52 BULLETIN 17 0, UNITED STATES NATIONAL MUSEUM 



watched its parents, set its wings in that direction. There it landed safely, 

 sixty feet above the ground, on a large branch close to the trunk, and was 

 welcomed by its parents. 



Joseph Dixon (1908) took three small downy young duck hawks 

 from a nest in Alaska on June 16, when the largest one was just 

 getting its eyes open. 



He raised them in captivity and weighed them at intervals. On 

 June 19, the smallest one weighed h}{ ounces and the largest 7 ounces. 

 In five days they almost doubled in weight, to 9 and 12 ounces. 

 They weighed 12 and 20 ounces on June 30 and 20 and 25 ounces on 

 July 6. During the next two weeks their plumage began to develop 

 until, on July 21, the largest was "a beautiful falcon with clean 

 bright plumage and a general clear-cut neat appearance"; they 

 weighed 25 and 26 ounces. On July 23, when about six weeks old, 

 the large one was able to fly. "They were not particular as to their 

 food as long as it was fresh meat, except that they preferred bird 

 bodies to mice." 



Dr. Elon H. Eaton (1910) says that sometimes the young "fall 

 from the nesting-shelf and perish on the rocks below." He and his 

 companions had watched an "eyry for 24 hours from a concealed 

 station to observe the visits of the parent falcons. Food was brought 

 only once in this time, and the young birds became unusually rest- 

 less. Finally the male fell over the mountain side and was killed on 

 the talus slope. I believe that the old birds in this case were trying 

 to lure the young from the nest by bringing insufficient food to the 

 ledge. As the young begin to fly the parent birds fly by with prey 

 in their talons, and the young rise to snatch it from them in mid-air 

 as they pass. Thus the weaklings are sometimes left to perish, or in 

 their struggles to obtain the prize meet their destruction. The 

 falcon's eyry must needs be a strenuous school to train the fiercest 

 of all raptores for his murderous career." 



From three nests, in which the date of hatching was definitely 

 known by Mr. Hagar, the first young bird flew from the nest on the 

 33d, 35th, and 33d days, respectively. 



Plumages. — When first hatched, the young duck hawk is rather 

 sparsely covered with short, creamy-white down; when about 10 or 

 14 days old, this is replaced or concealed by longer, thicker, coarse 

 down, pale grayish white above and creamy white below. When 

 about three weeks old, the juvenal plumage begins to appear, and 

 this is completed during the next two or three weeks; the flight stage 

 is reached at an age of about five weeks. The plumage appears first 

 on the back, scapulars, and head ; the wings and tail are sprouting at 

 about the same time. The pectoral tracts are then feathered, and the 

 last of the down is seen on the back, showing through the plumage, 

 on the center of the breast, and finally on the thighs. 



