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

[peter]

TIGERS IN NORTHEASTERN CHINA

a - The heaviest male Amur tiger actually weighed 

Our member 'Betty', able in Chinese, sent me a PM in which she referred to the video 'Apex' posted in this thread (see the previous post). Dr. Feng Limin confirmed he had personally seen a wild male Amur tiger of 270 kg (596 pounds). The male was weighed and Feng Limin stated the weight is accurate. According to 'Betty', Dr. Feng Limin is preparing a paper in which the tiger will be mentioned. I don't think it's superfluous to add Feng Limin, in a post on a Chinese forum not so long ago (I saw a copy), stated more than one male in northeastern China exceeded 250 kg.     

b - The young male Amur tiger that attacked a car a year ago
 
A little over a year ago, a young male Amur tiger made headlines in northeastern China. He 'attacked' a field worker and a car. Videos were posted and his weight (225 kg or 497 pounds) was discussed. Here's an article that was published 30-05-2022:

https://news.cgtn.com/news/2022-05-30/Li...index.html

According to the article, the tiger really was a young male. I doubt if he, as was suggested, even was 2-3 years of age when he was captured. In the video in the article (see above), it was stated the young tiger moved from young roe deer to adult wild boars in the period he was monitored. This 'upgrade' in prey selection isn't typical for a 3-year old male, but for a younger animal. 

The Russians, as you may remember, captured a number of youngsters a few years ago. After rehab, they were released into the wild and monitored for quite some time. Their progress was described (referring to articles published on the site of the Amur Tiger Center). The conclusion was young males and females (18-24 months of age) hunted young bears, wolves, adult deer and adult male wild boars. 

Most young males ranging between 18-36 months are 140-180 kg (310-398 pounds), but some are heavier. The young male captured in northeastern China was weighed. He really was 225 kg (497 pounds).    

c - The weight of adult wild male Amur tigers in northeastern China     

The weight of wild Amur tigers has been discussed by many for quite some time. Nearly all debates were based on a table published in 2005. That table, discussed in this thread more than once, says adult wild male Amur tigers today (referring to males weighed in the Bikin Valley in the period 1992-2004) average 176,4 kg (389 pounds). 

The problem is the table has a number of young adult males. As there are significant differences between young adult males and mature males (6-12 year of age), the question is if they should have been included. Information about captive male Amur tigers suggests they grow until they are 7-8 years of age. This is confirmed by skull measurements. As a general rule, skulls of mature males are a bit larger and heavier. My guess is it isn't different in wild male Amur tigers.  

The sample (referring to the table mentioned above) also included a male that, as a result of his bad condition, had to be 'euthanized' later.   

What I'm saying is the sample isn't representative for the population. If a table is based on a small sample, outliers have a significant effect on the average.   

Reliable information about the size of wild Amur tigers published after 2005 suggests adult males, like Miquelle said, average about 195 kg (430 pounds), maybe a bit more. Until now, the heaviest male actually weighed was a young adult of 212 kg (469 pounds), but researchers found prints of larger males. This is important, as the correlation between heel width and weight in wild male Amur tigers seems to be quite strong. Most males range between 10,0-12,5 cm. Prints with a heel width of 13,0-13,5 cm or more have been found more than once in Sichote-Alin. In northeastern China, a print with a heel width of 14,0 cm was recently found.  

The information about the weight of some large males in northeastern China provided by Feng Limin is important, as it confirms wild males, as historic records suggest, can reach, and even exceed, 250 kg (552 pounds) in good conditions. As far as is known today, adult wild male Amur tigers range between 140-270 kg (310-596 pounds). Both weights (referring to the old male 'Tikhon' and the male recently weighed in northeastern China) have been confirmed. 

d - About captive and wild male Amur tigers 

Reliable information says wild male tigers are larger and heavier than their captive relatives. This is the case in Sumatran tigers (Panthera tigris sumatrae), Indo-Chinese tigers (Panthera tigris corbetti), Indian tigers (Panthera tigris tigris) and Chinese tigers (Panthera tigris amoyensis). It's unlikely it's any different in Amur tigers. 

The average weight of captive adult males ranges between 172,7 kg (380 pounds, Hengdaohezi) and 224,2 kg (496 pounds, my sample). The average of both averages is 198,45 kg (438 pounds), but the averages in two Chinese papers recently discussed in this thread suggest the average could be 200-210 kg (442-464 pounds). Wild males, as was stated above, are a bit heavier than their captive relatives (about 5%). This means mature wild male Amur tigers (6-12 years of age) most probably average 210-222 kg (464-490 pounds) in good conditions. If young adults (4-5 years of age) and males over 12 years of age would be included, the average for all would be close to 190 kg (420 pounds), meaby a bit more.   

This is apart from conditions and individual variation. 

Using the table I posted some time ago (in this thread), one could conclude individual variation in captive male Amur tigers is pronounced. The range in weight I found (142,9-320 kg) was significant. The additional information suggests disease and age have a significant effect. Same for wild male Amur tigers. Example. 

One male, known for his preference for (adult female brown) bears, was captured three times. The first time, he was 206 kg (455 pounds) on what seemed (referring to the photograph below) to be an empty stomach. The second time, he was 170 kg (375 pounds). This, mind you, was on a full stomach. Without the roe deer he had eaten, he would have been closer to 150 kg (331 pounds). The last time he was captured, he was 202 kg (446 pounds). He entered the table discussed above (see paragraph -c-) at 192 kg (424 pounds), but the range (150-206 kg) was considerable. 

