SS se ee eS ee ey 
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 Flyway 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 winter- 
ing population for the entire flyway. This is particularly true with 
the pintail, gadwall, baldpate, 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 to census the black brant areas in Baja 
California (Mexico). The data for black brant, therefore, are com- 
parable to 1956. : 
Percent Change in Pacific Flyway Population Index Figures for Ducks, 
. Geese, Brant,:Swan,:and Coot -:iJanuary 1956 to. January 1957 
(Comparable Coverage) 
Area Ducks Geese Brant Swan Coat Total 
Alaska ; +40 +155 | +50 
Kk | : 
Canada +16 + 95. ~35 ~ 3 +21 +18 
Pacific Flyway : 
States -14 - 22 + 3 - 7 + 6 -12 
Baja California 
~ (Mexico) +54 


Total -14 - 22 +28 ~7 +6 ae 

* British Columbia 
