TABLE A-4. --Trend in waterfowl numbers, Pacific Flyway extended, 
winter survey, 1949 to 1964 
[in thousands] 
Year 
Ducks 
Geese 
Brant 
Swans 
Coots 
Total 
1949- 
9,008 
980 
123 
17 
773 
10,901 
1950- 
7,082 
730 
144 
18 
407 
8,381 
1951- 
6,619 
1.000 1 
151 
33 
769 
8,572 
1952- 
6,646 
917 
167 
20 
520 
8,270 
1953- 
7,352 
952 
154 
29 
796 
9,283 
1954- 
7,813 
884 
132 
28 
1,169 
10,026 
1955- 
7,288 
872 
135 
36 
717 
9,048 
1956- 
7,929 
961 
110 
48 
885 
9, 933 
1957- 
6,593 2 
749 
128 
44 
952 
8,466 
1958- 
8,582 
800 
126 
51 
815 
10,394 
1959- 
9,452 
918 
68 
40 
1,007 
11,485 
i960- 
7,760 
883 
105 
36 
859 
9,643 
1961- 
7,780 
1,100 
134 
41 
1,162 
10,217 
1962- 
7,365 
1,223 
170 
34 
703 
9, 495 
1963- 
8,162 
1,081 
140 
47 
605 
10,036 
1964- 
7,572 
985 
185 
30 
755 
9,527 
Note. —Coverage during the period was not comparable and the data were adjusted, using 1959 and 1955 
as base years. It was assumed that areas where comparable surveys were conducted provided an accurate 
measure of the percentage change between 2 consecutive years. On this basis, population estimates were 
calculated backward and forward from the base years. The 1962 figures are based upon only observed birds 
and are not adjusted. 
"'index arbitrarily reduced from 1, 797, 000 to 1 million geese. During January 1951, more geese were 
estimated to be in Merced County, California, than were in the entire Flyway either the previous or the 
following year. It seems certain that the estimate was in error. If the geese recorded in Merced County 
are deleted from the totals for 1950, 1951, and 1952, and a revised estimate is calculated based on change 
observed in the remaining areas, the index for 1951 is about 1 million birds, 
o 
No surveys were conducted in Mexico in 1957. The data indicate that it is unlikely that surveys in the 
United States, Canada, and Alaska accurately revealed the trend in wintering populations of ducks that year. 
40 
