104 



Fat-headed minnow 



soft swollen pad on top of neck region; breeding 

 tubercles on snout and under chin; lining of body 

 cavity black; intestine two to three times body length. 

 This fish is generally distributed throughout 

 southern Canada and northern United States. In Michigan 

 and northern Wisconsin it frequents boggy lakes, ponds, 

 and streams. In southern Wisconsin and in southern and 

 western Minnesota, it is found commonly in small ponds 

 and silty streams. 



.The males are larger than the females and reach a 

 maximum length of 3i inches. They bear pearl organs 

 on their black heads and soft, swollen pads on their 

 backs during the spawning season. The spawning season 

 extends in some localities from May until the latter 

 part of August. A temperature of about 64° F. seems 

 necessary before spawning begins. The females may 

 reach maturity and begin spawning the following spring 

 at an age of 1 year. The eggs are deposited on the 

 underside of many objects in a pond. Several females 

 may deposit their eggs in a nesting site .which is 

 zealously guarded by one male. Prom 36 to 12,000 eggs 

 have been deposited at one site in a circular or oval 

 spot. A single female has yielded 4,144 offspring in 

 11 weeks, and spawned 12 times. The eggs hatch in 45 

 to 6 days. The older fish in a pond should be used 

 for bait when they have spawned, as they die soon after. 

 This minnow is a popular bait for panfish in 

 Minnesota. It has been used for pike fishing when 

 larger species are not available. After the early 



