212 
BULLETIN OF THE BUREAU OF FISHERIES 
Lock Master Huele reported that when the lock was first partly filled with water 
and then emptied in 1915 a large number of drum were carried out; a few days 
later, on March 5, the first complete operation of the season was witnessed, and many 
drum were swept out and caught in hand nets. The fish moved their fins very 
feebly but appeared to be uninjured; the most likely guess is that they were hiber- 
nating and were unable quickly to resume full activity. It seems improbable that 
the temperature in the lock and culverts would be substantially lower than that in 
the river. In 1916, either because the lock had been pumped out during the winter 
or because the first operation was not made until March 24, only a couple of dozen 
drumfish were seen floating. These made frequent efforts to submerge, and some 
of them disappeared, while others quickly floated again to the surface. Fourteen 
drum taken in the lock on this day were dissected and all had the alimentary canals 
empty. No other species was observed to be affected by the filling of the lock. 
Although particularly abundant in the neighborhood of the hydroelectric plant, 
the species is taken in the river generally and by all sorts of tackle. Examples were 
seen each month except December, when no observations were made. 
Figure 30.— Quantities of fresh-water drumfish taken near Keokuk, Iowa, by weeks, May 28 to Sep- 
tember 9, 1916 
A dealer at Dallas City, 111., on the lake, spoke with assurance of spring and 
fall runs of drum, the fall run being then (September 29) expected to occur soon. 
As shown by the reports of local markets, the chief catches during the summer 
months were made in 1916 between July 22 and August 12. The reports, unfor- 
tunately, did not continue beyond September 9. The story for the summer is told 
by Figure 30. With this species, as with some others previously discussed, there 
was no unusual abundance during the spawning season, which evidently occurred in 
June. 
In Lake Pepin, Minn., and Wis., the catch by the seining crew of the Un ted 
States Bureau of Fisheries greatly declined in 1915 and still more in 1916, as appears 
from Table 8. Austin F. Shira, who had charge of the work during a part of the 
period, stated that special efforts were made to secure the fish in 1913 and 1914, 
but the decline was so great as to lead us to suspect that there must be another 
