There is a world somewhere between reality and fiction. Although ignored by many, it is very real and so are those living in it. This forum is about the natural world. Here, wild animals will be heard and respected. The forum offers a glimpse into an unknown world as well as a room with a view on the present and the future. Anyone able to speak on behalf of those living in the emerald forest and the deep blue sea is invited to join.
04-14-2015, 09:56 AM( This post was last modified: 04-14-2015, 11:16 AM by peter )
Copters,
When replying to your post on the weight of the young male tiger, things, ehhh, got a bit out of hand. I quoted your post, meaning it was on top of the post. When I posted my reply, however, I noticed the identities had been swapped, meaning my post was posted under your name. In order to prevent questions, I decided to delete it. This means your post also was deleted. Sorry about that. Maybe you can give it another try?
My response wasn't about the weight of the young male tiger, but about your remark on then and now. Not much to choose, you wrote. I partly agree. I didn't see any difference between then and now in north and northwest India. South, central and northeast India, however, could be a bit different. The Nagarahole male tigers measured and weighed by Ullas Karanth in the nineties of the last century averaged 298,00 cm. and 217-218 kg. (adjusted). My guess is they are a bit heavier than a century ago. Same for central and northeast India. The question is why.
Central India has many smallish reserves, excellent conditions and little or no space to accomodate tigers outside the reserves. The result is conflict over space and quite many casualties. If this pattern continues for some time, the reserves might develop into a training facility for would-be gladiators preparing for their all-out in the Roman Circus. Only the best fighters will last long enough to pass on their genes. In the long run, this will probably result in slightly more robust tigers and more pronounced sexual dimorphy. And guess what? I don't think males will evolve into bear-tigers, but it's likely they adapted to the unslaught by adding a few extra pounds. Robusticy is mostly about size and extra weight will result in a larger size. My guess is the difference (in weight) between then and now in most parts of India would be about 5-10% (average 7.5%). This, of course, is just an assumption.
Nagarahole is different. The reserves are larger and there are corridors, meaning conflicts over space would be less frequent and less serious. The large size of today's tigers, therefore, wouldn't be an adaption to conflict, but a result of diet. The average prey size of Nagarahole tigers is impressive.
All in all, today's adult males could be a bit larger than a century ago. The reason is better conditions, larger prey animals and more competition. If they averaged about 195 kg. in (all of) India about a century ago (regional range 182-209 kg.), today's average, after adding 7,5% (the assumed increase in weight), would be 210-212 kg. (regional range 190-225 kg.). Tigresses most probably didn't change very much in the last century.