and in the same year fully 1,000 dead were reported at Lake Turcott, south- 
east of Alliance. Likewise the death rate was high at Deer and Black Steer 
Lakes, in the same general vicinity, as late as 1937. 
In South Dakota, ducks died from "botulism at Sand Lake, near Columbia, 
in 1935, and 2 years later the disease appeared at Lake Oakwood, in the 
eastern part of the State. In neighboring North Dakota the malady was not- 
ed at Upper Des Lacs Lake for the first time in 1934, when many hundreds of 
"birds died presumably from feeding on decaying insects and other inverte- 
brates washed up on the shoreline. About a thousand died there in 1935, 
and in 1936 an outbreak occurring at the same lake resulted in the death of 
more than 13,000 birds, a loss outnumbering the wild-fowl production of the 
surrounding area for that season. Ailing birds were salvaged, and the bod- 
ies of the dead were buried by crews of CCC boys, while the healthy ones 
were herded out of the supposedly infected areas. Long Lake, southeast of 
Bismarck, a scone of severe mortality in former years, again was the site 
of an epizootic of moderate intensity in 1937.. . 
Two apparently newly infected areas were recorded in Minnesota in 
1937, when certain sloughs in Big Stone County and Lake Shoakatan, Lincoln 
County, were the scenes of botulism outbreaks. "Many hundreds" were re- 
ported to have died in these sections along the western border of the State. 
In Canada 
During the summer and early fall of 1933, it was estimated that 
15,000 to 20,000 ducks and shore birds died at Stobart and Namaka Lakes, 
about 40 miles southeast of Calgary, Alberta, points where there had been 
no previous record of disease. At Stobart Lake sick birds were reported 
in the middle of July by Blackfeet Indians, and the shore line was lit- 
tered with dead by the first week in August. Low water, high temperatures, 
and stagnation characterized the environment at the peak of the outbreak. 
Leeches, in great abundance at Stobart Lake, fastened themselves on the 
helpless birds and were considered by some observers to be the cause of 
the ma.lady. At Namaka Lake, however, where the peak of a similar epizootic 
came a little later, leeches were not plentiful. R. M. Duthie, veterin- 
arian of the Dominion Department of Agriculture, who studied the situa- 
tion late in the course of the outbreak, concluded that it Was "strongly 
suggestive of a toxemia of some kind" and subsequently stated that, although 
certain symptoms characteristic of the disease appeared to be absent, 
botulism may have been the cause. The leeches, he felt, did not play a 
primary role, although it v;as generally admitted that the extent of the 
mortality may have been increased materially by the annelids attaching 
themselves within the air passages and thus strangling the helpless birds. 
At a later time (1936) Shaw and Simpson (3) demonstrated that the organism 
responsible for the outbreak at Stobart Lake was identical with that which 
had caused the extensive mortality in this country. 
Again, in 1934, there was limited early-season mortality among 
Franklin's gulls nesting at Stobart Lake, and later in the year botulism 
reappeared among ducks when the water level had lowered considerably. 
- 5 - 
