100 * "Several Thousand" 
00 
500 
200 
100 
000 CENTRAL 
EGG LAYING 
™ Span of dates Ze bd 
100 
29 
JULY x AUG SEP 
2,000 
000 
e 
E. SOUTH : ‘ 
A \ \ I 
200 
cece) 30 OR. 202 SO <) Saeco =) 19 29 fe) 20530 9 IS9= 29 
APR MAY JUN JULY AUG SEP 
ig. 8—Egg-laying and migration seasons of the bank swallow in different areas of the state (see Fig. 1). Spring and fall graph 
(1967-1970) show the highest daily count of each 2 days (left scale). Asterisk symbols represent counts made in other years 
other observers. Shaded areas show the span of dates during which egg laying has been recorded. Dot symbols represent counts 
on the western side of the state; lines without dots represent the eastern side. 
feet, with 2-3 feet being most common. Near laying season from at least May 9 to June 26. At 
Louis, Missouri, Philo W. Smith (unpublished a ‘Tazewell County colony we observed many young 
s) recorded a burrow 6 feet in depth. just ready to fledge on July 31, and John Schwegman 
Ve have insufficient data to construct a quan- (personal communication) saw bank swallows still 
ve curve of the egg laying season, but laying entering their burrows, possibly feeding young, on 
ts from at least May 7 to July 9 in the north August 14 in extreme southern Illinois. There are 
- 8). Much less complete information for cen- no published estimates of nesting success or produc- 
and southern Illinois (combined) indicates a tivity. 
11 
