CLASSIFICATION AND LIFE HISTORY 5 



where the fall occurs after the birds have returned to their 

 nesting ground on the higher ranges. This occurred on a 

 moor in Ross-shire in the year 1909, when a correspondent 

 of the Committee reports as follows : "A heavy snowfall on 

 April 24th put all the birds down to ' black ground.' They 

 never went back to nest, and consequently the high ground, 

 i.e., over 500 ft., was a failure, and the low ground better than 

 usual." Again, a correspondent in West Perthshire writes : 

 " In spring, when the breeding season is approaching, a heavy 

 snowstorm of some duration has on several occasions caused 

 a most serious loss of stock, amounting to as much as half 

 or more of the whole number of birds. After such a spring 

 snowstorm and migration, large numbers of Grouse undoubtedly 

 remain to breed on low and favourable moors within, say, 

 ten or fifteen miles. These low moors are very heavily shot 

 every year, but there is a constant migration of Grouse to them, 

 both from overstocked moors, and from the high moors affected 

 by snow." This is corroborated by a correspondent in the 

 south of Scotland, who says : "I have an idea that if birds 

 are forced to leave their usual ground (in spring), through deep 

 untrodden snow, a good number may remain away and not 

 return to their former ground." 



The subject of migration is more fully dealt with in another 

 part of this chapter. 1 



During the mating season the pugnacity of the cock Grouse 

 is well known, and in captivity the cocks have to be kept separate 

 at this period, or disaster will certainly occur. Under natural 

 conditions the fights seldom end fatally ; but it is certain that 

 the presence of a quarrelsome cock-bird in search of a mate 

 seriously interferes with the pairing of the other birds in the 

 vicinity. Observation in the field goes to prove that old 

 cocks are more pugnacious than young ones, and as they are 

 less valuable for breeding purposes, the object of every moor- 

 owner is to reduce the number of old cocks by every means 

 in his power. 



1 See pp. 29-32. 



