6 
tion is concerned. The cities of Milwaukee, Chicago, Detroit, Cleveland, and 
Buffalo are pressed against them. Nearly 53 million people, or 40 per cent of 
the total population of the United States, live in states fronting on the Lakes, 
and about 14 million or approximately 10 per cent in fronting counties. 
Now, what is the status of this important fishing industry? 
During a 40-year period, from 1879 to 1918, these bodies of water 
yielded an average of 101 million pounds of fish annually. Since that time the 
annual yield has fluctuated around 79 million pounds, a decrease of nearly one- 
fourth. The reduction in yield is accelerating with time. The average yield for 
the period 1940-1947 was about 75 million pounds annually, and since then there 
has been a calamitous reduction in catch of the highly prized lake trout. Con- 
cerning this we shall say more later. 
The decline in yield has occurred in the face of an increased fishing 
fleet, more efficient equipment, extension of fishing grounds, the taking of 
rough, less desirable species, as well as the more desirable ones, and a liber- 
alization of restrictions. An example of increased harvesting potential may be 
seen in a comparison of old and new fishing boats. Sailboats of the early fish- 
ery cruised about 10 miles from the shores; present power boats are limited 
in their cruising range only by waters too shallow for their draft. 
If there were an unlimited supply of fish in the Lakes, the annual catch 
should have increased considerably, but this it did not do. Instead it dropped 
more than 22 per cent in the period following 1918. 
The reduction of quantities of the better kinds of fishes resulted in an 
increased demand for the so-called ‘‘rough’’ species. Had this not been the 
case, and had not a substitution of poor for good been made, there would have 
been a further loss of 20 per cent. If we compare the period 1879-1903 with the 
period 1936-1945, this shift is abundantly apparent. The following tabulation, 
by lakes, gives interesting figures on the annual commercial catch: 
Superior, rough fish increased from 20 to 80 per cent of the catch 
Michigan, rough fish increased from 9 to 28 per cent of the catch 
Huron, rough fish increased from 17 to 29 per cent of the catch 
Erie, rough fish increased from 10 to 32 per cent of the catch 
Ontario, rough fish increased from 38 to 60 per cent of the catch 
Two reasons exist for this change: (1) an increase in rough fish pro- 
duction and (2) a decrease in fine fish production. Van Oosten (1949) has 
shown that the greater of these factors has been the loss of fine fish. 
This is enough of statistics, probably, although statistics on fishes can 
hardly be called dry. 
What brought about this drastic resource loss? Specifically, we are in 
