WILLOW PTARMIGAN 185 



2'hysanura, and 15 other insects and larvae, but no vegetable matter. 

 He says: 



The eight chicks foraged in a loose flock covering an area about five feet wide 

 and six feet long. They pursue small insects and mosquitoes which they run 

 down or reach up for and pick off the grass. I watched one chick catch a 

 cranefly and after hammering and pecking at it awhile he concluded that it 

 was too tough, gave it up as a bad job, and left it. 



Dr. Joseph Grinnell (1900) writes: 



Occasionally a few spruce needles were also found. The gizzards of the 

 birds obtained, invariably contained a quantity of small polished pieces of 

 clear quartz, this probably being the hardest substance for the purpose ob- 

 tainable by the birds. A bare place on a sand-bar in the river, kept clear of 

 snow by the wind, was wont to be frequently visited by the ptarmigan and 

 I have seen them scratching over the gravel in such places, even in the coldest 

 mid-winter weather. 



In addition to many of the above items, E. A. Preble (1903) 

 lists mushrooms, tops and seeds of grasses, and leaves, seeds, and 

 berries of various other plants. 



Behavior. — Ptarmigan rise from the ground with a loud whir 

 of wings and harsh cackling notes. When scattered about feeding 

 among the willows they do not all rise at once but jump up singly 

 or a few at a time, and there are generally a few laggards. When 

 well under way their flight is strong, swift, direct, and often pro- 

 longed for a long distance. They alight readily on trees and bushes, 

 where they are skillful at balancing. In winter it is difficult to 

 see them on the snow-laden branches, where they look much like 

 balls of snow. On bright, sunny days their shadows show up plainly 

 on the snow-covered ground; but on dull, hazy days they are very 

 hard to see, unless the black bill or eye is in motion. The black 

 tail is entirely concealed, except in flight, when it serves as a very 

 good direction mark for other members of the flock to follow. They 

 seem to understand the value of protective coloration, for, if the 

 ground remains bare after the white plumage is assumed, they are 

 very shy ; but, after the snow comes, they become very tame. Grace 

 A. Hill (1922) calls attention to the fact that, while the ptarmigan 

 are molting into the white winter plumage, they frequent the open 

 tundra at the time the cottongrass {Eriophoruvi polystachion) is 

 bearing its white cottony plumes, which aid the birds in their 

 protective coloration. 



Ptarmigan are evidently monogamous and make quite devoted 

 couples. Dixon (1927) tells of a male, perched on the top of a 

 spruce, standing guard over his mate while she was feeding. Mr. 

 Dixon writes: 



The bird gave a couple of warning calls as I approached the tree, and then it 

 dawned on me that he was probably standing guard while his nesting mate 



