PACIFIC HORNED OWL 337 



present, flapping about from tree to tree and hooting in protest, the 

 nest was empty." 



At another nest in the top of an oak, says Sumner (1929), one 36- 

 day-old owlet "jumped out and flew 100 yards" across the canyon. 

 The two "remaining young are quite aggressive, snapping bills, puffing 

 out feathers, and half spreading their wings in the inverted manner so 

 characteristic of juvenile owls. They sway from side to side with 

 fiercely glaring eyes, and when closely approached throw themselves 

 upon their backs and strike out viciously with their talons, winch are 

 capable of inflicting painful scratches. As soon as I withdraw a few 

 yards, however, they stand upright, hesitating for just a moment as 

 they look about with craning necks, and then commence to flap and 

 hop rapidly toward the nearest cover." 



In a copy of his manuscript notes sent to us, Mr. Sumner says that 

 when he climbed to a nest a "young owl about ten days old greeted me. 

 When put down on the ground in the afternoon sun, at 3 p. m., it 

 panted even though the wind was blowing. Two weeks later this 

 young owl was about quarter grown, with immature plumage feather- 

 ing out all over, bearing on its tips the downs." He says, too, that the 

 nest was becoming foul from old food, bones, fur, and excreta. After 

 the young left the nest, this family kept together for some time. 

 They roosted in the same thicket of low willows for at least two weeks, 

 although Mr. Sumner scared them out every day, and other men soon 

 began using a tractor about 200 feet from the roost. For a detailed 

 study of this subject, the reader is referred to three important papers by 

 E. Lowell Sumner, Jr. (1929, 1933, and 1934). 



The Pacific horned owl, like other horned owls, deposits at the nest 

 various kinds of prey for the young. At first this prey may remain for 

 some time, but after the young are ten days old, this food is cleaned up 

 every day. A list of such prey from many different nests includes: 

 Meadow mice, wood rats, pocket rats, pocket gophers, ground squir- 

 rels, brush rabbits, young and adult cottontail and jack rabbits, kill- 

 deers, shrikes, flickers, jays, band-tail pigeons, coots, and green-wing 

 teals, with rabbits making up fully half of this prey. The item of 

 ground squirrels is interesting because it indicates daylight hunting to 

 capture them. 



Plumages. — The plumages and their development are approximately 

 the same as for other subspecies. 



Food. — The Pacific horned owl destroys many obnoxious forms of 

 life. In addition to the list just given, stomach analyses have added 

 many additional kinds of mice, Jerusalem crickets, and even scorpions. 

 Dixon (1914) says: 



An accurate account of food found in the nest at the time of the various visits 

 gives us the following: parts of two brush rabbits, three wood rats, and five pocket 

 rats. On only one occasion was there any indication of these owls feeding upon 



