70 PACIFIC COAST AVIFAUNA No. 14 



l;i5. Bubo virginianus pallescens Ktoiie 



Western Horned Owl 



A common permanent resident throuwliont the state, except perhaps the 

 northwestern part, where it is {)robal)l.v rriilaci-d, in the mountains at least, by 

 sdtKrains. Tliis species ranges over prairies, valleys and mountains, but it is 

 decidedly commoner in the prairies and valleys. It is l)econiing rare in th'' 

 more thickly settled regions. Nearl.y all observers record it. 



This species nests early in the year. Two sets, of three and four eggs, re- 

 spectively, were taken at Lewistown, March 16, 1900 (Silloway, lOOld, pp. 97- 

 98), and a second set of two eggs, on April 13, 1900 (Silloway, 1903a, pp. 34-35). 

 Young on the wing were noted at Choteau in May, 1912 (Saunders, 1914a, p. 

 132). 



136. Bubo virginianus subarcticus Iloy 



Arctic Horned Owl 



A rare winter visitor tlu'oughont the state. Of twenty-eight birtls from 

 Foi\ Custer in the winter of 1884-85, two approached this form (Bendire, 1892, 

 |ip. 385 and 387). Thorne records this subspecies as common at Port Keogh. 

 adding the statement that some breed (1895, p. 214), which seems extremely 

 doubtful. A specimen taken at Miles City, January 15, 1900 (Hedges, coll. 

 Univ. Mont.). A very rare winter visitor in (he Bitterroot Valle.y. Two at Cor- 

 vallis in the winter of 1907-08 (Bailey, ilS). This last is the only record from 

 the western jiart of the state. 



137. Bubo virginianus saturatus Ridgway 



DnsK'j- II()KNKi> Owl 



Found regularly in the mountains about Kalisp(^ll, where it is a permanent 

 resident. Mr. II. P. Stanford has moiuited a. number of specimens. It is prob- 

 ably the regular form in the northwestern part of the state, at least in the moun- 

 tains, but data on which to determine this with certainty are lacking. Flathead 

 Lake specimens are listed as pallescens (Silloway, 1901a, pp. 48-49), and the 

 horned owl which is a common resident in the Bitterroot Valley (Bailey, MS) 

 has not been iiientified as to subspecies. 



138. Nyctea nyctea (Linnaeus) 



Snowy OwIj 



An erratic and usuall.v rare winter visitor, occurring throughout the state. 

 This species has been recorded by nearly all observers whose work covers periods 

 in the winter. It is found chiefly in the valleys and on the prairies. Silloway 

 states that it occurs from the first of November to early March (1903a, p. 35). 

 The only other dates to indicate the time of its migrations are October 26, 1908, 

 in Tom Minor Basin. Park County, and October 14. 1917, at Kalispell (Sloan- 

 aker, MS). 



