COVER REQUIREMENTS OF THE GROUSE 147 



less, although they still are frequented more than any other type even when the birds are 

 nearly full grown. It is as though with grouse, as with humans, "variety is the spice of life.' 

 As will be seen in the next chapter, even the young birds are omniverous in their choice 

 of food. No one has, as yet. been able to determine whether the birds choose the more com- 

 plex types of undergrowth because of the better food and sheher provided there or whether 

 the variety of their bill of fare is the result of their preference for such a habitat. Such con- 

 jectures, while interesting, are never open to exact proof. Even in favorable locations, it is 

 seldom possible to find any one type of undergrowth so completely dominant as not to be 

 broken up by small patches of other tyjies in which the birds might find food and shelter as 

 desired. Other conditions being favorable, the combination of young hardwoods with shrubs 

 and berry bushes seems to represent an undergrowth i ondition quite acceptable to most young 

 grouse. 



Effect of Density of Undergroiclli on Brood Cover Choice 



Remembering that young grouse are variety seekers in their choice of undergrowth types, 

 one might anticijiate the existence of a strong preference for those areas where the cover 

 is both luxurious and dense. In actuality, whether the undergrowth is sparse or dense but 

 otherwise attractive, it appears to be about equally well patronized. The larger number of 

 broods found in undergrowth of medium density may be explained by the larger amount 

 of this classification to be found on the areas studied. Likewise, areas of sparse under- 

 growth were more extensive than were the denser thickets or tangles so characteristic of 

 some clear-cut woodlots. This being so. in analyzing table 113* one detects a tendency to 

 prefer cover types where the undergrowth is at least fairly dense. 



Perhaps the age of the brood, too, may influence this choice somewhat for areas where 

 the cover is s])arse appear more attractive to the younger age groups, whereas the denser 

 tangles are more likely to contain broods as they mature. 



But the tendency is not so strong as to warrant much time and effort being spent on cre- 

 ating such coverts, should areas of dense undergrowth be lacking. The table clearly indicates 

 that broods, irrespective of age, will make use of any of the three categories. 



The Effect oj Weather on the Type of Undergrowth Chosen by the Brood 



Weather exerts its effect on all cover types, irrespective of acreage. This reduces somewhat 

 the probability of error in determining the brood use-undergrowth type relations under vary- 

 ing conditions of temperature, atmospheric conditions and wind. 



Analyzing the first of these factors, one notes (table 1441^ an inclination for the broods 

 lo frequent open fields, characterized by large herbs, most commonly on warm days. Con- 

 versely, in colder than normal weather they seem more likely to seek the shelter of the larger 

 hardwoods, and occasionally those admixed with conifers. At such times the "combination 

 type," characterized by a variety of vegetation, seems distinctly less attractive to birds than 

 on normal or warm days. 



No really significant change in use is noted in the "shrub and berry bushes" type so 

 characteristic of slashings, as a result of temperature changes, nor is there more than a 

 very slight tendency to use "conifers" more on warm days than on cold days as was found 

 to be the case when the crown cover was made up largely of evergreen species. 



* See Appendix, p. 809. 

 A See Appendix, p. 810. 



