12 THE REPORT UPON GAME AND FISHERIES FOR 1928 No. 9 



The effect of three-inch mesh gill net on lake trout in Lake Huron and 

 Georgian Bay was made the subject of preliminary study by Mr. G. W. 

 McCracken. 



Messrs. H. H. MacKay and R. A. McKenzie studied the effects of trade 

 wastes on fish life in Puce's Creek (Essex County), Sydenham River (Lambton 

 County), Thames River, Sturgeon River (Nipissing), and the Winnipeg River. 



Specific complaints in regard to obstruction to fish migration in the Humber 

 River at Lambton Mills and the Nonquon River, near Port Perry, were investi- 

 gated. The latter investigation is not completed. 



Mr. H. H. MacKay studied a parasitic infection of speckled trout from 

 MacKay 's Lake, Algoma, and mortality among goldfish at the Goldfish Supply 

 Company, Toronto. The exact identity of flat-worms parasitic on pickerel 

 sent to the Department from Clearwater Lake, Kenora, and fluke-worms para- 

 sitic on speckled trout sent to the Department from Norwood, Ontario, were 

 determined by Mr. George W. Hunter, of the Rensslaer Polytechnic Institute, 

 Troy, New York. In collaboration with Dr. Read, Professor of Bacteriology, 

 Queen's University, Kingston, Messrs. R. A. McKenzie and G. W. McCracken, 

 studied an epidemic disease among suckers in Long Lake, Portland Township, 

 Frontenac County. 



Mr. A. VV. McLeod, Director of Hatcheries, and Mr. H. H. MacKay, 

 Biologist, and his field assistants, investigated twelve sites suggested for the 

 propagation of bass, or for bass and maskinonge, and seven sites for the propa- 

 gation of speckled trout. 



Noteworthy progress has been made in the culture of speckled trout. In 

 Table III, following, the number, age and size of speckled trout dis- 

 tributed are given. There is considerable variation in the size of fish taken 

 from different hatcheries. Available rearing ponds at Normandale and Mount 

 Pleasant place the fish of these hatcheries at a decided advantage, over those 

 retained in hatchery troughs and fed exclusively on artificial food until they 

 are distributed. Stream and pond conditions at Mount Pleasant and Norman- 

 dale are as natural as might be expected, and the fish reared under these condi- 

 tions have considerable natural food at their disposal. Small-mouthed black 

 bass distribution is outKned in Table I\'. In Mount Pleasant hatchery ponds 

 during the past year production of fry amounted to approximately 100,000, or 

 a production of 6,250 per fertile nest. Half the fry were distributed as fry, 

 and of those retained, a distribution of 10,833 fingerlings of the sizes and ages 

 shown in Table I\' resulted. 



