138 COl'ER CHARACTERISTICS A\'n SHELTER REQUIREMENTS 



It is encouraging to find no important difference here, for woods' roads represent an in- 

 tegral part of most woodlands which it is wise to maintain in the interests of providing more 

 favorable nesting cover. 



The surprising thing about grouse nests is that so few cover influences seem to strongly af- 

 fect them, either as regards location or fate. As pointed out elsewhere, the ruffed grouse has 

 survived over a period of at least 25.000 years. Ample opportunity has thus been provided 

 for the species, either to develop highly specialized habits and requirements or to become so 

 adaptable as to fit into many different situations with reasonable success. Here is evidenre that 

 the latter is the case. 



Brood Cover and Related Influences 



Turning from nests to broods, an even greater variety of questions arise. What types 

 of cover most nearly meet their needs? How does this change with age, sex. seasons, weather, 

 and with the time of day? What undergrowth conditions are to their liking? Are they par- 

 tial to particular slope situations? These are but a few in need of answers. 



As long as one is discussing nesting cover, the ])robleni of recognizing grouse needs in terms 

 of usage is not particularly complicated. It has been assumed, based on the collective expe- 

 rience and judgment of the authors, that most types of cover were usually available to the fe- 

 male in which to nest if she chose and that the best liked one was selected. Thus use became 

 directly interpretable into choice. 



With broods and adults, the picture is scarcely as clear cut. Their requirements change 

 with age, sex and the seasons. So also does the ability of the cover to satisfy them. A newly 

 hatched chick, feeding largelv on insects and unable as vet to flv. is iiaturallv interested in a dif- 

 ferent food and shelter combination than is a ten-week-old bird su])sisting on leafy material 

 and fruits and quite able to take care of itself. An overgrown field may offer satisfactory 

 refuge in summer yet fail completely to afford adequate shelter against winter weather. 



Other complicating factors exist. The quantity, quality and arrangement of cover are dif- 

 ferent in each individual covert. This means that broods and adults mav not be able to exer- 

 cise a free choice of cover types, undergrowth conditions and slope iiecause such are not 

 equally available to all at the same time. 



Furthermore both quality and quanlit\ of cover t>pe var\ with tlic seasons and over the 

 years. The latter may often pass by the unwary investigator unrecorded with tlic resuh that 

 he, also, may not be able to exercise a free choice of cover type data. 



As a bird matures it gradually establishes its own territory, into which it. at times, resents 

 intrusion by other grouse of the same sex. The jiest habitats may be fully occupied, thus 

 forcing some birds to establish their tcrritoric-^ in the less desirable |)arls of a comtI. tliout;b 

 not from choice. 



To make interpretation doubly dillicult. the iirobabilit) of obseiM'd brood or adult reac- 

 tions not being typical is directly proportional to the disturbance of the normal response 

 caused by the itucstigalor in the course of his work. 



One cannot design and carrv out a cotnprehcnsiM- study of the grouse and still fully com- 

 pensate for the effects of all these complications. Their influence, however, may be minimized 

 by securing a large number of records covering a iiNiiiiMr of \ears from earli of the repre- 

 sentative grouse haliitats over the State. From thcsi' the significant trends usually can be 

 deterinincd. This was the j)rocedure followed in ascertaining such items as cover preferences 



