Food and Water 103 



It will be noted that the chicks start off with a full insect diet, but 

 soon add fruit to their fare. By the time they are a month old they 

 are consuming green food and by midsummer insects make up less 

 than half the diet. Toward the end of the summer, buds are added 

 to the menu and the use of insects decreases rapidly. As with the 

 case of the diagram of adult food types utilized by seasons, the 

 trends in food habits of the young birds had to be interpolated freely 

 in order to get a smooth trend. Except for occasional quick changes 

 in food habits resulting from violent weather, or the sudden ripen- 

 ing of a certain fruit, trends through the months take place quite 

 gradually and therefore properly appear in a graph as smooth 

 curves. 



Utilization of Food Species by Seasons. Compared with that of 

 most wild creatures, the ruffed grouse's diet in the Northeast is well- 

 known. The records given here and the conclusions drawn are based 

 on around 4,000 stomach analyses of birds collected from Virginia 

 and Ohio to Maine as well as upon many supplementary observa- 

 tions. However, because the majority of the specimens are obtained 

 as a by-product of hunting, the records are largely from fall and early 

 winter, and the late winter, spring, and summer material is relatively 

 scant. The New York investigation made collections of adult birds 

 throughout the year, except during the hunting season, in order to 

 obtain the needed food habits information. Young birds as well as 

 adults were collected through the summer. With a scattering of rec- 

 ords from other sources, the year round food habits of the species are 

 now pretty well established. 



The diversity of foods taken by the grouse is indicated by the 

 some 374 kinds of plants and 131 kinds of small animal life already 

 known to be eaten by it in measurable quantities in the Northeast. 

 And yet this list is without doubt far from complete. The author 

 picked up a grouse (killed by a broken neck) in Sullivan County, 

 Pennsylvania, in December, 1940 while deer hunting. Its crop con- 

 tained several fruits of mountain holly {Ilex montana)—a species not 

 previously recorded as eaten by grouse. But this normally rare plant 

 happened to be common on this particular mountain, and the adapt- 

 able grouse appeared to be making good use of it. 



The number of species of insects known to be taken by grouse 

 is doubtless only a small fraction of those that the birds actually eat. 

 Experiments conducted by the State Conservation Department at 



