THE LIFE HISTORY OF THE GROUSE 25 



is of rare occurrence. It is obviously impracticable to induce the Grouse to 

 change this dangerous practice of congregating in packs ; but in another part 

 of the Report suggestions are offered for minimising the risk of disease by 

 distributing and increasing the areas to which the packs may resort for food.^ 



In autumn, where a moor is near arable land, the birds will often come to 

 feed on the stubbles and corn stooks ; they sometimes come in hundreds, and 

 from long distances. This is not, however, the universal rule, for in some 

 districts Grouse feed ver}^ little upon the corn, and in some seasons they appear 

 to frequent the arable land more than in others. It has often been observed 

 that by improving the heather on a moor Grouse may be induced to feed less 

 upon the stooks. The change is often accompanied by an improvement in the 

 health of the stock, and this has given rise to the view that corn is an 

 unwholesome diet for Grouse.' 



In very severe weather the Grouse leave the high grounds entirely, and 

 remove in packs many miles to the lower moors where they can find "black 

 ground," or to a hill plantation where they can pick up a bare sustenance seasonal 

 in the shape of various seeds. When they are very hard pressed, as '"'S'-'^ wn- 

 in the winter of 1894, they even flock to the turnip fields, and instances of their 

 alighting on thorn hedges to pick the haws are recorded in the Field of that 

 year. In Argyllshire they have been known to feed on birch twigs during 

 the winter — settling on the trees to reach the woody buds. 



The subject of the migration of Grouse is one which has engaged the attention 

 of many naturalists ; but there has been a tendency among observers to note 

 only the abnormal cases, and from them to deduce a general rule. One great 

 obstacle in the way of accurate observation is the difficulty of identifying the 

 original point of departure of the wandering packs. In spite of the confident 

 statements of gamekeepers that they can tell by the size and plumage of a bird 

 that he has come from a certain district many miles away, it is more than 

 probable that the newcomer has always had his habitation within a few miles 

 of the neighbouring march, or even that he has never left his home, but has 

 disguised himself by a sudden moult. In some districts undoubtedly the birds 

 shift annually in vast packs from the high ground to the lower moors, and 

 return again in the spring to breed. 



On rare occasions migration takes place upon a much more serious scale, 



' Vide cliap. xvii. p. 392. 



^ Vide cliap. viii. pp. 178-180. 



