354 



BULLETIN OF THE BUREAU OF FISHERIES 



waukee, Wis., in 22 to 25 fathoms; on November 8, 1920, 18 miles NNW. of 

 Michigan City, Ind., in 30 to 38 fathoms; on November 19, 1920, 17 miles NNW. in 

 28 to 32 fathoms; on August 10, 1923, 8 miles NNW. of Big Rock Point, Mich., in 

 45 to 50 fathoms, and on August 21, 1923, off Charlevoix at probably the same 

 depth. 



Besides the 2^ and 2 ^4 inch nets that are fished for Leucichthys, there are 

 other sources of data on the occurrence of Leucichthys, which however, have yielded 

 nothing bearing on johannx — the 4 to 4^ inch whitefish and trout nets and the 

 lj^-inch bait nets, both usually set at depths less than 40 fathoms. In the 4 to 

 43^2 inch nets no chubs could gill, as no specimen of this species has been known to 

 grow so large; but no individuals ever have been seen by me to have been entangled 

 in its meshes. Fish caught thus are only accidental inclusions, however, and even 

 small fish might actually be present in numbers and yet not be caught, so that the 

 want of data from this source is not conclusive. 



In the 13^-inch nets small individuals could gill along with the small hoyi and 

 other Leucichthys, but. no specimens of this species were seen in lifts of these nets 

 made from 26 to 40 fathoms on June 23, 1920, off Northport, Mich.; on July 18, 

 1923, in West Grand Traverse Bay; on August 27, 1920, 4 miles west of Manistee, 

 Mich.; on September 25, 1920, 5 miles E. Y S. of Port Washington, Wis.; on Sep- 

 tember 28, 1920, 5 miles SE. by E. of Sheboygan, Wis.; on October 8, 1920, off 

 Racine, Wis.; and on March 2, 1921, 14 miles NNW. of Michigan City, Ind. 



No specimens occurred either in the special 13^-inch nets lifted from 4 to 16 

 fathoms on July 25, 1923, off Traverse City, Mich., from 8 to 12 fathoms on July 

 21, 1923, and from 15 to 25 fathoms on July 23, 1923, in Platte Bay, and from 8 to 

 10 fathoms on July 30, 1923, off South Manitou Island, Mich. 



All the data thus show that at certain seasons, at least, the chub does not occur 

 at depths of less than 30 fathoms and that it ranges to depths of 90 fathoms. It is 

 likely that it goes even deeper. The small individuals, it appears, either do not 

 consort with the small hoyi or else may not be found outside the 40-fathom contours. 



RELATIVE ABUNDANCE 



Throughout the summer and fall of 1920 small lifts were made from the chub 

 nets at every port on the lake. Lifts examined during the season, including the 

 lifts made out of Milwaukee and Michigan City on the spawning grounds of 

 zenithicus, ranged between 20 and 180 pounds of fish to the mile of net when lifted 

 after five nights. As never more than three fish are required to make a pound, it 

 is obvious that fish were uncommon along the bottom. Lifts in which no fish of 

 this species were taken are enumerated in the preceding section. Lifts in which 

 only an occasional chub was taken were made as follows: On June 22, 1920, and 

 on July 31, 1923, 5 miles northwest of Cathead Light, Mich., in 40 to 60 fathoms; 

 on June 29, 1920, 5 miles N. by E. and on August 11, 1923, 3 miles NW. Y W. of 

 Charlevoix, Mich., in 35 to 65 fathoms; on August 12, 1920, 15 miles SE. by S. Y 2 S. 

 of Manistique, Mich., in 60 to 70 fathoms; on August 24, 1920, 10 miles E. by N. 

 of Algoma, Wis., in 35 to 50 fathoms; on September 23, 1920, 27 miles ESE. of 

 Milwaukee, Wis., in 60 fathoms; on September 25, 1920, 18 miles E. Y 2 S. of Port 



