TABLE A-17. --Number of birds, by species, southern interior of Mexico 
winter survey, January 1964 and 1963 
Species 
Ducks: 
Dabblers: 
Mallard- 
Mexican duck- 
Gadwall -- 
American widgeon- 
Green-winged teal- 
Blue-winged teal- 
Shoveler- 
Pintail- 
Wood duck- 
Tree duck- 
Subtotal- 
Divers: 
Redhead - 
Canvasback-- 
Scaup- 
Ring-necked duck- 
Goldeneye- 
Bufflehead- 
Ruddy duck- 
Subtotal- 
Unidentified- 
Total ducks- 
Geese: 
Snow- 
Blue- 
White-frosted- 
Canada- 
Total geese- 
Swans: 
Whistling- 
Trumpeter- 
Coots- 
Grand total- 
1964 
1963 
7,679 
2,820 
5,127 
9,140 
3,291 
12,720 
7,450 
26,400 
24,703 
7,725 
11,009 
2,965 
55,124 
40,560 
— 
70 
114,383 
102,400 
2,090 
__ 
1,055 
1,925 
290 
200 
3,677 
50 
28 
50 
100 
825 
7,240 
3,050 
49.730 
— 
171,353 
105,450 
800 
950 
1,450 
1,400 
2,250 
2,350 
34,475 
20,800 
208,078 
128,600 
50 
