104 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



man, they might again reach the enormous weight of early citations, 

 their shiggish movements and voracity being conducive to such a result. 



The nature of their environments has a decided influence on the 

 characteristics of this spe ies; the temperature of the water, food, and 

 character of bottom entirely changing the marking and peculiarities of 

 these fish in their various habitats. 



Until recently it was commonly thought that the principal food of the 

 lake trout was the young whitefish, and for this reason the fishermen 

 of the lakes were generally unfavorable to its artificial propagation. 

 The error of that belief, however, is now generally conceded, though 

 no doubt quite a number of young whitefish become food for trout 

 during each season. But as the habits of the lake trout take it to 

 deep water immediately after spawning, while the young whitefish 

 remain in shallows, the few which are destroyed in this manner are 

 either stragglers from shoal to deep water or taken by trout aimlessly 

 wandering from their natural range. The lake trout is an omnivorous 

 feeder and has a ravenous appetite. It greedily devours all fishes 

 X)ossessing fins of flexible character, and jackknives, corncobs, and 

 other articles equally indigestible have been found in its stomach. 



The spawn and fry of lake trout suffer from the same enemies as the 

 young of all fishes, but the mature fish are too formidable for other 

 species to prey upon. They are troubled with a few parasites. Oc- 

 casionally individuals, very thin in flesh and sickly-looking, known as 

 "racers" by fishermen, are found swimming near the surface; no 

 sufficient cause has been discovered for this condition, as they are no 

 more afflicted with parasites than healthy fish. 



IMPORTANCE AND ABUNDANCE. 



The trout fisheries of the Great Lakes are second in importance 

 commercially, the whitefish ranking first. At one time trout were so 

 plentiful that they did not command a price at all proportionate to their 

 edible qualities, but as the fishing continued the catches decreased, 

 until about the year 1886 the market price of trout became equal to 

 that of its more delicate rival. At this time it became evident to the 

 Federal and State governments, as well as to those dependent upon 

 this industry for a livelihood, that decisive steps ought to be taken 

 toward providing against the extermination of this valuable food-fish. 

 Artificial hatching was commenced that year with the object of restock- 

 ing the Great Lakes. The work progressed only in a limited way up 

 to 1892, when the output of both the United States and Michigan Fish 

 Commissions reached something like its present proportions. During 

 the season of 1895 the United States Fish Commission station at 

 Northville secured over 11,000,000 lake-trout eggs. As indicative of 

 the success attending the plants of lake trout, it may be remarked that 

 for a short period during the season of 1896 the fishing-boats, which 

 had been working to their fullest capacity, ceased operations, the 

 market being glutted and the remuneration not being commensurate 

 with the labor, hardship, and capital invested. 



