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species. A “spring run” of paddlefish is sometimes spoken of, but this expression is 
used so generally and loosely that no particular significance can be attached to it as 
bearing upon a migration of the character in question. Stockard (1907, p. 761) 
furnishes observations of a conspicuous lateral migration from rivers to lakes and from 
lakes to rivers. This statement may be quoted: 
During the spring, when the water of the Mississippi River rises for several feet and backs into 
the bayous, thus establishing connections with the large lakes, Polyodon begins immediately to come 
into the lakes from the river and continues to come in large numbers so long as a sufficient connec- 
tion is maintained. To do this it must often make long journeys through rather shallow water, in 
which many obstructions, such as bushes and trees, are frequently met. Thus, it finally reaches the 
lakes in a rather emaciated condition and with its body scarred and scratched. * * *. It is 
equally true that the fish in the river-lakes (those lakes more directly connected with the river) 
migrate out into the river when the water begins to back in during the spring, so that fishermen 
often abandon their fishing in these places at such a season, since most of the desirable Polyodon 
have made their escape. 
Wagner (1908, p. 27) says: “Seemingly the spoonbill is of a rather roving dis- 
position, cruising up and down the lakes in large schools.” He observed that it might 
be taken abundantly in the seine one day, while the next day there might be none. 
At various places along the river commercial fishermen speak of “shoals” of paddle- 
fish, suggesting a gregarious habit. 
The peculiar feeding habit of the paddlefish doubtless makes necessary a relatively 
active life with extensive local migrations in search of food. The paddlefish, unlike 
other fish of like size, does not take large animals as food but subsists upon the minute 
plant and animal life, which it obtains by straining enormous quantities of water. 
It must be in constant movement when feeding, and its daily local distribution must 
be affected by conditions affecting the abundance of plankton food supply. 
Dr. R. A. Muttkowski determined the stomach contents of five paddlefish 
taken by Stringham at various dates from April to August and found the material 
to consist chiefly of insect larvae (burrowing May-fly nymphs, other May-fly nymphs, 
caddisfly larvae, and odonate larvae) and insect remains, with small quantities of 
plant and other debris, pieces of wood, and some parasitic nematodes. The 
stomach contents of a paddlefish submitted to the Bureau of Fisheries from Louisiana 
and examined by the author contained almost exclusively the pelagic and translucent 
Corethra larvae. Such observations indicate that the paddlefish may feed either at 
the bottom or in the water above, a matter about which there has been difference of 
opinion. 
There is one other matter for remark in reference to the paddlefish at Keokuk. 
The author has not infrequently observed paddlefish taken below the dam having 
the snout broken squarely off, the wound being fresh. We have not been able to 
discover the cause of this injury. Experiments elsewhere described (Coker, 1929, 
p. 1 1 1) show that the fish can be passed over the spillways or down through the turbine 
without experiencing such injury, but unquestionably there is some condition about 
the dam that permits of the paddlefish incurring the loss of its snout. It is con- 
ceivable that such an accident could occur to a paddlefish attempting unwittingly 
to pass between the submerged piles of old cofferdams and other construction work 
in the exceedingly swift waters of a tailrace. This fish, as is well known, has very 
deficient sight (Hussakof, 1911, p. 246), and in finding its way it apparently depends 
chiefly upon the delicate tactile sense organs in its snout. In cases of this kind the 
sensory warning might well come too late to save the snout. It has been suggested 
