In the fall of 1965 the first small number of splake, adequately selected in 

 these respects were produced at the Southern Research Station, Maple. Additional 

 numbers and year classes are in culture and will come through the selection pro- 

 cedures during 1966 and subsequent years, provided that adequate physical facili- 

 ties are made available. Agreement was reached with U.S. agencies to undertake 

 the rehabilitation programme in Lake Huron using the highly developed splake 

 rather than lake trout. This agreement provides the opportunity to undertake the 

 final test of splake. They will be planted on a large scale and we shall then learn 

 whether or not they indeed do behave as we have planned, and whether or not 

 they will reproduce successfully. All signs point to success in this bold experi- 

 ment, and if it is achieved it will prove a major advantage economically to the 

 Department and to the fishermen. 



Plans were made to share our present stock of highly selected splake with 

 U.S. agencies. These fish are the first installment of brood stock to be reared in 

 management hatcheries to maturity for the production of large numbers (2-3 

 million annually) for planting in Lake Huron. Large scale plantings should be 

 possible in 1969 or 1970, at which time we expect sea lamprey control to be 

 effective in Lake Huron. 



Game Fish Programmes 



HARKNESS LABORATORY 



The Harkness Laboratory in Algonquin Park was operated again in 1965 in 

 accordance with the terms of the agreement between the Department of Lands 

 and Forests and the University of Toronto. The Fisheries Section makes much 

 greater use of the facilities than the University. During 1965 they were used by 

 scientists from our Brook Trout, Lake Trout, Limnology, Parasitology, Selective 

 Breeding and Productivity research units. Staff and graduate students from the 

 University of Toronto and staff of the Ontario Research Foundation also based 

 field studies at the Laboratory. 



A history of the Laboratory covering staff and projects since its establishment 

 in the 1930 decade was completed during 1965 and should be published soon. 



LAKE TROUT 



Lake trout studies gave emphasis to the analysis of accumulated data in order 

 that future field projects be properly oriented. One analysis completed a project 

 dealing with the differences in lake trout populations associated with differences 

 in feeding habits. The lake trout which feed on plankton during the summer 

 months were found to be different in many respects from those which feed on 

 fish throughout the year. Some of these differences require quite different manage- 

 ment techniques. 



BROOK TROUT 



Brook trout research continued to emphasize stocking rate studies. Some 

 fifteen lakes, representing a cross section of brook trout waters, are involved in this 

 project. The first experimental plantings, at different densities were made in 1962, 

 assessment of growth and survival being completed in 1963 and 1964. Replicate 

 experimental plantings made in 1964 were assessed in 1965. In general it is 

 apparent that a much greater return to the angler is realized from plantings of 



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