
TABLE C-6. --Distribution of wintering waterfowl, Central Flyway extended, 1956-61 
[Index numbers] 




























































































wenn nen ee ---------------= 53,454 80,087 110,461 127,791 74,331 89,009 
North Dakota--------------------- 3,165 7,485 34,041 2,100 31 2,127 
South Dakota--------------------- 56,183 354, 898 1,361,951 605 , 243 93,638 353,967 
Wyoming-------------------------- 65,700 85,794 67,246 75,700 79,662 51,620 
Nebraska------------------------- 230,057 363,248 589,858 331,855 306,412 204,039 
Colorado----------+-----+---------- 283,266 583,326 722,718 473,669 437,045 387,710 
Kansas--------------------------- 273,163 405,132 643,340 355,447 379,557 492,326 
New Mexico-------------- o-------- 114,892 145,636 103,440 143,111 82,373 93,343 
Oklahoma------------------------- 117,113 62,851 124,825 193,685 114,211 106,278 
i i aleslateaiaaiatahatanataiatetahelaatenaaeebetatatae 5,328,771 1,633, 846 3,581,556 3,675,032 | 2,384,384 2,109,680 
co: 
East coast-------------------- 2,070, 750 1,609,110 1,268,048 817,896 1,344,340 
Central------------------ eo--- 945,204 546,637 1,097,771 518,181 522,803 
Central America--------=-------- =e -- -- 28,470 -- 
Northern South America---------- 475,254 
Total-s2n-----s- nnn nna === 
Comparable coverage: 
1956-195'7---2------- 2-2-2 -2~-~ 3,631,478 -- ata -- 
1957-1958---~-------------+--- 3,696,773 7,057,996 is -- 
1958-1959--------=------------ 9,495,183 8,263,472 -- 
1959-1960--------------------- 8,334,711 5,268,271 -- 
1960-1961-------------------+-- “= 5,271,839 5,689,872 
TABLE C-1.--Trend in waterfowl numbers, Central Flyway extended, winter survey, 1949-61 
[In thousands] 
196 law nee eee ee ene eee = weten 

Note,.--Coverage during the pericd 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. : 
1 No surveys were conducted in Mexico in 1957. The data indicate that it is unlikely that surveys in the United 
States alone accurately revealed the trend in wintering population for either ducks or coot that year. 
65 
