 Ornith. Chapter Agassiz Assoc. , Oberlin, Ohio.) In the vicinity 

 of Fort Collins the present writer has found them not uncommon 

 during the fall in quite large flocks, and a few nest along the 

 Cache I^a Poudre, east of the foothills. H. G. Hoskins reports 

 having seen seven at various times near Burlington, close to, the 

 Kansas line. Capt. P. M. Thorne saw a few at Fort Lyon, on 

 the Arkansas river, while Drew and Morrison both record it 

 from southwestern Colorado. Breeds from the plains to about 

 7,000 feet and winters on the plains. 



491. Nucifraga columbiana. Clarke's Nutcracker. 



Resident; abundant. The first eggs known to science 

 -were taken by Dennis Gale at Gold Hill March 9, 1888, at 

 8,500 feet;, a second set at the same place April 16, 1889. B. F. 

 GosS had before this, on May 21, 1879, found a nest with young 

 at Fort Garland. Breeds from 7,000 to 12,000 feet, though 

 most commonly from 9,000 to 10,000 feet. Breeds from the 

 first half of March at 8,ooo" feet to the middle of April at its 

 Tiighest range. Only one brood: young are on the wing the 

 latter half of May. Some remain in small parties during the 

 rest of the summer, others gather in larger companies. W. E. 

 D. Scott reports "enormous flocks" at Twin Lakes June 24, 



