THE PLAGUE OF FIELD VOLES IN SCOTLAND. 133 



hood during the last ten years, having " developed most marked 

 carnivorous habits, taking eggs, young birds, young poultry, 

 young (hares and rabbits, to an extent they never did before." 

 Simultaneously with this manifestation of Carrion Crow-like 

 habits, Mr. Service had noticed an increase in the number of 

 Rooks with feathered faces like the Carrion Crow, which he was 

 inclined to connect with the change of their diet. (See Stevenson's 

 ' Birds of Norfolk,' vol. i. pp. 274, 275.) 



This alleged modification in the habits of the Rook, though 

 favourable to the farmer, has not unreasonably brought him into 

 evil repute with game-preservers. 



Amongst other birds which have been observed to prey on 

 voles are certain species of Sea-gull. 



Stoats and Weasels are among the deadliest and most 

 persevering enemies of small rodents. They kill far more than 

 they can devour, apparently out of sheer blood-thirstiness. In 

 woodlands and on low ground they undoubtedly do much harm 

 to game, especially the Stoat, which may be easily distinguished 

 from the Weasel (known in Scotland as the " whittret ") by its 

 greater size and by the black tuft at the end of the tail, which is 

 retained at all seasons of the year, even in winter, when the rest 

 of the body becomes wholly or partially white. 



Adders feed readily on voles, and in July, 1892, the Chairman 

 of the Committee was present when one was killed with a vole in 

 its gullet. This was in Wigtonshire, where no abnormal increase 

 in the number of voles has been observed. But a single Adder 

 would probably not kill more than one animal of the size of a 

 vole in a single day : so there is no reason to extend protection 

 to these venomous reptiles. 



Some naturalists aver that the Mole preys upon voles ; but 

 the Committee, though directing inquiries upon this point, were 

 unable to elicit any evidence tending to confirm this belief. 



The popular opinion that the excessive multiplication of Field 

 Voles is the direct result of the destruction of birds of prey, 

 Stoats and Weasels, which has been admittedly great over part 

 of the affected area, does not appear to be generally the outcome 

 of personal accurate observation. 



The Committee are of opinion that birds and beasts of prey, 

 even had they been wholly unmolested, would not have prevailed 

 to avert the vole plague, though they would probably have greatly 



