GREAT LAKES COREGONIDS 



469 



Minn., in 30 to 40 fathoms (record 9); in Thunder Bay on September 15, 1923, 

 inside Thunder Cape in 31 fathoms; on September 17, 1923, inside the Welcome 

 Islands in 23 fathoms; on September 19, 1923, off Sawyer Bay in 49 fathoms; and 

 on September 29, 1923, off Salter Island in 42 fathoms (records 3, 4, 12, 13, 14, and 

 16). Only one specimen was found in the 2% and 2% inch nets lifted on July 11, 

 1922, between Cat and South Twin Island in 15 to 20 fathoms (record 5), and two 

 were taken on October 4, 1921, off Bread Rock in 80 to 90 fathoms (record 15). 

 None occurred in the lifts of gangs of 3 to 10 miles of 4^-inch nets lifted on October 

 3, 1917, off Grand Marais, Mich., in 65 fathoms and deeper; on August 5 and 11, 



1921, 31 miles N. % E. and 18 miles NE. by N. of Marquette, Mich., in 80 to 100 

 fathoms; on June 26, 1922, off Alona Bay, Ontario, in 60 fathoms, and on June 19, 



1922, 6 miles northeast of the east end light of Michipicoten Island in 15 to 35 fathoms. 

 Small stretches of the special 2}/2 to 2% inch nets lifted on several occasions from 11 

 to 80 fathoms had no fish of this species. The lifts of large-meshed nets, in which 

 small fish become entangled, of course, can offer no conclusive data on their abundance 

 in the vicinity of such nets, as it is not known under what conditions these fish become 

 entangled in the netting. It is interesting in this connection, however, to point out 

 that in the gangs mentioned above, lifted off Grand Marais, Mich., on October 

 3, 1917, off Marquette, Mich., on August 5 and 11, 1921, and off Alona Bay, Ontario, 

 June 26, 1922, small Tciyi and zenithicus were ensnarled; and it is at least probable 

 that hoyi, had they been present, would have been taken in the same manner. In 

 the 13^-inch bait nets lifted on June 14, 1922, in Whitefish Bay from 40 to 50 fathoms 

 (record 1) and on August 8, 1921, 6 miles NE. % N. of Marquette, Mich., from 42 

 to 65 fathoms (record 2), the species was fairly common. The hook fishermen, how- 

 ever, are not able continually to find enough bait for their hooks at those depths, but 

 often are forced to set them nearer shore, where they probably take other species 

 of fish. 



Concerning the proportion of other fish that occur in the bait nets nothing is 

 known. It is very likely, however, that small zenithicus are taken regularly among 

 the bloaters at depths of 40 to 50 fathoms. Kiyi probably does not come so shallow 

 often and artedi seldom so deep. 



The data thus indicate that the bloater occurs most abundantfy along the banks 

 that border the deep-water plains. Specimens have been taken as shallow as 15 and 

 as deep as 80 or 90 fathoms, but they are commonest, so far as is known, between 

 he depths of 35 and 50 fathoms. 



BREEDING HABITS 



Nothing is known about the breeding habits of the species except that the 

 specimens taken up to October 4, 1921, showed no mature ovaries. Occasional 

 females that had ova rather larger than those of their companions have been taken 

 during the summer at several ports, and it might be expected that these individuals 

 would spawn earlier than the rest. It is not certain, however, that the ova would 

 ripen prematurely even though their growth was precocious originally. Fishing 

 operations usually are suspended from early December until spring, so that unless 

 the fish spawn before December (which they probably do not) the time and place 

 of their spawning will not be determinable readily. 



