ARCTIC HORNED OWL 329 



discovered that a pair of these owls had taken possession of an old 

 heron's nest. It was a very large nest, measuring 3 feet in diameter 

 and placed 20 feet from the ground in the dead top of a large cotton- 

 wood tree ; it was well decorated with down and littered with feathers 

 and bones of the owl's victims. There was an occupied heron's nest 

 in the next tree, about 15 feet distant. The single young owl had 

 left the nest and was clinging helplessly in the top of a small sapling 

 nearby; it was nearly fully grown but still unable to fly. We did not 

 see the old owl at first, but I soon saw her coming across an open 

 space, heading straight for me at full speed, as if she intended to 

 knock me over, but she swerved to one side and passed me. 



Frank L. Farley writes to me: "Two nests that I have examined 

 belonging to the Arctic horned owl were both located in heavy timber 

 on the south side of Dried Meat Lake. One of these, found on March 

 17, 1934, contained three fresh eggs. It was built in the crotch of a 

 very large cottonwood tree, about 60 feet from the ground." 



A set of three eggs in my collection was taken by A. D. Henderson 

 near Belvedere, Alberta, on March 20, 1924, from an old hawk's nest 

 in the upright forks of a balsam poplar, at the edge of a small spruce 

 muskeg. It was about 45 feet from the ground; a few fresh twigs had 

 been placed around the edge by the owls, and feathers from the sitting 

 bird had been added. It had snow on it around the edges. This 

 nest was about 400 yards distant from another nest robbed the 

 same day. 



Referring to these and other nests, Mr. Henderson (1925) writes: 

 "From this date forward we were out almost daily and including the 

 nests containing young found seventeen nests of the Arctic Horned 

 Owl. Of many nests of the birds found in the vicinity of Belvedere, 

 only five were in spruce trees and one in a tamarac. The usual location 

 is in an old nest of the Western Red-tailed Hawk, in aspen or balsam 

 poplar trees. Occasionally an old nest of the Crow is used." 



Writing of his work near Fort Simpson, Edward A. Preble (1908) 

 says: "On March 14 I saw a pair in the vicinity of a prospective nest 

 in a high Banksian pine on the hills southwest of the post. The place 

 was again visited April 1 and the female found on the nest. It was 

 left for future developments, but later in the day the tree was cut 

 down by an Indian, and the nest and contents, two fresh eggs, de- 

 stroyed. On April 17 I found another nest near the banks of the 

 Liard, a few miles distant from the post. It was in the crotch of a 

 large aspen poplar, 50 feet from the ground, and held a single egg. 

 It was visited again on April 22, and the two eggs and the male bird 

 secured." 



Eggs. — Mr. Henderson (1925) says: "The usual number of eggs 

 laid is three, but clutches of two and four are also quite common, and 



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