maskinonge fry supplied from Dorion and Deer Lake hatcheries respectively. Two 

 additional lots of 50,000 maskinonge fry were also supplied to the National Parks 

 Branch of the Federal Government and to the Fish and Game Department of the 

 Province of Quebec from the Deer Lake hatchery. 



Two large scale plantings of marked lake trout yearlings were made in Lake 

 Superior and Lake Ontario in 1963. A total of 476,709 fish were marked and 

 planted in Lake Superior. Some 246,709 of these fish were marked by the 

 removal of both ventral fins and planted in the Rossport — St. Ignace Island area 

 from the Dorion trout rearing station. The remaining 230,000 fish, which were 

 marked by the removal of the adipose fin, were released in the vicinity of White- 

 fish Bay (190,000) and at the mouth of the Dog River (40,000). The Lake 

 Ontario planting was made jointly with the New York State Conservation Depart- 

 ment with 108,000 lake trout yearlings provided by the United States Fish and 

 Wildlife Service from their national hatchery at Charlevoix, Michigan. These fish 

 were marked by the removal of the left pectoral fin before being transferred by 

 Canso aircraft from the Charlevoix hatchery to the Glenora Fisheries Research 

 Station. From here, the fish were transferred by the research vessel Namaycush 

 and planted in the Main Duck Island — Charity Shoal area and at Big Bar Shoal 

 in Lake Ontario. 



A number of special projects were also undertaken in the hatchery program 

 in 1963. The most important of these included: 



WALLEYE POND CULTURE 



The artificial propagation of walleye to fingerling size was initiated at the 

 White Lake hatchery in 1961. This experiment was continued in 1962 and 1963. 



The work carried on during the current year was directed at the clarification 

 of several techniques developed during the previous studies and at reducing the 

 production costs. 



Results from the studies conducted this year indicate that the abundance 

 of zooplankton produced in the White Lake hatchery ponds related more to the 

 average depth of the pond than to the amount of fertilizer applied. Cannibalistic 

 tendencies of walleye fingerlings were also shown to be more closely related to 

 the size and age of the fish than to the abundance or scarcity of zooplankton 

 forms in the ponds. The survival of walleye from fry to fingerling size was 23.1 

 per cent and the average cost was 0.8^^ per fish. 



The Department is presently planning to continue with the production of 

 walleye fingerlings on a limited scale. Initial production will be based mainly on 

 requirements for stocking fingerling size fish for experimental study of survival in 

 natural environments. 



EFFECT OF LIGHT ON LAKE TROUT EGGS 



Preliminary experimental studies to investigate the effect of various forms 

 of artificial fluorescent lighting and natural light on the incubation of lake trout 

 eggs were continued at Chatsworth hatchery. Initial results obtained in 1962 

 showed no significant differences in the rate of mortality or in the condition of 

 the fish in the various lots used in the study. In 1963, the experiment was repeated 

 and the light intensity was increased by removing the glass covers from each of 

 the light fixtures, but again no apparent adverse effect was observed. It is therefore 

 concluded that the fluorescent lighting at Chatsworth hatchery is not harmful to 

 the incubation of lake trout egg stocks at this station. 



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