ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)

[peter]

PUGMARKS

INDIA

Those loaded with experience regarding Indian tigers agreed tigers inhabiting low-lying regions, as a rule, leave larger prints than tigers living in more elevated regions. They usually also grow to a larger size, but there is reliable information on hill-tigers of ten feet and even over. One ten-footer shot a century ago, in spite of its immense weight, left prints not much larger than those of an average male leopard. This tiger had lived in hill country all his life. 

RUSSIA

Amur tigers, for about six months of the year, have to deal with snow. In one region in central Sichote-Alin, the average snow depth in the seventies of the last century was no less than 38 cm. In some parts of the region mentioned above, the snow depth was much more.

Large paws act like snow shoes in that they allow the tiger to move in difficult conditions. It is in winter many Amur tigers seem to flourish and it could be paws, to an extent, are involved.  

DECIDING FACTORS

Amur tigers, like Indian tigers, inhabit low hills. This, judging from India, would have to result in smaller paws. Not so. This means snow, in Amur country, outweighs hills regarding paw size. 

Although Sichote-Alin is more elevated than most of India and also has large tracts of forest, the vegetation is different. Not as dense and not as dry. The need to contract the foot muscles wouldn't be there, that is. It could be this is a factor to consider regarding Sichote-Alin, but my guess is snow depth would be the most important factor.

BERGMANN

Bergmann's rule seem to have lost a lot of weight in biology, but it explains many differences between regional types in mammals. The long body enables Amur tigers to keep warm in serious cold and the long feet allow them to hunt in deep snow. Furthermore, it explains why island tigers are smaller than mainland tigers. We would need a few extra rules to understand specific phenomena (dwarfism in Bali and outsized specimens in some parts of India), but Bergmann isn't as bad as many suggest. Reply