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BULLETIN OF THE BUREAU OF FISHERIES 
The only break in the steady decline is found in the returns for 1903 in each 
case. State laws for conservation of game fishes have, no doubt, had a marked 
effect on the commercial fishery for these species. We can offer no other explana- 
tion for the decline except as it may be found in the changed conditions of our streams 
in consequence of the development of the country. 
SUMMARY 
Of the perches, only the sauger (locally known as “salmon”) has any evident 
significance in the river at Keokuk. It is the most prized of local game fishes and 
is taken most frequently in winter by hook and line just below the dam. There is 
slight evidence of a developing commercial importance for the sauger in the lake. 
We have no adequate information regarding the possible migrations of either of 
the pike perches or regarding the breeding habits of the sauger. The pike perches 
and the yellow perch have shown a remarkable decline in commercial importance 
in the Mississippi Basin as a whole during the past 30 years. Other representatives 
of the perch family collected by Stringham in the vicinity of Keokuk were identified 
as follows : 
Hadropterus phoxocephalus (Nelson), darter: A few samples were caught in minnow seines at 
and near Keokuk in both years. 
Cottogaster shumardi (Girard), darter: Several specimens taken at Keokuk were secured during 
1915. 
Boleosoma nigrum (Rafinesque), Jonny darter: Among fish collected near Sandusky, Iowa, in 
Keokuk Lake and its tributaries by Henry McAdams during September, 1915, there was one 
Johnny darter measuring 4 centimeters total length. 
Ammocrypta pellucida (Baird), sand darter: On September 2, 1915, somewhere in the river 
between Keokuk and Hamilton, Luther McAdams collected an example of this species 4.9 centi- 
meters in length. 
Pcecilichthys ( Etheostoma ) cwruleus (Storer), rainbow darter, soldierfish: On July 29, 1915, at 
Cheney Creek, a specimen 4.4 centimeters in length over all was taken bulging with eggs. In Sep- 
tember, 1915, another, 4.8 centimeters long over all, was taken in or near Keokuk Lake, near 
Keokuk. On March 13, 1915, in Cheney Creek, the following specimens were taken: 1 fish 5.4 
centimeters long, with chironomid larvae, mostly Chironomus, and insect d4bris in the stomach; 
1 specimen, 5.3 centimeters in length and highly colored when fresh, containing the same kind of 
food; and 1 specimen, 5.3 centimeters long over all, and also brightly colored, containing chironomid 
larvae, diatoms, and Mougeotia (alga) in the stomach. 
A fish caught by Henry McAdams near Keokuk about June 28, 1916, belongs to this genus. 
It was submitted to Dr. W. C. Kendall, who reported that it was near to E. cragini Gilbert, but 
might be an undescribed species. 
THE SEA BASSES (Serranidse) 
Of the great family of sea basses there are a few representatives in fresh waters, 
including two species in the Mississippi River. The distributions of the two species 
are distinct, the white bass, Roccus chrysops (Rafinesque), occurring northward and 
the yellow or striped bass, Morone interrupta, occurring southward; but their respec- 
tive territories overlap to a considerable degree. Only the former species occurs in 
Lake Pepin; but the lower part of Iowa, at least, is well within the region of over- 
lapping. Speaking of the white bass (the northern species), and with reference to 
the region of Quincy, 111., a little south of Iowa, Garman (1890) wrote: “This fine 
species was more abundant than the striped bass [meaning Morone interrupta] and 
ranged in a greater variety of situations. I saw it caught from the swiftest current 
of the river.” His observations referred to conditions in August, 1888. Regarding 
the yellow bass, he said: “Young were frequent in certain of the sloughs and lakes, 
but were not seen elsewhere.” 
