196 UNIVERSITY OF COLORADO STUDIES 



Family STRIGIDAE, The Horned Owls, etc. 

 Asio wilsonianus, Long-eared Owl (366) 



Permanent resident; common. Gale took many sets of eggs between April 

 13 and May 16, apparently in the creek valleys in the Yellow Pine zone and at the 

 western edge of the Plains. It occurs in winter on the pine mesas near Boulder. 



Asio flammeus, Short-eared Owl (367) 



Winter resident ; common in the meadows on the Plains. Arrives, September 

 15 — -November 20 (2 records); leaves, February 22— March 31 (3 records). 



[Slrix varia varia, Barred Owl (368)] 



Gale mentions in his notes having seen this species but gives no data. There 

 is but one definite record for the state. 



Cryptoglaux acadica acadica, Saw-whet Owl (372) 



Permanent resident; probably rather common. Gale found several nests 

 with eggs at an elevation of about 8,500 feet; young two weeks old, May 24; 

 fresh eggs, June 3. Sprague reported it from the mountains (Henderson). A 

 specimen was taken by the writer in the lower Yellow Pine, May 15. W. G. Smith 

 found it breeding at Estes Park (Sclater). There are no definite winter records; 

 it has been taken north of the county in winter, however, and probably is a 

 permanent resident. 



Otus asio maxwelliae, Rocky Mountain Screech Owl (373c) 



Permanent resident; common in the Plains zone and along the creeks where 

 they leave the foothills. Gale took many sets of eggs between April 11 and 

 April 21, and stated that he had not observed the species above an elevation of 

 6,000 feet. Pierce (Kellogg) reported it as rare at Estes Park, and Widmann 

 heard several there in July, 1010, at an elevation of 9,000 feet. This subspecies 

 was named by Ridgway from Boulder County specimens in honor of Mrs. Maxwell, 

 of Boulder, who prepared the collection of birds and mammals of Colorado for the 

 Centennial Exposition at Philadelphia. 



Otus flammeolus flammeolus, Flammulated Screech Owl (374) 



Permanent resident. Although this species has been considered rare in the 

 United States, there are more records of its occurrence in the vicinity of Boulder 

 County than there are for either the Pygmy or Saw-whet Owls, and, if it has not 

 been nearly exterminated by the collectors, should be classed locally as infre- 

 quent rather than rare. There was a specimen from Boulder County in the 

 Maxwell collection taken in March, one taken by Gale (Cooke), and one by 

 Sprague, September 22, 1897. W. G. Smith took three female specimens with 

 nests and eggs between June 2 and June 20, 1890, at Estes Park, from 8,000 to 



