SNOWY OWL 363 



* * * The young, which are helpless at first, are downy white. They slowly 

 become strong enough to stand, and, when they find themselves able to crawl 

 about, they wander among the rocks and grass. * * * With the coming of 

 the fall and winter the family-groups break up, as the individuals seek good 

 hunting-grounds, but the parents may remain together more or less throughout 

 the winter. 



Mr. Miirie (1929) writes: 



As nearly as could be determined the incubation period is about 32 days. * * * 

 When the young were hatched it was the female that fed them, although the male 

 probably furnished the food. Her face and breast were usually bloody and be- 

 draggled as a result of her duties at the nest, while the male's plumage was clean. 

 * * * The longer the nest was occupied the wider and flatter became the cavity. 

 As the young hatched and grew the nest became littered with mouse fur, bird 

 bones, and feathers (including owl feathers). Thus the nest with this accumula- 

 tion in many cases became a mere platform for the young until they were old enough 

 to scramble out and crouch in the grass near by. * * * I was surprised to find 

 a high mortality among the young. Most of the broods numbering 7 or 8 were 

 eventually reduced to 4 or 5, while some were still further decimated. The factors 

 involved are hard to determine, but a number of observations were suggestive. 

 By the middle of July rains had set in and prevailed during the remainder of the 

 season. During the rainy spells I found downy young, in the gray plumage, 

 crouching in the grass, wet and bedraggled. They leave the nest when old enough 

 to scramble about easily and can not then be sheltered by the parents. On July 

 6, in one nest that had been under observation, only one live bird remained and 

 near-by lay two others, dead. On July 15 at another nest the youngest owlet, 

 soaked by rain, was dying. In the first instance feathers of a jaeger (probably 

 Stercorarius parasiticus) were scattered near the nest. The owl may have killed 

 one for food, but it is also possible that the jaeger had attempted to rifle the nest in 

 the owner's absence and had been caught redhanded. Earlier in the season, on 

 May 29, a nest was robbed by jaegers. One egg had been eaten and two or three 

 others punctured, leaving an imprint of the jaeger's bill. No doubt the robbery 

 had been interrupted by one of the parents. 



Plumages. — When first hatched, and probably for the first eight or 

 ten days, the youngest owlets are covered with pure white down. 

 But they soon begin to lose their snowy appearance, as the white 

 down begins to be pushed out and replaced with dark, gray down, 

 thick, long, and fluffy, especially on the flanks and thighs; this is "hair 

 brown" to "drab" and carries on its tips for some time the remains of 

 the primary white down, which gradually wears away. Before these 

 tips have entirely disappeared, the first winter plumage begins to 

 appear in circles of white feathers around the eyes, and on the bend 

 of the wing; the wing quills burst their sheaths at this time, and then 

 follows a general spread of white plumage on the face and wings and, 

 later, on the body, concealing the gray down. 



In their first winter plumage, which is worn until the first post- 

 nuptial molt the following summer, the young birds are much more 

 heavily barred everywhere, than adults of the same sex, with "olive- 

 brown" to "clove brown"; early in the season, at least, and perhaps 



