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Rh 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 very 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 in the shape of various seeds. When they are very hard pressed, as 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,