estimated from hunters' reports. These data are now being analyzed to establish 

 mortality rates and population trends. 



Additional studies were made of the effects of snow on the movements of 

 deer and a compactability gauge, to measure supporting strength of snow and 

 crust, was designed and tested. Data from 130 snow stations throughout the 

 province were compiled and used in estimating over-winter survival of deer. 

 Snow depth data are passed to, and published by, the Canada Department of 

 Transport. 



A moose checking station, operated on the Red Lake Road (Kenora) 

 obtained data on 535 moose. A measure of the effects of very heavy hunting 

 pressure on the moose population in this area was obtained and this has now been 

 published. 



Studies of methods for aging moose were continued; counts of cementum 

 rings in the incisors of moose showed considerable promise and 350 were aged by 

 this method. The weight of the eye lens was also tested as a means of determining 

 age. 



Research on woodland caribou was continued using aerial surveys of 

 populations and examination of specimens received from Indians. The results of 

 these studies in 1964 were published. A detailed cover-type map of the Patricia 

 Districts north of latitude 54° was completed in co-operation with a graduate 

 student at Guelph University. 



Predators 



The Algonquin Park research programme on timber wolves was completed 

 and the results were prepared for publication. Timber wolf research was continued 

 in the Pakesley area of Parry Sound District in an effort to measure the combined 

 effects of hunting and predation on prey populations. Of particular interest was 

 the seasonal difference in prey species taken by wolves; deer were important prey 

 during the winter months, but beaver constituted the largest item during the 

 remainder of the year. There was no evidence that this was having an adverse 

 effect on beaver populations. 



Additional predator control officers were trained during field work of the 

 research programme and 25 are now available for control work in the central and 

 southern parts of the Province. 



Research on bears was expanded as certain projects in the timber wolf 

 programme were concluded. A great deal needs to be learned about the ecology 

 and population structure of black bears in Ontario and several projects have been 

 initiated to study movements and ranges, the effects of hunting on them, the 

 characteristics of population fluctuations and the effects of their predation on live- 

 stock. 



Aerial surveys of polar bear populations showed concentrations in the areas 

 of Cape Henrietta Maria and the Pen Islands as in 1963 and 1964. Numbers 

 were down, however, from previous years. Estimates also showed that cubs were 

 fewer; they formed 17% of the population in the summer of 1963, 13% in 1964 

 and only 5% in 1965. It is not yet known, however, if these changes were real or 

 resulted from differences in bear behaviour and distribution from year to year. 



REPORTS 



Research Branch reports published during the year ending March 31, 1966. 



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