OREGON JUNCO 1057 



the species "breeds everywhere, raising three and often four broods." 



Eggs. — Usually four eggs are a set, sometimes three, occasionally 

 five, and an authentic set of one is known. JMilton S. Kay (1919) 

 describes 75 sets totaling 300 eggs of thurberi he collected over a period 

 of nearly 20 years. He says the eggs are: "Usually ovate or rounded 

 ovate, sometimes short ovate, rarely elongate ovate" with a "slight, 

 very slight, or scarcely perceptible gloss. * * * Ground color white, 

 faintly tinged with lichen green * * * spotted and blotched or 

 splashed with hazel, * * * chestnut, * * * and light vinaceous 

 gray * * *." 



Wilson C. Hanna (1924) gives the weight of a set of foiu* Oregon 

 junco eggs. The set averaged 2.08 grams, the largest egg weighed 

 2.15 grams and the smallest 2.00 grams. 



W. G. F. Harris (MS.) thus describes the eggs of the species as a 

 whole; The Oregon junco lays from three to five and most commonly 

 four eggs. They are slightly glossy, and ovate, sometimes tending 

 toward short ovate. The ground is white or very pale bluish-white, 

 speckled, spotted, and sometimes blotched with reddish-browns such 

 as "snuff brown," "russet," "cinnamon brown," "Brussels brown," 

 and "chestnut," with undermarkings of "pale mouse gray." The 

 spottings are generally concentrated toward the large end where they 

 frequently form a wreath. There is considerable variation, some 

 eggs are only sparsely marked while others may be quite heavily 

 spotted or even blotched. The eggs of this species are indistinguish- 

 able from those of Junco hyemalis. The measurements of 142 eggs 

 average 19.3 by 14.6 millimeters; the eggs showing the four extremes 

 measure 21.6 by 15.3, 18.3 by 15.8, 17.1 by 14.9, and 19.3 by 1S.2 

 millimeters. 



Young. — D. S. DeGroot (1934) gives dates that indicate incubation 

 lasts about 13 days. So far as I can determine incubation is entirely 

 by the female. A. H. Miller (pers. comm.) tells me "in the aviaiy, 

 as also in the field, I find that the female alone incubates." 



A. D. DuBois, quoted by A. A. Saunders (1921), tells about a nest 

 in which the eggs hatched May 30 and the young left the nest June 12. 

 These dates suggest the young need 13 to 14 days to fledge. The 

 young left the nest 11 days after hatching in a nest Winton Weyde- 

 meyer (1936) reports upon. 



Irene G. Wheelock (1905) writes that on the day of hatching in a 

 nest she was observing the young were fed 15 times during a 3-hour 

 period in the morning. During the second day feedings were more 

 frequent. She writes: "In two hours, from 9 to 11 a.m., the male 

 came to the nest six and the female eight times. From 1 to 2 p.m. 

 there were 11 feedings." The young were fed both vegetable matter 

 consisting of seeds which she could not identify further and animal 



