DISEASES OF GROUSE 119 



at work, that overcrowding in one year or 

 a series of years has of itself directly re- 

 sulted in sudden and decimating disaster. 

 Probably, when disease does obtrude itself, 

 it is felt most and is seen to most dis- 

 advantage on a well-stocked moor ; but 

 this alone is not convincing, but rather a 

 mere question in arithmetic. Again, it is 

 no less the fact that moors which are not 

 fully stocked, certainly not overcrowded 

 with birds, enjoy no immunity from the 

 disease. The same observation applies to 

 moors widely separated from infected 

 overstocked moors. 



In connection with overstocking of 

 grouse reference is often made to what 

 may be called under-stocking of vermin. 

 The point is, that predatory animals 

 which in former years abounded on the 

 moors have been so killed down or 

 reduced that the weaklings among grouse 

 are now to a certain extent protected, 

 instead of being captured and consumed 

 by their natural foes. Thus unhealthy 

 stock is propagated with a strong pre- 



