material, grass and roots, by the beakful on a young meadow some two hundred 

 feet away; and in the half hour during which I had her under observation she 

 averaged a trip a minute. On the minute schedule she would spend about forty 

 seconds gathering a load and fifteen or twenty seconds in arranging it; but I saw 

 her speed up to twenty and five, respectively. The male, meanwhile, made 

 himself useful by conducting periodical inspections, and offering advice (unheeded, 

 no doubt), but chiefly by mounting guard and chasing off intruders. Needless 

 to say, the birds did not resent my presence, for concealment is impossible under 

 the pitiless glare of a Sierran noonday. 



When we saw a Leucosticte seize a blob of cotton-batting which had blown 

 off our ledge onto the snow, and bear it off in triumph toward a neighboring 

 moraine, we thought that our oological fortunes were made. We dashed after 

 her forthwith; but somewhere near the rocks an aerial scrimmage developed into 

 a quite spirited affair, in which half a dozen Leucos and a snooping Clark Nut- 

 cracker figured. It was all over in a moment; but when the smoke of battle had 

 cleared away, we saw nothing of bird, cotton or nest. A second theft was no 



THE GRAND CIRQUE, LOOKING WEST. THIS IS A TYPICAL FEEDING GROUND 



more successfully traced, for the fugitive had no sooner disappeared around a 

 sharp turn than she gave up all further interest in nest-building. A third, indeed 

 yielded a location; but this was a matter of sheer luck, for the bird used cotton 

 only once, although tempting morsels were, by now, distributed all about the 

 moraines. 



While it is true that the nest-hunter's day is punctuated by such episodes 

 as these, the reader should be reminded that hours of unrewarded vigil precede 

 or follow these occasional flashes of revelation. The rigors of the evening hours, 

 which are the best for observation, are most unrighteously offset by the ardors 

 of midday, when, if one is obliged to be exposed, he feels more like a roasted 

 marmot than a self-respecting scientist. More than once under the intolerable 

 glare I have confessed myself "plumb leucoed", and have beaten for shelter. 



The nests of the Leucos are always fully sheltered. They are set back in 

 niches or placed under boulders, sometimes in chambers of generous proportions, 



17 



