PACIFIC FLYWAY 
Winter Trend Data - Pacific Flyway 
As mentioned in the section under Scope of Investigations and 
Methods Used, it was not possible for the Bureau of Sport Fisheries and 
Wildlife to conduct the winter survey in Mexico in January 1957. Since 
there is some variation in the proportion of some species of Pacific 
Fiyway waterfowl that winter in Mexico from year to year, there is some 
question as to the degree to which the data taken in Alaska, Canada, and 
the United States represents trends in the wintering population for the 
entire flyway. This is particularly true with the pintail, gadwall, bald- 
pate, shoveler, green-winged teal, redhead and scaup. Mallards, most of 
the geese, swan, and the bulk of the coot winter in the United States and 
Canada, so it is likely that the data for these species is reasonably 
reliable as indicators of trends in wintering population. 
_ Although it was not possible for Bureau representatives to make 
the regular waterfowl survey at the scheduled time, it was possible for 
waterfowl technicians from California to make a special survey trip in 
February 1957 to census the black brant areas in Baja California (Mexico). 
Tre data for black brant, therefore, are comparable to 1957. 
The percent change in population between 1957 and 1958 is pre- 
sented in the following two tables. ‘The two graphs which follow present 
10-year period 1949 through 1958 based on comparable coverage. 
Percent Change in Pacific Flyway Population Index Figures for Ducks, 
Geese, Brant, Swan, and Coot - Jan 1957 to Jan 1958 
(Comparable ery 


Area, Ducks Geese Brant swan Coot Total 
Alaska { 3 { 2 / 3 
Canada* / 58 - 18 -~ 16 / 48 # 159 ? 64 
Pacific Flyway | 
States ~ 34 #10 - 6 # 16 ~ 16 # 26 
Baja California 
(Mexico ) | - 12 
——— 
TOTAL ~ 34 # 10 - 10 # 16 - 16 # 26 
* British Columbia 
