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

[Shadow]

(08-07-2019, 07:48 PM)peter Wrote:

(08-07-2019, 02:15 PM)RakeshMondal Wrote:

(08-07-2019, 02:05 PM)peter Wrote:

(08-07-2019, 12:31 PM)Shadow Wrote:

(08-07-2019, 07:27 AM)RakeshMondal Wrote:

(08-06-2019, 08:21 PM)peter Wrote: Captive tiger 'Igor' from the Odense zoo was known for his size. My guess is he compared to the Duisburg zoo male Amur tiger. That one was 320 cm. in total length measured 'between pegs' and estimated at 280-300 kg. in his prime:

*This image is copyright of its original author

That tiger is enormous no doubt about that. That guy's head can literally fit in the tigers mouth.

The tiger is really cute awww.

Igor was big, in zoo advertisement it was told to have been 250 kg, about 551 lbs.

http://tourcom.dk/wp-content/uploads/2015/05/OdenseZoo_Aarsrapport2013_4KORR_NY.pdf

One article: https://www.fyens.dk/odense/Usaedvanligt-besoeg-Slingrende-tiger-scannet-paa-retsmedicinsk/artikel/2394807

There are also articles from same time, saying, that 300 kg or almost 300 kg, it variates in different medias. Difficult to say, but when zoo has it printed by themselves, it looks like some reporters have been more accurate than others.

Anyway, big boy.

I saw a video in which Igor, by then well past his prime, was treated for a problem with his teeth. Although large, he didn't seem 300 kg. In his prime, however, he could have been quite close. I'll try to find the video.

This is the video, right?

I found another picture of him training. He looks very large in this picture, very large frame, one of a 250+ kg tiger.

*This image is copyright of its original author

a - Video

No, I was referring to this video: https://www.youtube.com/watch?v=NSR95Lf7MAA

In the video, 'Igor' was well past his prime. Age has quite an effect in tigers in that they often quickly lose a lot of muscle mass. Compare the tiger in the video to the tiger in the photograph I posted. Same animal. 

b - About Igor

In his prime, 'Igor' was both large and robust:

*This image is copyright of its original author

The photographs I have strongly suggest 'Igor' was a bit larger and more robust than Amur tiger 'Jeltzin'. That tiger was actually weighed. In his prime, 'Jeltzin' was 270 kg.:

*This image is copyright of its original author

c - On the effect of old age (and disease) in captive male Amur tigers (in European zoos)

Based on reliable reports and a number of good photographs of different large male Amur tigers, I'd say 'Igor' might have been close to 300 kg. in his prime. In the video, however, he seemed closer to 200 kg. The difference, therefore, could have been as much as 150 pounds (68,04 kg.), if not 200 pounds (90,72 kg.).

I've seen it in more than one male Amur tiger. For some reason, captive male Amur tigers are more affected by old age than captive male tigers of other subspecies. Apparently, it isn't much different in wild male Amur tigers. Just before they perish, they lose a lot of muscle mass.

d - Tigers and muscle mass

What I have on both prime and old male captive Amur tigers strongly suggest that weight largely is a result of muscle mass, not fat. Wild Amur tigers, in order to deal with the long and harsh Russian winter, store fat in late autumn and winter, but it doesn't result in heavy tigers. The heaviest Amur tiger actually weighed, a young adult male of very modest size, was 212 kg. If anything, wild Amur tigers are a bit smaller than their captive relatives (referring to Amur tigers in European zoos). With 'smaller', I mean they're not as heavy.

e - Wild Amur tigers

In long and severe winters, maintaining large muscles could be a costly affair. Perhaps it's more efficient to store fat in order to overcome energy deficiences in winter. In summer, however, fat has no function. 

