10 TBE AjU-D UB O2Ne BU re Eee ieee 
until the incubating bird flew out. Then they would preen a minute and 
fiy away for the feeding and exercise period of about 15 minutes. When 
one returned it was impossible to tell whether it was the same bird that 
incubated before or whether it was the mate; but the same cycle was fol- 
lowed again and again. Toward the end of the incubation period the bird 
on the nest spent less time away from the nest (about five minutes) and 
was fed more often by the mate (once in 15 minutes). 
Chickadee nest in dead stub 
During the first three days after hatching both parents fed the young, 
but after the third day one of the pair disappeared and the other bird 
reared the family of seven by itself. The young birds were naked at birth 
and for three or four days after, except for a little down, and were blind 
and ugly in appearance. They squealed often after the third day and would 
open their mouths wide instantly when I imitated “Phoe-be.” After seven 
days they no longer responded to my call. 
The young chickadees were fed on an average of once every two to 
three minutes during the two-week period when they were developing. This 
agrees with Wilbur K. Butts’ figure of chickadees feeding the young once 
every two and one-third minutes (1931).* This rate of feeding held true 
both when the two birds were feeding and when one was doing all the work. 
During the first six days after hatching the parent stayed on the nest for 
periods of 10 to 15 minutes every hour and then spent the rest of the time 
*A Study of the Chickadee and White-breasted Nuthatch by Means of Marked Indi- 
viduals. Bird Banding, Volume I, 149-168; Volume II, HEPA), aise 
