174 The Ruffed Grouse 



DISTRIBUTION OF BIRDS AS AFFECTED BY FOOD SUPPLY 



The distribution of grouse is affected by the food supply both 

 daily and seasonally. Each morning, weather permitting, the birds 

 leave their roost, selected for its shelter value, and seek the food- 

 producing covert most readily available. This may be right w^here 

 they roosted, but more likely it is a little distance away. Again at 

 evening the feeding coverts are sought, after which the biids retire 

 to the roosting place. Thus the proper location of feeding coverts 

 with respect to shelter is of immense importance in determining the 

 carrying capacity of an area, since both must occur within the daily 

 cruising radius of the birds and must be suitable for all seasons of 

 the year. 



In a more extensive manner the location of certain types of food- 

 producing coverts affects the seasonal distribution. Overgrown land, 

 particularly that with preferred foods such as the fruits of hawthorn 

 or dogwood, markedly affect the range of grouse in the fall. Slash- 

 ings and some types of overgrown land draw many grouse during 

 the summer, while in the spring the hardwood woodlands probably 

 have their greatest effect on distribution as affected by food habits. 

 Food supply has least effect in winter, when widely available buds 

 are the dominant food and shelter the prime need for existence. 



EFFECTS OF CULTURAL OPERATIONS ON THE 

 FOOD SUPPLY 



It is well recognized that the workings of man may have profomid 

 effects on grouse range. What are the effects on the food supply of 

 the birds? Let us consider this question for each of the important 

 cultural practices. 



Lumbering: Woodland cutting practices change the food condi- 

 tions of a woodland in proportion to their severity. In some respects 

 food supplies for grouse may be increased, in others, decreased. The 

 cutting of a growth of mast-producing trees, as oak and beech, re- 

 moves it from production for decades. This is probably the most 

 serious destructive effect of lumbering on the food of the grouse 

 and is most injurious in the southern part of the range. In the same 

 way, lumbering takes some of the important bud-supplying species 

 as cherry, poplar, and birch, out of production for several years. A 



