Who is the "king" of tigers? - Bengal or Amur

[GuateGojira]

(04-03-2020, 01:12 AM)OncaAtrox Wrote: Great image! Could you make one comparing the largest populations of jaguars, primarily Pantanal and Llanos jaguars against Malayan, Sumatran, Javan and Bali tigers? Their sizes appear to overlap so it'd be interesting to see how they measure against each other.

Yes I can. Actually I have an old comparative image of jaguars from the Pantanal and I can tell you that there is some overlap between the Sumatran and Bali tigers. In fact, the Sumatran tigers look like if they are relativelly "lighter" in comparison with other tiger populations, because they are longer than Pantanal jaguars but they overlap in weight very much, with maximum figures of 148 kg for both populations, this was already observed by Dr Helmut Hemmer when observed that Bengal/Amur tigresses with smaller skulls than those of the male Sumatran tigers actualy weight much more with an average advantage of more than 10 kg at least. Now, the Bali tigers and the Pantanal jaguars looks about the same size in the skull deparment (remember that we have only 1 body measurement for Bali tigers and was taken, apparently "over curves"), and based in the pictures available, there is a posibility that they weighed about the same and also that they had the same body measurements. Now, about the Malayan tigers, they are a completelly different league, there are much larger than any jaguar population in modern days, that is for sure.

I am going to make the comparison for you, let's see what we can get. Reply

[Balam]

(04-04-2020, 10:19 AM)GuateGojira Wrote:

(04-03-2020, 01:12 AM)OncaAtrox Wrote: Great image! Could you make one comparing the largest populations of jaguars, primarily Pantanal and Llanos jaguars against Malayan, Sumatran, Javan and Bali tigers? Their sizes appear to overlap so it'd be interesting to see how they measure against each other.

Yes I can. Actually I have an old comparative image of jaguars from the Pantanal and I can tell you that there is some overlap between the Sumatran and Bali tigers. In fact, the Sumatran tigers look like if they are relativelly "lighter" in comparison with other tiger populations, because they are longer than Pantanal jaguars but they overlap in weight very much, with maximum figures of 148 kg for both populations, this was already observed by Dr Helmut Hemmer when observed that Bengal/Amur tigresses with smaller skulls than those of the male Sumatran tigers actualy weight much more with an average advantage of more than 10 kg at least. Now, the Bali tigers and the Pantanal jaguars looks about the same size in the skull deparment (remember that we have only 1 body measurement for Bali tigers and was taken, apparently "over curves"), and based in the pictures available, there is a posibility that they weighed about the same and also that they had the same body measurements. Now, about the Malayan tigers, they are a completelly different league, there are much larger than any jaguar population in modern days, that is for sure.

I am going to make the comparison for you, let's see what we can get.

Can't wait to see the image! Reply

[Amnon242]

(04-04-2020, 10:19 AM)GuateGojira Wrote:

(04-03-2020, 01:12 AM)OncaAtrox Wrote: Great image! Could you make one comparing the largest populations of jaguars, primarily Pantanal and Llanos jaguars against Malayan, Sumatran, Javan and Bali tigers? Their sizes appear to overlap so it'd be interesting to see how they measure against each other.

Yes I can. Actually I have an old comparative image of jaguars from the Pantanal and I can tell you that there is some overlap between the Sumatran and Bali tigers. In fact, the Sumatran tigers look like if they are relativelly "lighter" in comparison with other tiger populations, because they are longer than Pantanal jaguars but they overlap in weight very much, with maximum figures of 148 kg for both populations, this was already observed by Dr Helmut Hemmer when observed that Bengal/Amur tigresses with smaller skulls than those of the male Sumatran tigers actualy weight much more with an average advantage of more than 10 kg at least. Now, the Bali tigers and the Pantanal jaguars looks about the same size in the skull deparment (remember that we have only 1 body measurement for Bali tigers and was taken, apparently "over curves"), and based in the pictures available, there is a posibility that they weighed about the same and also that they had the same body measurements. Now, about the Malayan tigers, they are a completelly different league, there are much larger than any jaguar population in modern days, that is for sure.

