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Estimated Total Nesting Prs. Fall Population Indices 
Species 1952 1953 1954 1955 2 9 
Mallard 3, 640 1,400 500 660 18,100 7,000 2,480 2,740 
Gadwall 480 200 100 140 2,500 1,000 500 690 
Cinn. Teal 580 100 100 140 2,900 460 480 520 
Others 180 140 90 60 900 700 450 300 
Total 4, 880 1, 840 790)=— 11, 000 24,400 9,160 3,910 4,250 
Coots 180 120 100 400 900 600 500 1,840 
e. Remarks: Figures this year indicate a 27 percent increase 
in breeding ducks and a nine percent increase in 
the fall population. Breeding coots increased 
300 percent while the fall population showed a 
268 percent increase. 
3. North San Francisco Bay 
a. Area - 30 square miles. 
b. Type - Tidal saltmarsh, gun clubs, river delta pasture land. 
c. Coverage ~ 15 percent aerial transect. 
d. Production summary; 
Estimated Total Nesting Prs. Fall Population Indices 
Species 1952 1953 1954 1955 1952 1953 1954 1955 
Mallard 480 440 400 80 2,400 2,200 2,000 330 
Pintail 30 140 20 0 150 700 100 0 
Gadwall 130 90 140 10 650 470 700 40 
Cinn. Teal 30 10 30 10 150 30 150 40 
Ruddy Duck 60 90 120 0 300 270 600 0 
Shoveler 10 30 50 20 50 150 290 80 
Others 110 80 0 10 550 240 0 40 
eee ee ee eeeeEeeeeeeeeeeoIeeEe——eE——TT—ETETE—E—E 
Total 850 880 760 130 4,250 4,060 3,840 530 
Coots 0 250 420 140 0 61,250 2,100 640 
e. Remarks: This area shows a considerable decrease in both — 
ducks and coots. The loss of waterfowl habitat 
due to the development of salt evaporation ponds 
is probably causing this decrease. Breeding 
ducks decreased 83 percent and the fall population 
declined 86 percent. Nesting coots decreased 
67 percent and the fall population was down 70 
percent. 
