200 The Ruffed Grouse 



foxes on Connecticut Hill has averaged about one in five. The per- 

 centage of predator-destroyed nests attiibutable to foxes varied 

 much from year to year but averaged forty-three and five-tenths per 

 cent over the whole state as summarized for two hundred and thirty- 

 nine such nests observed from 1930 to 1934 {N. Y. S. Cons. Dept. 

 Ann. Rep., 1934). 



The records of foxes taking young grouse have been very few. It 

 should be noted that until the birds are nearly half grown they are 

 probably eaten whole, thus leaving no evidence. But even though 

 summer food habits of the fox have not been well studied from 

 stomach contents, circumstances indicate that foxes are not impor- 

 tant as predators on grouse chicks at this season when other food 

 is plentiful. 



With the advent of winter the fox once again becomes a serious 

 enemy. From autumn through spring the toll of adult grouse taken 

 by foxes is significant, the greatest numbers being captured from 

 midwinter to midspring. The number of grouse that are killed by 

 foxes in the winter is somewhat dependent upon the weather. With 

 deep snows, the grouse resort more to the snow for roosting; there 

 some of them will certainly be found by foxes. The vulnerability of 

 grouse in snow roosts is great. One of our observers, upon noticing 

 one day that many birds in snow roosts flushed at very close range, 

 determined to try to catch one by hand. Of the next three birds he 

 saw in snow roosts he was able to stalk and catch two, and the third 

 barely escaped. A fox too can learn to locate the bird by the slight 

 snow mound at the end of a grouse track, and surely it can outdo a 

 man at stalking. 



The proportion of grouse lost through predation on Connecticut 

 Hill that is attributed to foxes averaged twenty-one and four-tenths 

 per cent of one hundred and ninety-one remains for which the enemy 

 was identified {N. Y. S. Cons. Dep. Ann. Rep., 1933). The propor- 

 tion of adult mortality ^ resulting from predation is about ninety-five 

 per cent. As grouse mortality averages some forty per cent for the 

 same period, foxes kill nearly ten per cent of the total population. 

 In considering these figures we should not overlook the possibility 

 that some of this apparent prey may have been carrion, or crippled 

 or sick birds. However, it is our considered opinion that making 

 such an allowance would not affect the figures materially. 



^ Aside from human destruction. 



