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 CHAPTER II

By A. S. Leslie

precise date can be given at which Grouse begin to pair, for this depends more upon the climatic conditions than upon anything else. In a mild winter Grouse will pair as early as December or January; but if, after they are paired, the weather becomes rough and stormy they will again congregate in packs, even after the usual date of nesting has arrived.

The time at which they select their nesting ground (March and April) is also, to a limited extent, influenced by climatic conditions. On high moors, where the snow lies in late seasons till far into the spring, it sometimes happens that during the whole winter, and even up to the month of April, there is hardly a bird upon the hill, the whole stock being congregated on the lower-lying moors where there is "black ground" on which food can be obtained. In such seasons it is interesting to observe the return of the stock to the higher parts as soon as the snow begins to melt. As a rule the birds do not pair upon the low ground, but congregate in packs upon the edge of the snow, waiting for an opportunity of returning to breed on their native hill. A good example of this was furnished in the spring of 1908 on a high-lying moor in Inverness-shire. During the preceding winter there had been a heavy fall of snow which lay for many months on the higher ranges, and drove the Grouse down in vast numbers to the lower levels. On the moor referred to there was not a Grouse to be seen until the snow began to melt about the end of April. But at the first sign of thaw the stock began to return, and as each patch of bare ground came into sight a pair of birds arrived as if guided by instinct and commenced to nest. This year the shooting season turned out to be a record one, for upwards of Rh