PSYCHOLOGY AND BEHAVIOR 63 



Under starvation conditions birds which were heavier at the start maintained their weight 

 better than did lighter individuals. Weight loss was greater for all birds at night than during 

 the day time. 



Under normal conditions food was found to pass more slowly through the alimentary tract 

 as the environmental temperature dropped. 



Finally an effort was made to determine the amount of food needed by an adult grouse to 

 maintain its weight under average living conditions. Since differences in composition between 

 various foods cause their fuel values to differ, a standard unit of measurement, the calorie, 

 was used for comparison. It was found that, for the birds studied in this experiment, a food 

 consumption having a value of 78 calories per day should result in their neither gaining nor 

 losing weight at an environmental temperature of 65 -F. when not subjected to exertion. 



PSYCHOLOGY AND BEHAVIOR* 



Each activity of a living organism is a component of its behavior. Reactions are largely 

 the result of an animal's physiological and psycholopicai makeup in response to external 

 stimulation coming from the habitat in which it lives. Therefore, a wildlife manager must 

 understand and take into consideration as many of the patterns of behavior as he can if he 

 is to take full advantage of the possibilities of increasing wildlife abundance through devel- 

 oping and managing its environment. Yet, with most game species, grouse included, very 

 little is known about these basic relationships. 



The Investigation has had an abundant opportunity to note grouse behavior in the wild 

 and in captivity. Consideration of the pertinent observations gathered therefrom falls logi- 

 cally into two categories. Either one may desci ibe the actions of the birds under various 

 circumstances primarily from the standpoint of a disinterested spectator, as in Chapter V, or 

 one may go beyond that and attempt to understand such behavior in terms of its significance 

 in the life of the bird. The psychological aspect of the latter approach seems sufficiently 

 distinct to warrant special alli-nlidn lure. 



Two such behavior patterns have become clearly enough defined to merit description. The 

 first is the social order; the second, that of mating behavior. 



It should be recognized at the outset that it is difficult and ofttimes misleading to attempt 

 an analysis of animal psychology, based on behavior, because of the inevitable tendency to 

 interpret reactions in terms of their human counterparts. Likewise, pitfalls beset one in 

 trying to evaluate observations made of captive individuals, which of necessity have been the 

 basis of much of this discussion with respect to grouse. Realizing this, no suggestion as to 

 their degree of applicability to birds in the wild is contemplated here for. in doing so. one 

 may be guilty of ascribing to such birds responses possibly induced in their hand-raised 

 cousins to some extent by the artificial conditions under which they are held. On the other 

 hand, the reactions here described are basic and almost certainly are to be found among wild 

 birds as well as among those held in captivity. Let us then depict them here. 



The Social Order 



The ruffed grouse may not normally be considered a gregarious or social bird. Yet from 

 the time the chicks are first hatched until well into the fall, numbers of individuals are 

 found together either in the loose association of the brood or, very occasionally, in so-called 



* By Gardiner Bump. 



