OBSERVATIONS ON THE FOOD OF GROUSE 77 



Probably the consumption of other foods, which are classed under " various," 

 and have already been enumerated, varies 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 Derbyshire, where 

 it reaches 40 per cent, of all foods taken. 



Individual taste pla3'S 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 IV. 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 shoots'the 

 but heather shoots constitute the diet of the Grouse during February ?^ Febru- 

 and March — the fact that the February column shows 7 per cent, of March 

 " 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 that 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 sufi"er 

 either by direct starvation, or what is much 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 crops at all, perhaps from stress of weather, or possibly because of 

 excessive or deficient burning or an overstock of sheep, or for some other less 

 obvious reason. 



The mere fact that the crops of many birds contain old heather is enough 



