to the same biological family as rats, mice and hamsters.> Lemmings live – and rear their young - in burrows; but they do not hibernate during the winters. As a result of their incessant activity, they need large quantities of food to sustain them.
The lemmings multiply rapidly – they have litters of upto eight young, and more than one litter per season. They are ravenous creatures that eat the land bare; and their territory soon becomes overcrowded. Bereft of food, famine follows a time of plenty. Driven by hunger, the lemmings begin to assemble in groups and move outwards towards the sea. When they reach the sea, none returns… The few lemmings that survive in isolated areas begin to increase in numbers again – and the whole cycle repeats itself.
Lemmings breed in the wild, unpopulated regions of Scandinavia. And though the lemmings often move through the northern part of Scandinavia in large swarms, they are rarely seen – or photographed. The lemming fears neither man nor beast. But, the author says that nature employs various means to keep the numbers of different species in check; that is why one must be careful not to disturb the balance of nature.
Panic takes hold of the lemmings – and their migration turns into a stampede that resembles the proverbial march of death. Though many thousands are killed, it makes no difference to them as their numbers are so large. When they reach the sea, they swim outwards towards some (long submerged) promised land. These mass migrations are the result of an instinct acquired over thousands of years; when their forerunners used to migrate towards a once dry land in the North Sea.