British Reptiles and Amphibians 



personally responsible. Hence his expenditure of 

 money in this peculiar way. 



Nature never inflicts upon a country-side a plague 

 of Snakes, nor does it multiply obnoxious insects, 

 unless some upheaval has taken place in the well- 

 ordered plan of the seasons. Increases and decreases 

 of a striking character are generally the outcome of 

 abnormal conditions, in many instances the work of 

 artificial interference. When the farmer's fields some 

 years are overrun with hordes of destructive Voles, it 

 may reasonably be surmised that the conditions under 

 which the Voles live and increase in numbers must be 

 more congenial than in an average year. The same 

 deduction might be made in other visitations of a like 

 nature. When a superabundance of Voles exists in 

 any one year, there, too, the Kestrel Hawks gather 

 themselves together. The desire for food is their 

 talisman. When a creature secures a sufficient quantity 

 of food, its own race increases relatively. The suc- 

 ceeding year finds a larger number, which demand 

 more food, and thus the balance of field-life is being 

 constantly adjusted. It may be, as is often asserted, 

 that the game preserver has killed off many of the 

 mammals and birds that help to keep that balance 

 true ; but of this there is no doubt, if Nature was 

 left undisturbed, fewer records of Vole plagues or 

 abnormally large numbers of Snakes would be written. 



The extermination of many mammals and birds that 

 formerly inhabited the British Isles was the result of a 



32 



