56 FISHES OF ILLINOIS 



CRISTIVOMER NAMAYCUSH (Walbaum) 



(great lake trout) 



Walbaum, 1792, Artedi Piscium, 68 (Salmo). 



G., VI, 123 (Salmo), J. &G..317 (Salvelinus); M. V., 80 (Salvelinus) ; J. & E., 1,504; 

 N., 44 (Salmo); J., 54; F., 73 (Salvelinus); L., 21. 



Length 3 feet; body elongate, depth 4 in length. General coloration 

 dark grayish green to brownish, sometimes paler, sometimes almost 

 black; everywhere with rounded paler spots, which are often yellowish 

 or reddish tinged ; head usually vermiculate above ; dorsal and caudal 

 reticulate with darker, the anal faintly so. Head 4J long, and its upper 

 surface flattened; eye 44 in head; interorbital space 3i; nose 3|; mouth 

 very large, the maxillary extending much beyond eye, nearly half length 

 of head ; teeth very strong. Dorsal rays 1 1 ; anal 1 i ; caudal well forked. 

 Scales very small, 18S to 210 in longitudinal series; lateral line con- 

 tinuous, pores about 100. 



This magnificent species, one of the three most important fishes 

 of our Great Lakes is, like the whitefish, a species of northern distri- 

 bution. It is found throughout the Great Lake region, and in the 

 lakes of New York, New Hampshire, and Maine, thence to the head- 

 waters of the Columbia and Fraser rivers and the streams of Van- 

 couver Island, and northward to the arctic circle. It is common in 

 the northern part of Lake Michigan, but rarer to the southward. 

 In our Illinois markets it is known almost wholly by the name of 

 lake trout, but farther north the names of Mackinaw trout, salmon- 

 trout, and namaycush are sometimes used. It is extremely vari- 

 able in size, form, and color, particularly under the influence of local 

 conditions, and hence has received many local names. 



Although the usual weight of specimens taken in large -meshed 

 gill-nets is about eight pounds, and of those captured with lines and 

 seines not more than two pounds, the species is said by Goode to 

 attain a weight of a hundred and twenty pounds, which is eight 

 times the maximum size of the closely allied brook trout. "This 

 is due, perhaps," he says, "to the greater ease with which, for hun- 

 dreds of generations, the lake trout have obtained their food. 

 They are almost always found in the same lakes with one or more 

 kinds of whitefish, whose slow helpless movements render them an 

 easy prey, and upon whose tender luscious flesh the lake trout feeds 

 voraciously." This trout is a fish of highly predaceous habit, living 

 especially upon lake herring of all sizes, but eating, in an emergency, 

 almost any animal food which comes in its way. 



A lake trout twenty-three inches long has been known to swallow 

 a burbot of a length of seventeen inches, and whitefish of two or 