I am going to make the comparison for you, let's see what we can get.

Yes. I have seen 2 adult malayan males and 4 malayan females. They are obviously bigger than sumatran tigers and as you said - completelly different league when it comes to comparison to jaguars Reply

[peter]

(04-04-2020, 10:10 AM)GuateGojira Wrote:

(04-02-2020, 10:06 AM)strana Wrote: Guate,
First, thanks for another very interesting material.
However, I think that the size of modern Amur tigers are underestimated. There are some pics of very impressive wild tigers in Russia here in Wildfact; I would not be surprised if some of them reach 250 kg+. I believe only the young/not very healthy are weighted. Wild Bengals and Amur might have similar size, but ok, it is just speculation.

Hello, thank you for your words.

About the size of the Amur tiger, in fact the data on the image takes in count both historic and modern weights. Surely there are photos of very impressive male in the Russian Far East, but sadly none of them has been weighed, so for the moment the biggest male recorded between 1992 to 2012 (the last year when weights were published) was of 212 kg.

Now  about the sample, it is not true that only young or not-healty males were weighed, let me explain to you first. In 2005 Dr Slaght and other scientists published a chapter in the monograph of the Amur tiger published by the Siberian Tiger Project (in Russian only), especifically the chapter No. 6. Now, in that document they calculated an average weight of 176.4 kg (n=18; range: 125 - 205 kg) for males and 117.9 kg (n=13; range: 113 - 129 kg) for females. However those figures includes specimens that were not in good shape, in fact the weight of 125 kg was for male in such a bad shape that was eutanized! Also, the sample includes specimens over 3 years old, as for scientists an animal is "adult" when they are sexually mature. Now, in order to get a more reliable average figure I investigated all the reports about the Siberian Tiger Project, plus the new males/females captured by the Amur Tiger Programme and I excluded the specimens in bad shape, although it was not posible to exclude the specimens between 3-4 years old for obvious reasons. At the end, my result was of an average weight of 190 kg (n=23; range: 155 - 212 kg) for males and 121 kg (n=15; range: 110 - 136 kg) for females, taking in count only the specimens captured between 1992 and 2012. For the moment those are the most reliable figures about the body mass of the Amur tigers, but take in count that after the year 2000 more males of 200 kg or over had been captured, so I think that there is a big posibility that males over 215 kg are now there in the Russian Far East.

If we use the weights of the Amur tigers in the past, we can see that they were of about the same size of the Bengal tigers, with confirmed weights of about 250 kg and the skulls shows that they could be slightly longer too.

THE RELATION BETWEEN HEEL WIDTH AND WEIGHT IN WILD AMUR TIGERS

Decent explanation on the problems distinguishing young adults (3-4 years of age) from adults (5 year and over), Guate. Most reports on young adult males I have suggest they range between 150-180 kg. The skulls I measured show significant differences between age groups. If a table has young adults, chances are the average will be affected, especially in wild tigers. 

As to the weight of wild Amur tigers captured or photographed after 2005. In brown bears, heel width is a good indicator of weight. My guess is it isn't much different in big cats. In most male Amur tigers, the heel width ranges between 10,0-12,5 cm. If you use everything you have to get to a table that has information on age, heel width and weight, chances are you'll get a result. 

We know male tigers (including immature individuals) with a heel width of 10,0-12,5 cm. range between 100-200 kg. We also know the heel width of some individuals exceeded 12,5 cm. As far as I know, there're three reports about male Amur tigers with a heel width ranging between 13,0-14,0 cm. One of them is mentioned in 'Winter ecology of the Amur tiger' (A.G. Yudakov and I.G. Nikolaev, 2nd revised edition, Vladivostok, 2012, pp. 144). The two other reports are recent. The male below has a heel width of 13,5 cm. The photograph was first posted by Lycaon: 

*This image is copyright of its original author

It isn't easy to get to a guesstimate on his weight, because there's no table with information on the relation between heel width and weight in wild Amur tigers. In brown bears, the relation between heel width and weight is quite strong. In large individuals, a relatively modest increase in width often results in a significant increase in weight. I'll try to find the table. 

