
Number of Observers Number of Planes Number of 



Location State - Federal State Federal Miles Flown 
Pacific Flyway 343 41 13 12 12, 488 
Central Flyway 327 44 24 ll 16, 943 
Mississippi Flyway 738. 43 11 11 14,070 
Atlantic Flyway 286 31 13 17 21,865 — 
Total for U. S. 1,694 159 61 47 65, 366 
Mexico 1 4 2 9,000 
West Indies — 2 l 3, 000 
Grand Total 1,695 165 61 50 77, 366 
Breeding Population-Production Surveys 
Information derived from surveys on the breeding grounds of 
waterfowl constitute the best basis for forecasting the fall flights each 
year and obtaining an understanding of what it takes to produce waterfowl. 
The surveys have been expanded during recent years until they now include 
coverage of the more important breeding areas in Alaska and the 
Northwest Territories, a sampling of all portions of Alberta, Saskatchewan, 
Manitoba, North Dakota and South Dakota, and coverage of from a few to 
many of the important areas in British Columbia, the Maritime Provinces, 
Ontario, Quebec and approximately 25 States. Methods vary from 
statistically designed sampling techniques, using aerial and ground 
'. transect methods to censuses of scattered sample areas, The only data 
presented here, however, are those which have been taken ina comparable 
manner for 2 years or more, so that a trend in population can be drawn, 
based on quantitative information, 
It will be noted in the following report that "indices to breeding 
populations or numbers of broods'' have been calculated for some areas, 
The calculation ofan "index'' figure has been done for the purpose of adding 
the results of the various surveys together so that one figure can be obtained 
covering wider areas. In-considering the "index" figures, however, it is 
emphasized that they do not represent total populations. Indices are based 
on birds seen, and it is known that when using most census methods a 
portion af the birds are missed, This does not detract from the falue of 
the figures in determining relative changes in population levels from year 
to year, which is the important point so far as management is concerned, 
Every effort is being made to get all cooperators to calculate breeding 
population and production indices, Once this goal is achieved it will then 
be possible to appraise the relative importance of all sections of the 
breeding range and make the forecasts more accurate for the range as a 
whole, 
