TABLE A-16.—Number of birds, by species, northern interior 
of Mexico, winter survey, January 1964 and 1963 
Species 
1964 
1963 
Ducks: 
Dabblers: 
Mallard- 
455 
700 
Mexican duck- 
41 
114 
Gadwall- 
460 
1,637 
American widgeon- 
1,021 
4,383 
Green-winged teal- 
5,804 
27,498 
Blue-winged teal- 
140 
571 
Shoveler- 
2,911 
22,470 
Pintail- 
11,536 
23,706 
Wood duck- 
— 
— 
Tree duck- 
— 
— 
Subtotal- 
22,368 
81,079 
Divers: 
Redhead - 
485 
32 
Canvasback- 
237 
2,128 
Scaup - 
60 
44 
Ring-necked duck- 
390 
652 
Goldeneye- 
35 
— 
Bufflehead- 
31 
30 
Ruddy duck- 
610 
3,095 
Subtotal- 
1,848 
5,981 
Miscellaneous: 
Merganser- 
90 
947 
Unidentified- 
56,994 
31,020 
Total ducks- 
81,300 
119,027 
Geese: 
Snow and Blue- 
22,285 
44,400 
White-fronted- 
6,566 
4,408 
Canada- 
75 
-- 
Total geese- 
28,926 
48,808 
Swans: 
Whistling- 
— 
— 
Trumpeter- 
— 
Coots- 
20,215 
11,349 
Grand total- 
130,441 
179,184 
49 