Chest girth and zygomatic width also are quite good indicators of weight. The problem, of course, is we know next to nothing about wild Amur tigers featuring in videos and photographs. This is the reason we need to find out a bit more about the relation between heel width and weight in Amur tigers. My guess is we can get a result. The information is there. 

Here's a table with information on the relation between heel width ('pad size'), weight and the effect of growth in wild Amur tigers:

*This image is copyright of its original author

Here's a bit more on the relation between chest girth and weight and zygomatic width and weight in brown bears: 

https://www.bearbiology.org/wp-content/uploads/2017/10/Glenn_Vol_4.pdf Reply

[tigerluver]

@peter, thank you for sharing that table. It gives us a dataset to create a predictive regression equation.

I split the dataset into two. The first set of graphs does not use the same individual multiple times if multiple measurements were available. Rather, each individual is represented just once with greatest pad width (and the corresponding weight at that measurement).

*This image is copyright of its original author

This next set of graphs utilized all measurements on that table such that if an individual is measured multiple times it is represented multiple times. This could be a reasonable approach as well as it still shows weight change with pad growth and is based on a greater sample size of measurements.

*This image is copyright of its original author

When pooling together males and females, the fit is mediocre however there is a significant relationship. When we split the sexes, we note that males seem to have a very strong and significant association between pad size and mass in both models (R^2 >=0.9). On the other hand, females have a poor association. What could be the reasoning for such? Perhaps the females were not in equal shape between specimens, some emaciated while others not. It is also possible the measurements weren't done as precisely. 

Using all tigers and not allowing one individual to be represented multiple times temporally, a 13.5 cm pad would weigh 226 kg. Using all tigers but allowing an individual's multiple measurements to be included in the foundation, the estimate would be 221 kg. 

Using only males and not allowing one individual to be represented multiple times temporally, a 13.5 cm pad would weigh 283 kg. Using only males but allowing an individual's multiple measurements to be included in the foundation, the estimate would be 274 kg. 

The reader can decide which formula they like best. As stated before, the pooled equation has poor r^2 and thus likely a much weaker estimate compared to the only male equations.

For the sake of completeness, I'll add in an isometry estimate. Using the largest pad sizes of the 5 males (average pad size 11.1 cm, average weight 152 kg), the isometric estimate of a 13.5 cm pad would be 275 kg. If we use all temporal measurements and allow specimens to be represented multiple times (average pad size 10.5 cm, average weight 137 kg), the isometric estimate is 291 kg. Reply

[peter]

TIGERLUVER

Many thanks for the predictive equation. I found a lot more. When I wanted to post the info, it took me some time to find this thread. I propose to continue the discussion in the tiger extinction thread. The reasons are:

a - The extinction threads are in a seperate section. It's easy to find them.
b - The discussion on the relation between 'heel width' and weight is interesting. It deserves more attention.
c - The discussion on the relation between heel width and weight doesn't belong here. 
d - It would be appreciated if you could move (copies of) all posts related to the discussion on heel width and weight to the tiger thread.  

MODS

Time and again I noticed it isn't easy to find threads. Not seldom, threads about a particular species are in different sections. A pity, as it results in dispersion of information and a lot of lost time. When I've trouble finding specific threads, chances are it isn't much different for our readers. My proposal is to start thinking about a reorganisation. Reply

[Rishi]

(04-06-2020, 02:14 AM)peter Wrote: MODS

Time and again I noticed it isn't easy to find threads. Not seldom, threads about a particular species are in different sections. A pity, as it results in dispersion of information and a lot of lost time. When I've trouble finding specific threads, chances are it isn't much different for our readers. My proposal is to start thinking about a reorganisation.

Any ideas you have in mind? PM me.
There is lot of topic overlap between threads, like say, Tiger Extinction with Predation & size/weight measurement threads. I believe my Index thread will mitigate the problem.

