THE LIFE HISTORY OF THE GROUSE 15 



up to the end of July, not very far from where it was hatched out. Then, 

 again, it is difficult to explain how on a large moor the young birds have departed 

 before they are capable of sustained flight, especially if none of the neighbouring 

 moors have received any noticeable addition to their stock. Lastly, it is per- 

 missible to ask how is it that when the young birds emigrated to more congenial 

 surroundings they omitted to take their parents with them ? Each of these points 

 presents a difficulty, and the combination of them renders the migration theory 

 untenable as an explanation for the absence of birds at any time up to the 

 beginning of August.-' 



Another favourite theory is that all the young birds have been drowned, 

 and if it so happens that there has been a severe thunderstorm in 

 June the theory becomes a certainty — though not a single drowned '"' 



chick may have been found on the moor. 



There is no doubt that many young Grouse are destroyed by drowning, 

 either as a result of being caught in a drain by a heavy shower, or by the 

 flooding of low-lying ground. It is difficult to estimate the loss gi^eep 

 occasioned by drowning in sheep drains, owing to the extreme '^^>"^- 

 difficulty of detecting the small corpses in the swollen stream. One of the 

 Committee's correspondents, a gamekeeper, who makes it a rule to inspect all 

 the drains upon his ground several times during the nesting season, states 

 that on one occasion only has he found a drowned chick in a drain. This 

 evidence is, of course, only negative, and against it has to be reckoned the fact 

 that many observers have spoken definitely as to the damage arising from 

 this cause. On many moors the sheep drains have been scoured by floods 

 into deep chasms, from which it would be difficult for the chick to emerge on 

 the approach of danger, and any one who has seen a hill drain immediately 

 after heavy rain, when it is running bank high in a miniature torrent, can 

 picture the risk which might attend any attempt on the part of the mother 

 bird to lead her brood over the obstacle. Much may be done to minimise 

 this risk by forming little backwaters in the drains with shelving banks, by 

 which the young Grouse may escape in time of danger. With regard to flooding, 

 it is necessary to speak with more reserve. Flooding is a gradual process, and 

 the instinct of self-preservation, which teaches the young Grouse to 

 hide from his foes, will doubtless also teach him to retreat before the 

 rising waters. In one case, however, flooding is a real menace, for if the 



^ Vide vol. ii. Appendix G. 



