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River chub 



Nocomis micropogon (Cope) 



General de script ion. — Body robust, nose blunt, 

 scales large and easily seen, similar to horny-headed 

 chub (preceding); black spot at base of tail indistinct 

 and of no definite shape; tail fin of young soTnetimes 

 amber but not red; no red spot behind eye; several 

 large tubercles on swollen forehead of breeding males. 



The river chub, Nocomis micropogon (Cope), is found 

 in southern Michigan and is used as a bait minnow there, 

 but it is not found in Wisconsin or Minnesota, It 

 differs from the horny-headed chub in having an indis- 

 tinct black spot of no definite shape at the base of the 

 tail, no red on the caudal fin, and in its preference 

 for larger rivers. 



Its life history is similar to that of the horny- 

 headed chub. The river chub also frequents large rivers 

 from Michigan southward to Virginia and Alabama. 



Excellent descriptions of breeding habits have 

 been written by Michigan investigators. According to 

 their observations, the male first digs a pit 12 to 15 

 inches in diameter and 3 to 6 inches deep in the stream 

 bed in water less than 2 feet deep. Stones are removed 

 by being carried away in the mouth. The male then fills 

 the pit again with other stones until a heap of large 

 pebbles, 30 inches across and 3 inches high, is accumu- 

 lated; all in 2 to 5 days. Small "spawning troughs" are 

 than made by the male in the surface of this stone pile 

 to receive eggs and milt as they drop from the spawning 

 fish above. The troughs are filled again with pebbles 

 immediately after spawning. Common shiners, horny- 

 headed chubs, and stone-roller minnows may use the 

 stone pile for a spawning place at the same time. 



