hatching. It seems important, therefore, to pursue these studies to learn where 

 these young fish are, how they live, and what factors in their environment work 

 to reduce their numbers. 



Further studies on the growth, distribution and survival of partially selected 

 splake hybrids were made in South Bay and in northern Lake Huron as part of 

 the preparation for the rehabilitation programme using this new fish. 



The second planting of kokanee was made in Lake Huron and the scientists 

 were occupied with developing new fishing techniques to allow early assessment 

 of the success of these plantings. A section appearing later reports more fully on 

 this project. 



LAKE SUPERIOR 



The research programme on Lake Superior, under the terms of the present 

 Federal-Provincial agreement, is a Federal responsibility. Preliminary negotiations 

 to develop a new agreement to meet changing conditions proceeded during 1965. 

 It is expected that the Fisheries Section will resume responsibility for the Lake 

 Superior programme under the revised agreement. 



In the sea lamprey control experiment, the second cycle of stream treatments 

 was completed on Lake Superior and it is expected that the programme will be- 

 come a management responsibility as control is initiated on Lake Huron in 1966. 

 Assessment of the effectiveness of control and of the lake trout planting programme 

 in rehabilitating Lake Superior will continue for a number of years. During 1965 

 there was further evidence that both native and planted stocks of lake trout were 

 continuing to improve. A limited commercial fishery was again allowed on the 

 off-shore populations. 



KOKANEE 



In 1964, the Research Branch, after study of available information, recom- 

 mended an experiment to introduce kokanee, a land-locked variety of sockeye 

 salmon to the Great Lakes. Lakes Huron and Ontario were chosen as sites for 

 the experiment because they appeared suitable in most respects environmentally, 

 and because of the depressed state of their commercial and sport fisheries. Four 

 annual plantings of kokanee were planned, and the first of these, involving a total 

 of three million eggs, was made in the winter of 1964-65 and during the spring 

 of 1965. Assessment work during the summer and fall produced encouraging 

 results, particularly in South Bay, Lake Huron, where the highest concentration 

 of eggs was planted. Good growth and survival were recorded. The second 

 planting, again of three million eggs, was made in the winter of 1965 and the 

 spring of 1966, and preparations were made for an intensified assessment pro- 

 gramme. Preliminary investigations were undertaken of the possible arrange- 

 ments for an increased supply of eggs, with a view to increasing stocking density. 



The results of this work to date have been so encouraging that the formation 

 of a separate research unit has been recommended for the additional effort required 

 to assure success. 



SPLAKE 



The selective breeding research programme has been concentrating its efforts 

 since 1957 on the development of a hybrid selected in such a way as to fit the 

 environment formerly occupied by the lake trout in the Great Lakes and selected 

 also to enable it to reproduce in spite of the presence of some sea lampreys. 



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