My guess is the violent fluctuations in weight observed in some Amur tigers were not a result of more or less fat, but something else. Life in the Russian Far East is far from easy. Tiger 'Dale', the infamous bear hunter, ranged between 445 and 375 pounds. That last weight was on a full stomach. Without the roe deer, he could have been 345 pounds. What was the reason he lost about 100 pounds? Nobody knows, but they did notice he lost 3 canines somewhere between 445 and 345 pounds. A fight gone wrong, perhaps? Injuries no doubt have a significant impact on a professional hunter in the Russian Far East. Same for disease.        

f - Food intake, assumptions and adjustments

One often reads stories about wild tigers eating 20-40 kg. of meat in one sitting, but these assumptions could be quite incorrect. According to Yudakov and Nikolaev ('Winter ecology of the Amur tiger - Based upon observations in the west-central Sichote-Alin mountains, 1970-1973, 1996-2010', 2nd revised edition, Vladivostok, 2012), wild Amur tigers are very modest eaters:

" ... Tigers spend from several hours to 3-4 days near a carcass, and use of carcass was not so much dependent upon its size, as upon tiger's level of satiation. It is not uncommon for adult male tigers to consume no more than 25-50% of a kill ... " (pp. 148).

So much for assumptions on actual field weights and the adjustments so many biologists prefer, so it seems.

g - Muscle mass and fat in wild Amur tigers

As for assumptions on fat and muscle mass in wild and captive Amur tigers. In my opinion, too many things are unclear to get to conclusions. Big cats in general seem to have a few secrets in this department. Wild Amur tigers have to deal with heat waves, harsh winters, mountain slopes and powerful prey animals like wild boars and bears. A slight injury could result in less speed and starvation. The conditions no doubt have an effect on their metabolism.

The largest tiger ever shot by the Jankowski's in June or July 1943 (unclear) was at least 300 kg., V. Jankowski wrote in his letter to V. Mazak. In his own book, however, he wrote the tiger was 350 kg. It was a very big tiger by any standard. The photograph didn't show a fat tiger, but according to V. Jankovski the tiger was as fat as they come. It apparently didn't hamper him in any way, as he had killed and eaten a bear just before he was shot. Only the head and a paw remained. I never saw a photograph showing a fat wild Amur tiger, but it could be that fat and muscle are very close relatives in wild Amur tigers. So close, they're all but inseparable.

h - Muscle mass and fat in captive male Amur tigers

All photographs of exceptional captive Amur tigers (those exceeding 600 pounds) show fit tigers. Same for 'Igor', 'Jeltzin' and a host of others of which photographs were posted. For now, based on what I have, my guess is weight and muscle mass are strongly related in tigers. Exceptional tigers are exceptional as a result of a combination between length and muscle mass. Just before they perish, they lose just about everything they have. The only logical explanation is muscle mass.

For some reason, the relation between muscle mass and weight is very strong in tigers. I'm not saying it's different in lions, but I noticed lion skeletons usually are a bit bigger than tiger skeletons, This although the tiger had been heavier in life in every case. One could conclude bones seem to be more important in lions. In tigers, it seems to be muscle mass.

The only reason I can think of is tigers, as solitary hunters, need to be able to adapt quickly to specific conditions. It takes a lot of time to adapt bones. Muscles respond in less than a year, if not sooner. But I readily admit there's not enough to get to good conclusions, meaning we entered the department of speculation.

What comes to that fat layer of Amur tigers, that is one thing, which would be really interesting to know more. We can have different kind of estimations and opinions, but for me it feels just common sense, that Amur tigers as all animals up north have to have more fat in winter than summer. It looks like not too much information available and impossible to make conclusions based on weight changes of some individuals. One individual can be sick at some time causing abnormal weight changes etc. 

Naturally in this extra fat doesn´t mean obese, it´s about something what is necessary for survival in harsh conditions. Quite surprising actually how little there seems to be information about this issue. Or maybe there is some study, but just waits to be noticed. If finding some, Amur tiger thread might be then better place to continue that discussion. Maybe it´s needed to look closer some other animals, which live in same conditions and not hibernating like wolves, lynx etc. They for sure can give at least partial answers if tigers are less studied what comes to physical changes between summer and winter. Tigers aren´t that different after all, just big mammals :) Reply