The Common Whitefish 



places are also said to serve the same purpose, but this fact has 

 not been entirely substantiated. The distribution of the grounds 

 on the platform is from the neighborhood of Kelleys Island to 

 near the Michigan shore, on both sides of the boundary line. 

 Some of the best known are two shoals north of Kelleys Island; 

 the reefs and rocky shores about and in the neighborhood of 

 North Bass, Midde Bass, Rattlesnake and Green islands; the reefs 

 about the Hen and Chickens, Niagara Reef, and occasional patches 

 off the mainland shores. The depth ranges mostly from about 

 4 to 20 feet, but is sometimes greater. It is in these places that the 

 gillnet fishing is carried on during the spawning time, and mainly 

 here and in the Detroit River that the eggs have been obtained 

 for the artificial propagation of the species, The fish taken in 

 the Detroit River are mostly bound for Lake St. Glair, although 

 the river itself is said to contain one or more spawning places. 



It seems scarcely credible that the great stock of whitefish 

 which has characterized the deeper waters, where the catch has 

 many times exceeded that of all the remainder of the lake com- 

 bined, can have been maintained solely through the agency of 

 that body of fish which reaches the western platform, and it is 

 possible that extensive spawning areas will sometime be dis- 

 covered farther east. One small ground is known to be located 

 between Dunkirk and Westfield, N. Y., and two others are reported 

 off Port Dover and Port Burwell, Ontario. 



The spawning time varies somewhat in different years, de- 

 pendent on the conditions of the weather and also with respect 

 to the locality. Our information on this subject is mainly limited 

 to the platform, where the dates have been accurately determined 

 in connection with fishcultural operations, as follows: Ripe eggs 

 have been obtained, but only rarely, as early as the latter part 

 of October, the first being taken generally in the early part of 

 November. Spawning may continue into the first week of 

 December, but the last eggs are seldom secured later than Decem- 

 ber i, generally a few days before that date. The bulk of the 

 eggs have usually been obtained between the loth and 25th of 

 November, but sometimes beginning as early as the 5th or 6th 

 and continuing as late as the 28th, which dates may be consid- 

 ered to mark the limitations of the main part of the spawning 

 season. These figures are based on the averages for several 

 years and for the different grounds where eggs are procured for 



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