PLATE Xiil 
SEASONAL FLUCTUATIONS IN BROOD 
POPULATIONS BY AGE CLASSES 
BLUE-WINGED TEAL 
(BALOPATE 
BROOD-DAYS PER EIGHT DAY PERIOD 

SHOVELLER 

DATE 6/18-6/26 6/26-74  7/4-7/12 712-720 720-728 /28-8/5 8/5-8/I3 8/13-8/2I | 
Pere Re 
WG AGE CLASS |, EEE 
re 
acta tne ieee at ef 
AGE, CLASS ||. EEG AGE CLASS IN MIL UNAC ED coone 

