A number of the ducks, alive but helpless, were collected on 
the Tule Lake Marshes and carried to pens, where they had access to 
an abundance of fresh, clean water. Many recovered under this treat- 
ment and were liberated. 
During the last of October many sick and dead birds also were 
found in the Sacramento Marshes near Gridley. For miles in the 
sloughs and flats along both sides of the Snake River in southern 
Idaho and across into extreme northern Utah, an outbreak of duck 
sickness, causing the death of many birds, was reported during the 
late summer and early fall of 1925. A report has been received from 
Torreon, on the Mexican tableland, stating that an outbreak of sick- 
ness among the ducks frequenting the flooded cottonfields in north- 
eastern Durango was causing the death of many birds during the season 
1925-26. 
The excessive mortality of wild fowl from alkali poisoning on 
the Bear River Marshes, Utah, a few years ago, and also that about 
Buena Vista Lake, California, before it became dry, as well as the 
occurrence of sickness among these wild fowl in various other lo- 
calities were unquestionably induced by unusual concentrations of 
these birds in limited pools, with the disappearance of the vast 
water areas formerly available for them. The duck sickness at 
Malheur Lake, in eastern Oregon, and Tule Lake and the Sacramento 
Marshes, in northern California, during the fall of 1925, can not 
well be attributed to alkali poisoning, since the waters frequented 
had not, so far as can be learned, sufficiently strong concentrations 
of alkali to affect the birds in the same way as on the Bear River 
Marshes. A sample of the Tule Lake water taken at this season shows 
that it carried a very moderate proportion of alkali and other salts, 
a quantity insufficient to poison the birds. 
Apparently where waterfowl are overcrowded they are developing 
a sickness that may be somewhat akin, if not very closely related, to 
the cholera afflicting domestic fowls. Through the Biological Survey, 
the Bureau of Animal Industry, and the Board of Fish and Game Com- 
missioners of California, investigations were begun to ascertain the 
true cause of the sickness in that State, but the matter was under- 
taken too late in the season, since after a heavy rain the malady dis- 
appeared. Close attention will be paid to this subject during the fall 
of 1926, and every effort will be made to have a competent bacteri- 
ologist study the matter with a view to obtaining information on which 
constructive remedies may be based. It is obvious, however, that until 
 
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