able we must reluctantly predict even poorer whitefish fishing for 1965, the 1965 

 year class apparently having been a poor one. A few years ago, when it was learned 

 the exploitation rate by the fishery was unusually high, restrictions were recom- 

 mended and adopted. It is now apparent that other factors, probably environmental 

 changes as described in the section on Limnology, have a greater influence on the 

 whitefish than does exploitation by the commercial fishermen. 



The lake trout research project, in co-operation with New York State, entered 

 its final stage with the last large planting of 100,000 marked yearlings obtained 

 through the Great Lakes Fishery Commission from Charlevoix, Michigan. The 

 transfer of the fish by air in plastic bags, a technique developed in 1963, was 

 successful, and the planting in the Charity Shoal area of the lake was completed 

 without mishap. The large plantings will be followed carefully to see whether a 

 successful spawning will result in five years, or failing this objective, it is hoped 

 the causes of failure, sea lamprey or otherwise, can be identified with certainty. 



The fishery for eels has been a small but stable industry in Lake Ontario for 

 many years. In recent years, coincident with the declining numbers of other 

 commercial species, it has assumed a greater importance and has been expanded 

 Concern about the effect of the barriers to elver migration presented by installa- 

 tions of the St. Lawrence seaway has led to a small study of this specie^. The 

 objective is to determine the effect, if any, of the seaway on the eel population, 

 and to devise a technique to maintain the supply of elvers from the Atlantic 

 Ocean ii this appears necessary. 



The research vessel "Namaycush", fitted for trawling, carried out our first 

 brief survey of the entire lake in 1964. The results of this, and of co-operative 

 work by other agencies shows that the open lake is not polluted, is rich chemically 

 and in fish food organisms, but contains very few fish. 



The Kokanee programme is covered in detail elsewhere in this report. In 

 Lake Ontario it is now apparent that natural spawning facilities may be limited, 

 but the richness of the open lake waters suggests that growth of the young planted 

 fish might be excellent. 



LAKE ERIE 



The walleye fishery in the western basin of Lake Erie remained at a very low 

 level, comparable to the levels prevailing in the 1930's and early 1940's. The 1962 

 year class, which had been considered as comparable in size to that of 1959, and 

 which was expected to boost the fishery in the spring of 1964, failed to meet 

 expectations. Samples from experimental and commercial gear indicate that the 

 1963 year class is about as numerous as was the 1962 year class, and consequently 

 no improvement in the fishery for 1965 can be predicted. 



In Lake Erie the environment and the fish populations are changing rapidly, 

 and the fishing industry is widely spread. Under these circumstances, it has proven 

 difficult to adequately sample the fish caught so that predictions to the industry 

 of what to expect next year can be provided. Such predictions are important to 

 management and to the industry and longer range predictions are desirable. In 

 the hope of providing such predictions cheaply, research is proceeding on the 

 development of index stations. It is hoped that by fishing certain gears, at selected 

 stations once or twice a year, a reliable measure of the relative abundance of young 

 important species can be achieved. This, in time, should allow long range predic- 

 tions of fishing conditions, provided that year class strengths are established at 

 an early age, as we believe them to be. 



Studies of the factors, e.g. temperature and oxygen, etc., influencing the 



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