204 
BULLETIN OF THE BUREAU OF FISHERIES 
but the bottoms reclaimed are probably among those that are best adapted as breed- 
ing grounds for the common fishes. It was generally reported in 1926 that black bass 
were notably less abundant than in the years before the development of the Green 
Bay drainage district in 1919, that crappie and bluegills were apparently less affected 
by this development, and that warmouth or goggle-eye were never very abundant. 
SUMMARY AND CONCLUSIONS REGARDING SUNFISHES 
The dam as an obstruction to hypothetical upstream migrations of bass and sun- 
fish may be disregarded. No evidence is found either of any harmful leakage of the 
fish supply of the upper river by the drifting of fish over the dam. The lake obviously 
offers a favorable environment for the reproduction and growth of bass, crappie, and 
bream, but its advantages in this regard are being diminished by agricultural develop- 
ments involving the organization of drainage districts with the construction of levees 
and reclamation of submerged lands. 
THE PERCHES (Percidse) 
The true perches of general interest in the Mississippi River are the yellow 
perch or ringed perch, Perea favescens (Mitchill); the wall-eye pike, Stizostedion 
vitreum (Mitchill); and the sauger, Stizostedion canadense griseum (DeKay). The 
yellow perch was apparently not at all common in the vicinity of Keokuk, but, as it is 
“essentially a lake fish,” it might become more abundant in Keokuk Lake. This 
had not occurred up to 1926. 
The pike perches are locally but inappropriately known here, as in many other 
places, as “salmon” or “jack salmon.” The sauger is evidently much the more 
common of the two pike perches. It was seen at Keokuk each month from February 
to October, but “salmon” of one kind or the other are known to be taken frequently 
in winter, probably more frequently then than at any other season. It is believed 
that most of the winter-caught “salmon” are saugers. Winter fishing is prosecuted 
with hook and line, minnows being used for bait. 
In fact that pike perches are common below the dam in winter suggests the 
possibility of a northward migration. On the other hand, it must be kept in min d 
that the river just below the dam is open in winter when frozen over above and be- 
low, and also that feeding conditions are possibly better there than elsewhere. It is 
said, however, that “salmon” were taken most frequently in winter even before the 
