130 NORTHERN FISHES 



taken from the natural spawning beds of the walleyes, and most of them 

 had empty stomachs, though they had abundant opportunity to feed 

 on the spawn. However, if they are feeding suckers will probably eat 

 even their own eggs. Normally, aquatic plants form an important part 

 of their diet, which is varied with insect larvae, mollusks, worms, and 

 other small animals. 



The young of this species and the next one, C. catostomiis catostomus, 

 arc among the very important, if not actually the most important, forage 

 fishes native to our waters. From the time they emerge from the egg 

 until they reach a length of 8 inches, suckers are the natural food of the 

 pikcperch, or walleye, and northern pike. 



Suckers are the most easily handled of all our fishes under the usual 

 methods of artificial production. They hatch about 95 per cent under 

 normal conditions and in ordinary ponds grow to a length of 4 inches or 

 more the first summer. It is predicted that they will eventually become 

 one of the most important bait "minnows" if, as appears certain, it 

 becomes necessary as a conservation measure to forbid the taking of 

 minnows from public waters for sale as bait. 



NORTHERN STURGEON SUCKER (Longnose Sucker, 

 Red Sucker) 



Catostomus catostomus catostomus (Forster) 



This species can usually be distinguished from the preceding one, 

 C. coimnersonnii cormnersonnii, by its long, pointed snout, which ex- 

 tends considerably beyond the mouth, and by its very small scales, much 

 reduced and crowded anteriorly, and numbering more than 95 (95- 

 114) in the lateral line. It is variable in coloration. The spring males are 

 profusely tuberculate on head and anal fin and have a broad, rosy 

 lateral band, which persists until late in the summer. This species reaches 

 a length of over 2 feet. 



The northern sturgeon sucker ranges from the St. Lawrence and 

 Great Lakes basin westward into the Rocky Mountains and also north- 

 ward. In Minnesota they are abundant in Lake Superior, Lake of the 

 Woods, Rainy River and its tributaries, and Vermihon Lake. They 

 have been taken in the St. Louis River at Fond du Lac, near Duluth, 

 and also from Lake Saganaga and Kimball and Mink lakes in Cook 

 County. In general they are distributed throughout the Arctic and 

 Superior drainages and are inferior in numbers to the common sucker. 

 They usually occur in large numbers wherever found in the northern 

 part of Minnesota, but they have never been seen in the Mississippi 

 drainage. Greene (1935) reported them from the drainages of Lake 

 Michigan and Lake Superior in Wisconsin. In the deep northern lakes 

 they often range to great depths. In Lake Superior they are taken 

 occasionally at depths of 600 feet, but the commercial fishermen who 

 fish at these depths claim that they seldom go this deep. 



