5 ® 
n4 
be 
w 
23 ® ® ® ® 
3 
wee . ® ® ® ® 
WW 
= | ® ® e e e e e 
=) 
4 
bq ood 
5 10 15 18 26 30 
DAYS BETWEEN IST AND 2ND NESTINGS 
Fig. 22. — Number of days between the end of the first nesting and 
the beginning of the second nesting of eastern phoebes. Circled symbols 
represent re-use of same nest structure used in first nesting. Dot symbols 
represent new nests constructed near site of first nesting. 
Fig. 23. — Typical eastern phoebe nest in rock niche. | 
24 
yy 
(Table 3), even in second nestings. At a bridge in Clay 
County, where at least three phoebes attempted i 
occupy the same territory, two contemporaneous ne 
were built, one of which received 7 eggs and ultimate 
fledged one young. Two females probably contributed 
the clutch. Clutches of more than 6 eggs are abnorm 
and even 6-egg clutches are uncommon. Though we ha’ 
found many nests with 2 and even only 1 egg, all we 
cases in which predation may have occurred. Phoebe eg 
are usually immaculate white, but some clutches a 
faintly speckled with reddish brown. 
The phoebe is a common victim of cowbird parasitis 
in most of Illinois. Phoebe nests for which we hi 
relatively complete histories showed an incidence 
about 14 percent in the north, where Blocher (193 
