90 THE GROUSE IN HEALTH AND IN DISEASE 



in the same way chiefly with local relative abundance, as, 

 for example, in Perthshire, where " various " rises to 53 per 

 cent. ; Ayrshire, where it reaches 47 per cent. ; and Derby- 

 shire, where it reaches 40 per cent, of all foods taken. 



Individual taste plays a large share in the food statistics 

 of Grouse. One may find, for example, one bird eating largely 

 of fern leaf, another of bog myrtle buds, another of nothing but 

 rush-heads or tormentilla seed. In one case, where two birds 

 were killed with a " right and left " in a Grouse drive it was 

 found that one had filled his crop with heather shoots, the 

 other with blaeberry leaf buds, yet both birds had come off 

 the same beat. Occasionally one finds that even an adult 

 bird has eaten scores of small black gnats. The flower of 

 Calluna is varied occasionally by the flower of Erica tetralix, 

 or ripe cluster berries, or spore-capsules of several mosses, 

 or leaves of the cloudberry. 



The interest of Table III. centres on the first item, " Heather 

 Shoots," for the figures prove conclusively, if proof were required, 

 that, except on favoured moors where blaeberry abounds, 

 heather shoots and nothing but heather shoots constitute the 

 diet of the Grouse during February and March the fact that 

 the February column shows 7 per cent, of " various " was due 

 to one bird's crop being almost entirely filled with crowberry 

 leaves, a quite unusual diet ; the " various " consumed by other 

 specimens examined for the month only amounted to per cent. 



It is obvious, therefore, that in February, March, and April 

 the question of food becomes a critical one, for if the heather 

 fails the Grouse must suffer either by direct starvation, or 

 what is more dangerous, by being forced to crowd too closely 

 on to the few small areas where good winter heather is to be 

 obtained. 



Although we have no evidence from any one of the hundreds 

 of Grouse crops examined that true frosted heather is ever 

 eaten, the heather which actually filled the majority of the 

 winter crops varied greatly in its value as a food. It could 

 often be seen that the birds had been hard put to it to fill their 



