52 FISHES OF ILLINOIS 



This is a northern species, occurring in vast abundance in all the 

 Great Lakes and in some of their tributary waters, and ranging north 

 to the Arctic Ocean. It was formerly abundant in southwestern 

 Lake Michigan within the limits of the State of Illinois, but is now 

 taken from that part of the lake, if at all, in very small numbers 

 only. It is still much the most important food species occurring 

 within our territory, but reckless fishing has reduced it to insignif- 

 icance as an Illinois fish. The longshore fishery in this state, 

 which as late as 1885 produced over eighty thousand pounds per 

 annum, yielded only some two hundred pounds in 1899. Indeed, 

 the total catch of the several species of whitefish {Coregonus) in the 

 Great Lakes, now gives us only five million to eight million pounds 

 a year as compared with eighteen million pounds in 1885 and 

 twenty-one million pounds in 1879. 



The record 'weight of a single whitefish is twenty-three pounds 

 — the weight of a specimen taken at White Fish Point, Lake Supe- 

 rior. Its mean weight in northern Lake Michigan is four or five 

 pounds, and fishes weighing as much as fifteen pounds are now very 

 rare. 



This is probably, on the whole, the favorite food-fish of our in- 

 land waters. In the words of Sir John Richardson, "Though it is a 

 fat fish, instead of producing satiety it becomes more agreeable to 

 the palate, and I know from experience that, though deprived of 

 bread and vegetables, one may live wholly upon this fish for months, 

 or even years, without tiring." It is mainly eaten fresh, but it is 

 also smoked or salted in considerable quantities. 



This species spends most of its time, as a rule, in the deeper and 

 cooler parts of the lakes which it inhabits, coming towards the shore 

 and sometimes entering streams in October and November as the 

 spawning season approaches. In many lakes there is a migration 

 movement from deep to shallow water in early summer also. The 

 whitefish spawns during October, November, and December, in 

 depths varying from eight to fifteen fathoms, beginning, it is said, 

 when the water reaches about 40° F. It is most active on its spawn- 

 ing grounds in the evening and at night, each female depositing 

 several hundred eggs at a time, and the total number' averaging 

 about ten thousand for each pound of her weight. 



The young usually appear in March and April, swimming sep- 

 arately near the surface, and soon seeking deep water to feed and to 

 escape their enemies. Their first food consists mainly of the smaller 

 Entomostraca of the plankton, the capture of which is facilitated by 

 the presence, on the lower jaw of the young fish, of four sharp 



