The wintering areas were surveyed by use of boats, cars, and aircraft 
with the important areas being given aerial coverage whenever possible. Available 
information on number of men, aircraft-involved, and distance covered in the 
survey is presented in the following table: 
No. No. No. 
Pacific Flyway 382 27 . 17,535 
Central Flyway | 262 : 25 20, 060 
Mississippi Flyway 1,965 51 70,578 
Atlantic Flyway 488 | 34 | 30,974 
Total for United States | 2.197 137. 139, 147 . 
Alaska 16 6 3,450 
Mexico 6 2 9,000 
West Indies 2 1 3,000 
Grand Total 2,221 146 154,597 
Breeding Population and Production Surveys 
a a eh Sea Ml li a ai ime nell 
The extensive breeding ground surveys of the past few years have been 
continued. These surveys now include two coverages of most of the important 
waterfowl breeding areas, the first coverage occurring in May for the purpose of 
measuring the distribution and relative size of the breeding population, and the 
second being made during July for the purpose of measuring the production of 
broods. A combination of data from important. breeding areas form the primary 
basis for forecasting changes in the relative size of the fall flight in each of the 
four Flyways. 
The survey methods vary from statistically designed sampling techniques | 
using aerial and ground transects, to censuses of selected sample areas. Aerial 
crews cover the bulk of the breeding range with the various crews sampling in the 
neighborhood of 2,375,000 square miles of waterfowl habitat. For the most part, 
the results of the surveys are presented as "indices to breeding population or 
number of broods.'' The determination of an 'index" figure representing estimated 
breeding population or number of broods has been done for the purpose of estab- 
lishing a basis upon which the results of surveys in one place could be added to 
the results from others. When considering the ''index" figures, however, itis 
emphasized that they do not constitute an estimate of total population. The "indices' 
3 