This one is under  Terrestrial Wild Animals › Wild Cats › Tiger  of Info section. I'm not sure how to make WildFact better aligned, other than moving the Premier League's threads to Terrestrial Animals.
That section may have made sense in 2014, but right now with Extinction threads all at their new separate Premier Section, every remaining thread from the old Premier League can be moved to more appropriate sub-forums. Terrestrial Animals is far ahead of it, arrangement wise.

If the Tiger/Lion Predation threads don't remain under Tiger & Lion sub-forums they are bound to be hard to find. Reply

[Hello]

According to Amur tiger researcher Linda Kerley,She has seen tigers of Kistora's (282 kg,112 cm) size but unfortunately never weighed so there still big ones left to match Bengal sizes.Experienced Tiger keeper Craig Kennion measured Gamin's pugmark a 14.1 cm who weighs 276 kilograms.Here is a conversation b/w Craig and Linda

*This image is copyright of its original author

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[Hello]

A pugmark of 13.75 cm

*This image is copyright of its original author

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[peter]

HELLO

1 - Regarding Eagle Raptor's remark on the captive Amur tiger with a heel width of 14,1 cm: Can you post the source?  

2 - Regarding Kerley's remark on a wild Amur tiger with a heel width of 13,75 cm: Can you post the source? Reply

[Hello]

Hi @peter ,Eagleraptor is not Craig Kennion and Eagleraptor is pretending to be Craig Kennion.Both are 2 different persons,Craig Kennion is My friend on fb and he is an experienced Tiger keeper worked for more than 30 years at Marwell,Chester,Blackpool zoo and goes on and he said someone named eagleraptor is pretending to be him .Craig shared Stud book numbers on Yahoo many years before it was posted on AVA.Eagleraptor is the one who copied his info on studbook numbers.The 14.1 cm came from my personal message with Craig,the 14.1 cm belonged to an Amur named Gamin who is 276 kilos.13.75 cm came from personal conversation b/w Craig and Linda.

*This image is copyright of its original author

*This image is copyright of its original author

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[peter]

HELLO

Thanks for the response. I knew about Kennion and the one who took his identity. I don't know if Kennion is still active. If so, tell him his knowledge of captive Amur tigers will be appreciated at Wildfact.

As to the paw prints of wild tigers. In Russia, they use 'heel width' to assess the weight of a tiger. Experience strongly suggests this method is reliable in both brown bears and tigers. 

In the tiger extinction thread, I recently posted information about the heel width of wild male Amur tigers. Tigerluver used the information to get to an equation. His equation suggests a (healthy) male tiger with a heel width of 13,5 cm., if data of wild male Amur tigers only would be used, ranges between 259-337 kg. 

You wrote Kerley saw a print with a heel or pad width of 13,75 cm., but didn't post evidence. What you posted (referring to your last post), suggests she saw a print with a heel width of 13,5 cm. (and not 13,75 cm.).

You could ask Kennion again, but maybe it's best to contact Kerley herself. She's been in the Russian Far East for a long time, has a lot of experience and (co-)wrote a lot of interesting peer-reviewed documents. Reply

[Hello]

Very welcome @peter, 13.5 cm came from this tiger and 13.75 came from another whom Linda has never seen yet and was from a personal message b/w Craig and Linda
This is the screenshot of conversation b/w them which was sent to me by Craig

*This image is copyright of its original author

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[peter]

HELLO

Thanks again. For now, we can conclude the heel width of wild male Amur tigers ranges between 10,5-13,5 cm., whereas their captive relatives can reach 14,1 cm. 

The heel width of the captive Amur tiger was measured from a print left in the mud. The heel width of the wild male Amur tigers was measured from prints left in the snow. I'm not sure, but my guess is the prints were left in frozen snow.

The captive Amur tiger with a heel width of 14,1 cm. ('Gamin') was 276 kg., whereas the heaviest wild male Amur weighed in the period 1992-2020 ('Lyuk') was 212 kg. (heel width unknown). One wild male Amur tiger captured and weighed in 2011 ('Banzai') was 286 cm. in total length measured 'over curves'. He had a heel width of 11,5 cm. and was 207 kg. Reply

[Hello]

*This image is copyright of its original author

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