532 



BULLETIN OF THE BUREAU OF FISHERIES 



(See Table 89.) The whitefish are found inshore as soon as or shortly after the nets 

 are set and are at their best in June and July — earlier in those nets to the south or in 

 shallow bays (Whitefish Point, Marquette, Black Bay and Nipigon Bay), and 

 later in other places (Gargantua and Batchawanna). In the shallowest nets the fish 

 are practically absent after the middle of July, and after early August they are taken 

 only in the deepest nets. At Whitefish Point some are said to have been caught in the 

 90-foot nets throughout the summer. The runs return in the fall (if the nets are not 

 blown out before), from mid-September to late October, depending on the locality. 



Data from the gill nets. — Gill nets are set for whitefish in most of the areas where 

 they are caught in pounds. As soon as the ice breaks the whitefish are found along 

 the banks in from 20 to 35 fathoms. When the water temperature rises in June and 

 July the nets are moved shallower. When the water is warmest (in August) the fish 

 leave the shoals, and then the catches, as a rule, decrease. The inshore run in the fall 

 is again a favorable time for the gill netters, though often the weather is too inclement 

 to risk the netting in the shallow water. 



John MacMillan, of Sault Ste. Marie, Ontario, informs me that in the summer 

 whitefish can be taken in commercial quantities in the 60 to 70 fathom holes off 

 the Lizard Islands. Other fishermen have found stray individuals in water as deep 

 outside the main banks, and originally when the species was more abundant captures 

 at that depth along the shores were still more common, probably due to the over- 

 crowding of the more favorable shoal areas. 



Thus, all the data we possess on the movements of the whitefish indicate that for 

 the most part they are to be found in early spring at depths of 20 to 35 fathoms, 

 probably in those localities where shallower water is too disturbed by currents to 

 offer suitable conditions. As the season advances they move onto the shoals, leaving 

 these again when the waters become warmest, and then occurring rather sparingly 

 anywhere until the schools come ashore again in the fall to spawn. While they prefer 

 relatively shallow water at all times, as in other lakes, there is evidence that at times 

 they occur at 60 or 70 fathoms, where such depths are near shallow areas. 



The fingerlings probably live along the beaches during most of the year (Hank- 

 inson, 1914). 



BREEDING HABITS 



The average time of spawning for the species is during the month of November, 

 though here, as elsewhere, the spawning season is not uniform for every locality on 

 the lake. It appears that, as a rule, the northshore whitefish spawn earlier than those 

 in other sectors. If it is a question of lowered temperature that induces spawning, 

 the phenomenon probably can be explained, inasmuch as the bays, which are shal- 

 lower and more northerly, probably cool more rapidly than the main lake. 



No extensive spawning grounds are known, but areas suitable for spawning are 

 scattered along most of the shore stretch where whitefish are found in the summer. 

 The bottom selected is sand, gravel, or small stones at depths from 1 to 12 fathoms. 



Nothing is known of the breeding behavior of the species in Lake Superior. 



The size of the whitefish at maturity varies with the locality, as in the other lakes. 

 The whitefish from Rossport and in Black Bay are notably small, according to the 

 fishermen, not often exceeding 4 pounds in weight. I have collected specimens with 

 maturing gonads less than 300 millimeters iD length from these localities, though 



