SUCKER 



LIFE HISTORY 



Description. — Sucking m o u t h 

 with thick fleshy lips on underside 

 of head; fine scales near head and 

 coarse ones on tail ; small specimens 

 have three large dark blotches on 

 each side of body ; more than 10 rays 

 in dorsal fin (true minnows have 

 less than 10) ; no spiny rays in any 

 of the fins. 



Range. — This fish is widely dis- 

 tributed in the United States, oc- 

 curring east of the Great Plains 

 from northern Canada, Hudson 

 Bay drainage, to Labrador, and 

 south to Georgia, Arkansas, and 

 Oklahoma. It thrives under a va- 

 riety of conditions, but prefers 

 clear-water lakes and streams. 



Breeding habits. — The sucker 

 runs upstream to spawn early in the 

 spring. It prefers swift water and 

 gravel bottoms, scattering its eggs 

 freely in the current. It will spawn 

 to some extent in lakes if there are 

 no outlets and inlets. Work done 

 in New York indicates that temper- 

 atures from 57° to 68° F. are best for 

 hatching eggs. In this temperature 

 range, the incubation period was 5 

 to 7 days. At 70° F., mortality was 

 high and the incubation period was 

 about 4 days. At 40° F., none 

 hatched in more than 14 days. As 

 many as 47,800 eggs were taken 

 from one female. 



Food. — The sucker has diversified 

 feeding habits. It seems to feed on 

 any food that may appear in the 

 water. A study of 1,080 suckers 

 from Minnesota natural ponds 

 shows the average food content to 

 be cladocera, 30.6 percent; cope- 



pods, 17 percent ; ostracods, 2.4 per- 

 cent; chironomid larvae, 26.4 per- 

 cent; miscellaneous insects, 1.5 per- 

 cent; rotifers, 10 percent; protozo- 

 ans, 0.8 percent ; nematodes, 0.6 per- 

 cent; and miscellaneous organisms, 

 10.7 percent. This list suggests 

 that the planktonic crustaceans are 

 the preferred food of the sucker, but 

 a closer study reveals that chirono- 

 mid larvae are eaten whenever they 

 are available irrespective of crusta- 

 cean abundance. Very small suck- 

 ers prefer small organisms but can 

 exist on larger forms when neces- 

 sary. 



Importance. — The common, or 

 white, sucker is a popular minnow 

 for propagation because it is easy to 

 raise in large numbers, grows rap- 

 idly, is very hardy in the minnow 

 pail, and is preferred by fishermen 

 as a bait for walleyed pike. Suckers 

 are raised more cheaply in natural 

 ponds than in artificial because the 

 sucker needs a large amount of 

 growing space that can be provided 

 more cheaply in natural ponds. 



PRODUCTION 



The white sucker is naturally a 

 fish of clear waters, so ponds ^ for 



1 Many Minnesot.a dealers have had no re- 

 turns from Slicker fry planted in natural 

 ponds. There are four pobable reasons for 

 this : 1. There may not have been ample food 

 for the fry at the time of planting. A question- 

 able pond should be fertilized with barnyard 

 manure about 2 weeks before the fry are 

 planted. 2. There may have been a large pop- 

 ulation of aquatic insects in the pond at plant- 

 ing time. The back-swimmer and the water 

 tiger prey heavily on fish fry and should be 

 killed off 2 days before the fish are planted In 

 the pond (p. 62). 3. The natural pond may 

 have had a population of predatory fish or 

 minnows at planting time. 4. The ponds may 

 not have been stocked with free-swimming fry. 



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