HIBERNATION 



IT is instructive to look over the list of British Mammals 

 and to inquire what solution each offers to the 

 problem of Winter. The migratory birds' solution of 

 evading the hard times altogether is not open to any 

 mammals except bats, and we have few facts regarding their 

 migration. Some of our mammals lay up stores and do not 

 hibernate, e.g. the harvest-mouse and the wood-mouse ; 

 others lay up stores and also sleep, e.g. the field-vole and 

 the squirrel ; others neither store nor sleep, but turn white, 

 e.g. stoat and mountain hare ; others neither store nor 

 turn white, but hibernate, e.g. hedgehog, common shrew, 

 and bat ; others again do nothing but brave the rigour 

 of the Winter, e.g. fox and polecat. The mole occupies a 

 somewhat peculiar position, since it can continue its work 

 and find food below the reach of the frost ; moreover, it 

 sometimes makes a store of earthworms which form a staple 

 part of its diet . The water-shrew is another non-hibernator, 

 and we can understand this since the thorough freezing up 

 of rivers or even streams is a rare occurrence. What we 

 see in going over the entire list is, that those which do not 

 hibernate have usually some other marked adaptation 

 to the Winter, such as the habit of storing or of changing 

 colour. In default of anything of this sort and of a callous 

 constitution which can defy storm and scarcity, the animal 

 may save itself by hibernating. It passes into a state when 

 it can starve without feeling it, it lies low with dulled 



sensitiveness instead of fretting itself to death in a struggle 



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