142 
3. North San Francisco Bay 
a. Area - 30 Square miles, 
b. Type - Tidal salt marsh, gun clubs, river delta pasture land.. 
c. Coverage - Aerial 10 percent.1950, 15 percent 1951, 15 percent 
1952, 15 percent 1953. 
d. Production summary: 
Estimated Total Nesting Pairs Total Fall Population 
Species 1950 1951 1952 1953 1950 1951 1952 1953 
rr SP, 

Mallard 806 560 480 440 4,000 2, 700 2,460 2, 200 
Gadwall 56 73 130 90 300 350 650 470 
Pintail 9 7 30 140 50 35 150 700 
Shoveler 9 7 10 30 50 40 50 150 
Ruddy duck 74 0 60 90 350 0 300 270 
Others = -“ 140 90 = - 700 27 
Total 954 647 850 880 4,750 3,125 4,250 4, 060 
Goot - - - 250 - - - 1,250 
e. Remarks: Essentially the same as previous years. 
4. North San Joaquin Valley (Grasslands), 
a. Area - 150 Square Miles. 
b. Type - Gun clubs and intermittently flooded pasture lands. 
c. Coverage - Aerial 25 percent 1950, 1951, 1952, 1953, 
d. Production summary: 

Estimated Total Nesting Pairs Total Fall Population 
Species 1950 1951 1952 1933 1950 LOS] 1952 1953 
Mallard 1, 304 1, 703 z2,070 1,420 6, 600 8, 500 10, 350 4,420 
Gadwall 56 192 280 180 300 1, 000 1,400 570 
Pintail 24 100 30 80 150 500 150 330 
Shoveler 8 12 50 200 60 70 250 640 
Redhead 20 88 20 60 100 450 100 190 
Tree Duck 6 0 0 0 40 0 ~ - 
Ruddy Duck 32 28 0 30 180 160 - 100 
Cinn. Teal 76 Be 340 180 500 900 1, 700 620 
Total 1,526 2,295 Zz, 790 2,150 7,930 11,580 13, 950 6, 870 
Coot — 446 724 960 3,900 . 2,000 3,500 4,800 10,770 
e. Remarks: There was a 23 percent decrease in breeding pairs of ducks, 
and a 50 percent decrease in the fall population. Current nesting 
studies (See section on Nesting Studies) indicated a heavy nest 
mortality in the Grasslands area. Coots showed a 300 percent 
increase in nesting pairs and a 125 percent increase in the fall 
population. 
