OL 
NUMBER OF BIRDS (MILLIONS) 
10 
9 
8 ° 
~) 
] . 
NX. } 
yw 
6 Po M/ 
IN ; 

Pacific Flyway 

-—-—— Central Flyway 
2 
0 Re aN a ae ee es eh a 
1949 = 1951-1953 1955 1957-1959 —Ss«1961 
YEAR 
NUMBER OF BIRDS (MILLIONS) 
10 
Mississippi Flyway 

9 —-——— Atlantic Flyway 
8 | 
7 : 
a, 
6 
—— ms 
5 
rN 
/ oN “ 
4 \/7 ‘\ 
y, ‘ 
, \ 
/ 5 
: a’ ‘. 
x ee wt 
2 
1949 = 1951 19953-1955 1957 1959 1961 
YEAR 
FIGURE C-1l.--Trends in numbers of wintering ducks, by Flyways, 1949-61. 
