The Nesting Habits of the White-tailed 

 Ptarmigan in Colorado 



By EVAN LEWIS 



With photograph? from nature hy the author 



PREVIOUS to starting out to hunt the nest of the Rocky Mountain 

 or White-tailed Ptarmigan in 1890, I had never been in their sum- 

 mer haunts in the nesting season. Having been referred to a man in 

 Denver who claimed to have hunted Ptarmigan at all seasons of the year, 

 he told me there would be no diflRculty in discovering their nests if in a 

 region where they were found in any number. He said they always nest 

 among the small willows that grow anywhere above timber-line. 



As I had seen flocks of over five hundred Ptarmigan at one time on 

 Mount Evans and around Chicago Lakes, that was the ground selected for 

 hunting them. Instead of finding them in flocks, only single pairs were to be 

 seen and in many cases one male or one female. When a male bird was 

 flushed it usually rose with the scream or whistle peculiar to this species. 

 The cry was usually taken up by another male within hearing and in a short 

 time the birds were fighting and chasing each other till one was driven back 

 to his own grounds. The females were seen only near nightfall, either feeding 

 on insects that had fallen during the day on the large snowfields or on the 

 young shoots of alpine clover. This feeding, if on clover, was kept up till 

 it was too dark to follow the bird to its nest; if on insects, the bird usually 

 made a number of quite prolonged flights which carried it safely beyond 

 observation. 



On June 18 a nest was found, the bird merely leaving the nest as the 

 foot was about to fall on it, and in less than fifteen seconds was again cov- 

 ering her eggs. The nest was a mere hollow in the ground that looked 

 like the work of the bird herself. A little dried grass and a few feathers 

 was all that kept bird and eggs from resting on bare ground. Contrary to 

 expectations, there was not a willow within one hundred feet. One or two 

 gnarled pirion trees stood, about fifty feet away. The nest was not round 

 but elliptical in form, and the bird never went on the nest except the long 

 way of the ellipse, sitting facing either the east or the west. 



The search was then renewed and continued till July 7, but on entirely 

 different ground, as the willows were avoided. The result was two old 

 nests of the preceding year, with the egg-shells still in the nest. One of 

 these was on a very small bunch of grass more than half way to the top of 

 what is known as Mount Goliah, just east of Lower Chicago Lake, in a 

 rather deep wash for that mountain ; the grass spot was just out of the way 

 of the water. In this case no willows were nearer than two thousand feet. 

 The other old nest was on the same slope of the mountain, about half a 

 mile farther north. 



(117) 



