88 



NORTH AMERICAN FAUNA 73 



Habitat: Vegetation adjacent to the Douglas County nest was Lowland 

 Coniferous Forest dominated by black spruce, white birch, and green ash. 

 Vast areas of similar habitat exist in southwestern Douglas and adjacent 

 Pine counties. Continued observations in this region may reveal additional 

 breeding records. 



Hawk Owl {Surnia ulula) 

 Status: Casual winter resident. 



Records: Bernard and Klugow (1963) provided the most evidence of hawk 

 owl occurrence in the Valley. They reported three observations of hawk owls 

 in Douglas County including "one bird 5.6 km north of Dairyland (T. 44 N., 

 R. 14 W.), in early March 1963." On 17 March 1963, a dead hawk owl was 

 found 16 km west of Solon Springs (T. 45 N., R. 13 W.) and on 20 March 

 1963 another hawk owl (possibly the first individual) was observed 8.8 km 

 northeast of Dairyland. Other records include one bird collected at Stacy, 

 Chisago County, on 20 October 1962, and two birds observed in Pine County 

 on 17 February 1963 (Green 1963). 



These observations were made during a winter that produced an "inva- 

 sion" of hawk owls in northwestern Wisconsin and much of northern Minne- 

 sota. Later that same year, the nests and young of two separate pairs were 

 found in northeastern Douglas County. The hawk owl is included as casual 

 rather than accidental, because the species is well known for occasional 

 irruptions into southern areas during the winter (cf. Green 1963; Eckert 

 1978). Because large expanses of excellent hawk owl habitat (Lowland Conif- 

 erous Forest) occur in southern Douglas and adjacent Pine counties, I would 

 expect additional records of this owl during future "invasions." 



Boreal Owl {Aegolius funereus) 

 Status: Casual winter resident. 



Records: There are two records for Burnett County: 19 December 1952 at 

 Crex Meadows (N. R. Stone), and 13 April 1975 near the Fish Lake Wildlife 

 Area (W. NorUng). In Pine County, one was observed on 9 November 1972. 



Saw-whet Owl [Aegolius acadicus) 

 Status: Regular migrant and winter resident. 



Migration: Rare migrant throughout the Valley. Spring migrants arrive in 

 mid-March, and most observations occur between 25 March and 15 April 

 (latest— 16 May 1961, St. Croix County). Fall migrants arrive in mid-Sep- 

 tember and most have departed by 15 December. This species is one of the 

 least common regular owls in the Valley. At Hawk Ridge near Duluth, 

 Minnesota, saw-whet owls are the most common migrant owl (Evans 1975). 

 No doubt their small size, nocturnal habits, and very secretive behavior con- 

 tribute to the scarcity of records. 



