358 BULLETIN 17 0, UNITED STATES NATIONAL MUSEUM 



NYCTEA NYCTEA (Linnaeus) 

 SNOWY OWL 



Plates 79-83 

 HABITS 



This great white owl, one of the largest and most powerful, enjoys 

 a wide circumpolar distribution throughout the Arctic regions of 

 both hemispheres. It breeds north of the limits of trees on the 

 Arctic tundras as far north as explorers have found suitable land that 

 is not covered with perpetual ice and snow, and where it can find 

 suitable food supply. But it is by no means evenly distributed or 

 universally abundant, nor is it permanently abundant anywhere, 

 on account of the periodic fluctuations in its food supply. At Point 

 Barrow, for example, John Murdoch (1885) says: "Its abundance in 

 the spring and summer near the coast appears to depend on the pres- 

 ence or absence of its favorite food, the Lemming, as has been noted 

 elsewhere by Mr. Nelson. During the season of 1882 we saw no 

 Lemmings, though signs of their presence in the shape of droppings, 

 and their skulls and skeletons in owl's castings, were numerous all 

 over the tundra. During that season we saw but very few owls. 

 On the other hand, in 1883, Lemmings were exceedingly plenty all 

 round the station, and owls were proportionately abundant; scarcely 

 a day passed without one or more being seen sitting on the tundra, 

 generally on the top of a bank or small knoll, on the lookout for 

 Lemmings.' ' 



Writing of its distribution in Alaska, Dr. E. W. Nelson (1887) 

 says: 



It is more common in the northern part of the Territory, where its distribution 

 however, is irregular, it being abundant at one season and almost totally unknown 

 the next. I was informed by Captain Smith — a well known whaling captain 

 of that region — that he had seen as many as fifty of these birds perched in view 

 at one time along the abrupt coast-line of the Arctic, in the vicinity of Cape 

 Lisburne, and yet they were so shy that it was impossible to secure a single 

 bird. * * * The natives told me of seasons, separated by long intervals, 

 when the lemmings have occurred in the greatest abundance, and the White 

 Owl accompanied them in such numbers that they were seen dotting the country 

 here and there as they perched upon the scattered knolls. 



Theodore Pleske (1928) says of the haunts of this owl on the 

 Eurasian tundra: 



The Snowy Owl during its breeding season inhabits the alpine zone exclusively, 

 that is to say, those parts that are quite bare of any vegetation whatever, either 

 the tops of the mountains (the tunturi of Lapland and the Pae-choi) or the plains 

 of the circumpolar tundra. I believe, therefore, that if these plains are quite 

 lacking in dry hillocks or if they chiefly consist of marshy ground, the Snowy 

 Owl does not readily breed in them and seeks more favorable situations for 

 nesting. Evidently these hillocks are absolutely essential for the existence of 

 this bird because they serve it as observation-posts over its hunting grounds. 



