18 BULLETIN 191, UNITED STATES NATIONAL MUSEUM 



Mr. Skinner (1921) says that in Yellowstone National Park "nests 

 are built in tall lodgepole pines during early April at from 7500 to 8000 

 feet elevation. They are about thirty feet up, or two-thirds of the dis- 

 tance from ground to tree top, and made of straw placed in the angles be- 

 tween the trunk and a limb about two inches in diameter. The inner 

 nest is mostly of pine needles." 



Alfred M. Bailey tells me that he and R. J. Niedrach found two nests 

 in the mountains of Colorado; one was 20 feet from the ground in a 

 small Douglas fir, at 9,000 feet ; and the other was 25 feet above ground 

 in an Engelmann spruce, at an elevation of 11,000 feet (pi. 4). 



Eggs. — The Rocky Mountain jay seems to lay usually two or three 

 eggs, perhaps sometimes four. These are practically indistinguishable 

 from those of the Canada jay, though some are more heavily marked. 

 The measurements of 20 eggs average 29.9 by 21.7 millimeters; the eggs 

 showing the four extremes measure 33.0 by 24.0, 32.0 by 24.5, and 26.6 

 by 20.0 millimeters. 



Food. — This "camp robber" has practically the same feeding habits as 

 others of the species, frequenting the camps to steal, eat, or carry off 

 almost anything edible. It often does considerable damage to food left 

 in camp or to baited traps. Wilbur C. Knight (1902) writes: "Some 

 years ago while deer hunting we had several carcasses hanging in the 

 trees near by and some quarters that had been skinned. I noticed the 

 birds flying away from the meat whenever I came into camp and upon 

 examining the quarters that were skinned, I found that they had made 

 several holes through the dried surface, large enough to admit their 

 heads, and that they had eaten from each opening from one to two 

 pounds of meat and had entirely destroyed the quarters." 



Mr. Skinner (1921) says: "Truly omnivorous eaters, the Rocky 

 Mountain Jays pick up oats dropped about stables or along the roads ; 

 catch caterpillars, black worms, and grasshoppers ; and once I saw a Jay 

 try for a locust, although he missed and did not try again that I could 

 see." Mrs. Bailey (1928) adds "wild fruits, including elderberry, bear- 

 berry, sumac, and viburnum; also scattered grain in corrals; insects, es- 

 pecially grasshoppers and caterpillars ; small mammals, meat, and camp 

 food." On the Upper Pecos River she (1904) saw them eating toad- 

 stool. 



Mr. Munro has sent me some notes on the stomach contents of Rocky 

 Mountain jays taken in British Columbia. In four stomachs collected 

 on September 20, 1939, one contained seeds of Rosaceae to the extent 

 of 70 percent ; two others contained 70 percent insects, including a large 

 dipterous pupa, parts of two large Diptera, and other insect remains; 



