OBSERVATIONS ON THE FOOD OF GROUSE 75 



of heather seed as a form of food may be seen at a glance from the figures given 

 in Tables III. and IV. 



It is often stated that in seasons when the corn has ripened well and 

 early, the stock of Grouse in the following spring is healthy and vigorous, and 

 the breeding season a good one ; from this it has -been argued that the same 

 weather which has resulted in a good crop of grain has also produced A good 

 a good crop of heather seed. This factor too may have something 

 to do with the difference in the numbers of Grouse which moors 

 in different parts of the country are capable of carrying. It is well year- 

 known that the number of Grouse on a moor does not depend upon the area of 

 heather land, for in the thinly-stocked moors of the west of Scotland the heather 

 growth is stronger than in the south of Scotland, where in many 

 districts there is a larger stock of birds. Even in Yorkshire, Lancashire, 

 and Derbyshire the ground does not appear to be better suited for the 

 growth of heather than in Scotland, yet in these counties the stock of district, 

 birds is proportionately much greater. The difference is partly to be 

 accounted for by the fact already noted, that the heather in the north of 

 England is of a better quality, that is to say with many more stalks to the acre, 

 than the rank growth of the west of Scotland, but it has also been suggested 

 that in the former country the normal weather conditions are more favourable 

 to the ripening of the heather seed. Again, in Caithness, where the grain 

 always ripens well on account of the long hours of daylight in the summer 

 months, the stock of birds which the ground can carry is unusually large. 



In September, October, and November, the tendency to revert gradually from 

 summer to winter diet is well exemplified by the figures in Table III. Throughout 

 these three months the consumption of the heather seed increases steadily, 

 while "various" drops from 16 per cent, in September to 6 per cent, tember, 



in November. In October we find the item of "brown winter heather" and Nov- 

 ember, 

 reappearing in the list, and in November we have a sudden increase 



in the consumption of blaeberry stalks and leaves, due probably to some temporary 

 check suffered by the heather similar to that indicated by the figures for July. 



Turning now to Table IV. (p. 76) we find that in the four winter months the 

 diet becomes more restricted. " Various " practically disappears, and Winter 

 its place is taken by a larger quantity of heather shoots, while heather food ' 

 seeds and blaeberry stalks still keep their place in the list. 



One or two points are worth noting. In the first place, the sudden drop in 



