Nov., 1913 
REPORT UPON DLSEASIi AMONG DUCKvS 
221 
than on the south and east sides. Further, it was out of the question to count all 
the birds on any of the sections between the levees, as part of this territory was in 
heavy mud or under water. But taking into account the ducks on these areas 
and those on the levees, the approximated average for all the territory affected 
was about one to the acre at the very least. Then figuring 25,000 acres as the 
total area of this affected territory, w-e have a total result of 25,000 dead ducks, 
besides many other birds. 
As stated above, ducks on the lake usually prefer to locate for the day on 
the old levees where these are very nearly submerged. Where great 
numbers of birds visited these levees, the latter soon became very filthy. Cir- 
cumstances favored such conditions. The ground was a soft, black mud, full of 
Fig. 72. Diagram showing nature ok country where experiments were carried 
OUT, and observations made, on duck disease at Take Tulare, September 19 
TO October 7, 1913, by the State Fish and Game Commission 
decaying organic matter, consequently when visited iDy thousands of birds, sick 
and well, all paddling together, these levees became very foul. Sick birds, too 
weak to travel, were often found stuck in this mud, or even half buried in it. 
The first symptom of the disease, so far as could be learned, was the loss of 
the power of flight. Following this, the birds became unable to walk. But even 
after losing this function, they were able to swim and dive for several days, some- 
times almost up to the point of death. Paddling in the w^ater never seemed dif- 
ficult, but attempts to dive often failed to take the birds beneath the surface of the 
water. These functions, of course, were dependent on the condition of the birds. 
On becoming very w^eak many of the sick birds took to the levees where they might 
