Modern Weights and Measurements of Jaguars

[Stripedlion2]

(08-04-2020, 05:28 AM)peter Wrote:

(08-04-2020, 03:35 AM)Balam Wrote: From the jaguar directory thread, I posted a story on a Chaco jaguar who's pugmark width measured 10 cm, and I have felt is the same pugmark that measured close to 15 cm in length that I posted some time ago. @peter I wanted to ask you, based on the knowledge you have of the paw sizes of tigresses and small tigers, would a pugmark of a similar dimension compare? I've been under the assumption that tigresses usually have pugmarks of 10-12 cm in width. It would be interesting to draw the parallel because Chaco jaguars have been compared in the past to Sumatran tigers by hunters and comparing them to the data that we do have on tigers would give us a better idea of their size potential. Chaco jaguars are severely understudied and highly threatened.

BALAM (Onca?)

a - Difference between heel width and a pugmark
 
Before answering the question, I decided for a few words on the difference between a print (pugmark) and the heel width. In this photograph (pugmark of a male Amur tiger first posted by Rage), you can see the difference between a complete print and the heel width: 

*This image is copyright of its original author

Here's the tiger who left the print:

*This image is copyright of its original author

   
b - Heel width of wild Amur tigers

In wild Amur tigresses, the heel width ranges between 8,0-10,0 cm. In adult wild male Amur tigers, it ranges between 10,5-12,8 cm. 

The heel width in exceptional males can reach 13,5 cm. According to Tigerluver, a male width a heel width of 13,5 cm. ranges between 259-339 kg. One captive male Amur tiger in a UK zoo just over 600 pounds (272,16 kg.) had a heel width of 14,1 cm.

I don't remember if it's this tiger, but I do know he was just over 600 pounds as well:

*This image is copyright of its original author

c - Further reading

A few months ago, I posted extensively on the relation between heel width and weight in wild Amur tigers in the tiger extinction thread (posts 2,467-2,481 and post 2,492). Heel width, to keep it short, is one of the best indicators of weight in wild big cats (and brown bears). 

d - A wild male Amur tiger with a heel width of 13,5 cm.

For different reasons (discussed in the tiger extinction thread), researchers today are hesitant to dart healthy wild male Amur tigers. This means we have no option but to use data collected before, say, 2013. The heaviest weighed was a young adult male of 212 kg., but he still had some growing to do and chances are some individuals recently seen well exceed that mark. The male below had a heel width of 13,5 cm. 

Watch the short and very robust fore-limbs and the deep chest. I know the snow accounts for some loss of length, but it's clear this male is as robust as they come:     

*This image is copyright of its original author

 

Although the conditions in the southern and southeastern part seem to be a bit better, the northern part of Sichote-Alin seems to produce the largest males.  

e - A few pictures

Tracking a male Amur tiger. When this photograp was taken, not one of the captured males exceeded 205 kg. in weight:  

*This image is copyright of its original author

Based on what I have (old and new information), I'd say tigers living just south of the Himalayas could be the largest wild big cats today (averages). This photograph (taken in Rajaji) was first posted by Roflcopters. I do not doubt some males in that part of India are close to 650 pounds (294,84 kg.):

*This image is copyright of its original author

 

Here's one from Bengt Berg (northern India, close to Bhutan). The heaviest tiger he shot was 565 pounds. He didn't shoot the male that left the print below in order to allow him to pass on his genes. Berg saw the 565-pound male and the Bhutan tiger from very close range. The tiger he didn't shoot was quite a bit bigger (well over 600 pounds). 

Although known as the 'Killer of Man', the giant from Bhutan hunted male wild buffalos only. Every buffalo he killed was found with his enormous horns sticking in the ground. Berg was very impressed and wrote he must have been immensely powerful:

*This image is copyright of its original author

f - Chaco jaguars

The table you and Dark Jaguar posted in this thread says wild male jaguars in the southern part of Brazil are very robust for their length. Same for the photographs i saw. Weightwise, the heaviest no doubt compare to the largest Amur tigresses. As these range between 8,0-10,0 cm. in heel width, it's very likely the Chaco male with a heel width of 10,0 cm. was about as heavy as the heaviest tigress. 

What's heavy in wild Amur tigresses today? There's not much information, but the heaviest captured in the period 1992-2012 ranged between 125-130 kg. In that period, the heaviest males ranged between 200-212 kg. 

About 50-100 years ago, when Amur tigers were on their way out, individuals well exceeding that mark (males and females), have been shot. One of the largest females I know of, although still youngish, was 367 pounds (166,47 kg.). 

As a result of the population bottleneck of the thirties, forties and fifties of the last century, Amur tigers today are a bit smaller. Individual variation also has been affected. But the Russians are very serious about protection and the number of tigers is increasing all the time. As the conditions have improved as well, chances are wild Amur tigers will produce more large individuals in the near future. 

Back to jaguars. When measuring skulls, I noticed that skulls from jaguars shot in the southwestern part of South America were larger (and more robust) than those of jaguars shot in the northern part. I saw a large skull from Argentina and a few large skulls from Bolivia. Those who hunted them (referring to a few people I met) confirmed jaguars in the southwestern part of South America, apart from a few exceptions (like the jaguar recently poached in Surinam), are bigger than their relatives living in the northern part. 

Same for pumas, so it seems. Some males and females seen in Patagonia and the southern part of Chili seem to be in a different league. Weight- and lengthwise, large pumas in Canada and the northwestern part of the USA compare, but the Patagonians seem to have bigger, more rounded and more robust skulls.   

I hope you'll be able to find out a bit more about jaguars living in the northern part of Argentina. My guess is they more or less compare to Pantanal jaguars. Same for Bolivia. Anything known about Paraguay?

To finish the post, two pictures. This male definitely compares to a large male Sumatran tiger:

*This image is copyright of its original author

Skull of a male rainforest leopard (central part of western Africa, left) and a male jaguar from Bolivia (right). The skull of the leopard is flatter, but not much shorter (just over 1 inch). The upper canines of the leopard are missing, but my guess is they would have compared for length. The main difference between both skulls is the jaguar skull is more elevated and more robust (heavier). Photograph taken by 'Wanderfalke' in the Staatliches Museum für Naturkunde Stuttgart, 2012. 

The largest leopard skulls can exceed 280 mm. in greatest total length, whereas large jaguar skulls exceed 300,00 mm. Although generally a bit shorter, large jaguar skulls compare to skulls of male Sumatran tigers in quite many respects. One of the largest jaguar I know is (was) in the Netherlands. Unfortunately, the owner of the skull got cold feet just before we were supposed to meet:  

*This image is copyright of its original author

So it looks like Amur tigers are starting to bounce back in size. Reply