in the early 1950's, which greatly increased the total harvest of this species from 

 the lake, may have had some significance in the recent decline in abundance. 



LAKE ONTARIO 



The dangers for the whitefish fishery inherent in the trend towards increasing 

 variability in year class strength which was illustrated in the recruitment study 

 (in press) this year, were emphasized by evidence of poor recruitment into the 

 fishery during this year. The relative absence of small fish in the summer com- 

 mercial catch has until now proven a reliable indicator of low age 3 representation 

 in the catch, and unless a striking change in the distribution or rate of growth of 

 the whitefish has taken place, it seems probable that the 1959 year class was not 

 a strong one. Some 4735 whitefish from 85 commercial catches were examined 

 during 1962. The observations from the summer experimental gillnetting program 

 similarly did not include significant numbers of fish in the size range of normal 

 two-year-olds, which may suggest that the following 1960 year class was also weak. 

 The members of the large 1955 and 1957 year classes were readily caught at the 

 same netting locations in 1957 and 1959. The whitefish catch-per-unit effort was 

 substantially reduced this year from the 1961 level (which was affected by the 

 absence of age 2-sized fish). These observations would admittedly be more con- 

 clusive if based on age determinations, but the lack of evidence of gross growth- 

 rate change in a wide range of past year class sizes lends quite a high probability 

 that they are reliable. Two weak year classes in succession can be expected to 

 reduce the commercial catch at least through 1963 and early 1964. Since the 

 whitefish is the only species remaining to this fishery, such a gap could have a 

 serious economic impact on the industry. 



This information from the 1962 research, coupled with the information 

 reported last year on the importance of adequate spawning stock, led to a recom- 

 mendation adopted by management for a restricted harvest of whitefish as a means 

 of improving the future outlook for this fishery. 



The lake trout project was designed to assess the possibility of re-establishing 

 a commercially useful population of lake trout in eastern Lake Ontario with a sea 

 lamprey population continuing to exist in the area. 



This program entered a new phase this year. After a large number of small 

 plantings, it was possible to conclude only that: 



(a) there were no indications of recruitment from natural spawnings. 



(b) survival of the introduced trout has been good in recent years. 



(c) the whitefish fishery catches significant numbers of the planted trout 

 incidentally. 



(d) the number of fish surviving to reach sexual maturity was in all 

 probability very small. 



It was suggested that the last point be examined by making two plantings of 

 at least 100,000 yearling fish in successive years to terminate the experimental 

 series. A request for the fish, forwarded to the Great Lakes Fishery Commission, 

 was recently granted, and the first planting of 100,000 fish is to be made in the 

 spring of 1963. 



As was reported in 1960 and 1961, the walleye (yellow pickerel) study in 

 the Bay of Quinte was restricted to the accumulation of data on a routine basis. 

 This procedure was repeated in 1962 and while it allowed provision of information 

 of immediate value to management locally, proper analysis to allow broad applica- 

 bility of the results awaits additional scientific staff. 



251 