The first time he was captured, he was the heaviest they had weighed. The photograph below (including L. Kerley), however, shows a male of average size. This was confirmed by the measurements (referring to the table mentioned above). Although quite lean, his legs were long and powerful:

*This image is copyright of its original author

   

I don't know if the male below compared for length, but he seems more robust in just about every department:

*This image is copyright of its original author

Here's one of the largest males I know of. This tiger, known as 'The Beast', has a heel width of 13,5 cm:

*This image is copyright of its original author

I'm not suggesting tiger 'Dale' (also known as 'Dima') was a smallish tiger (far from it), but photographs and videos suggest some males well exceed his (maximum) weight (206 kg or 455 pounds). This impression, albeit in an indirect way (the tigers above, as far as I know, were not weighed and measured), was confirmed by Feng Limin.     

Returning to the conditions wild Amur tigers face in wild Russia. In the Russian Far East, winters can be long (up to 6 months). Although tigers frozen to death have been found ('Der Tiger', V. Mazak, 1983), healthy tigers do not seem to be affected by the cold. Their main problem, if anything, is food. If wild herbivores are decimated as a result of a crop failure or a disease, tigers will be affected. This, many think, is one of the reasons they learned to hunt bears.  

As a result of a lack of reliable information, it's impossible to say if wild Amur tigers, as many seem to think, increased in size in the last 3 decades. Maybe only few tigers were captured and measured in the period 1992-2004 and maybe more tigers are monitored today. Also remember the tigers in the table published in 2005 were captured in or close to one region only (the Bikin Valley). In that period (1992-2004), in that region, there were problems with Aldrich footsnares. According to those who know (referring to an article discussed in this thread), these had an effect on male tigers in particular. The authors, without a shadow of doubt, proved that males able to escape the footsnares did so at a cost. The damage to their teeth was substantial. It no doubt affected their health. One could even say Aldrich footsnares had an effect on the table published in 2005 and be close.        

e - Are Amur tigers in northeastern China larger (heavier) than Amur tigers in Russia?

Historical records suggest tigers shot in Manchuria (northeastern China) were larger than tigers shot in Russia, but the information I have (referring to, for instance, 'Notes on the Siberian long-haired tiger, Panthera tigris altaica (Temminck, 1844), with a remark on Temminck's Mammal Volume of the 'Fauna Japonica', V. Mazak, 1967; 'Der Tiger', V. Mazak, 1983 and 'Die Säugetiere der Sowjetunion', Band III, V.G. Heptner and A.A. Sludskij, German translation, 1980), suggests this, most probably, wasn't the case at the level of averages. 

As to today's Amur tigers. Based on what I know (referring to books, papers, documentaries, videos, articles, interviews and photographs), it seems that tigers in the northern part of Sichote-Alin in particular (Khabarowski Krai), compared to their relatives in northeastern China, aren't lacking in the size department. Information about tigers shot in Korea suggests they might have been at bit smaller than those shot in Russia and Manchuria, but the heaviest male Amur tiger accepted by biologists, at 254 kg (560 pounds), was shot near the Korean border and it wasn't the only large male shot in that period in that region. 

It is, however, likely there were, and are, regional differences in size. Based on the information provided by Feng Limin, tigers in northeastern China seem to be as large as those in the Khabarowsk region. Northeastern China (recent information) has 50-60 tigers only. This includes cubs, subadults, young adults, mature adults and old tigers. There's no information about the number of males in northeastern China, but it's clear the number is limited. In spite of that, at least 3 males, one of them a subadult, reached or exceeded 225 kg (497 pounds). Of these, one is 270 kg (596 pounds).   

That's still without tiger T26. He entered northeastern China from the north in 2015 and never left. Those who know think this male is even heavier than the 270 kg tiger (...). If you visit the thread 'Amur Tigers', you can find a bit more about this male. A new member from China recently posted about this tiger (post 905). I wonder if this is the male who left the print with a heel width of 14,0 cm. If T26, blind in one eye, is as large as they think he is, northeastern China has 4 male tigers reaching or exceeding 225 kg.      

There's no information about the size of tigers in the Khabarowsk region, but those who know think this region produces large individuals. The lack of accurate information, to be sure, isn't a result of a lack of opportunities, but of a decision: the Russians don't want to capture healthy adult males because of the risks involved. Some of these were descibed by S. Kolchin and P. Maystrenko ('The snare for tiger', 2013). I'm not sure, but it is possible the Chinese use a different method to capture a wild tiger. 

f - Videos 

f1 - The Northeast Tiger and Leopard National Park (NTLNP)

In this video (May 2020), you'll find a bit more about the new 14,600 square km Northeast Tiger and Leopard National Park (NTLNP). In this park, infrared cameras as used. Although short (4:40), the video has footage of a few Amur tigers and an Amur leopard: 
https://www.youtube.com/watch?v=rQTgfW-exXY

f2 - Russia and China

This video (Nov. 2020) offers information about the cooperation between Russia and China in the department of Amur tiger protection. Although quite long (16:42), it's interesting. It also has footage of wild Amur tigers:
https://www.youtube.com/watch?v=eEPgF9xjcIA

f3 - The Korean perspective

Here's a shortish (05:02) video about Amur tigers from the Korean perspective. The Korean perspective in a post about tigers in northeastern China? Yes, Amurtigerwise there is a connection between southeastern Russia, northeastern China and Korea. The video (Jan. 2021) also offers a bit more about the movie about a very large Amur tiger discussed some time ago ('An old hunter's tale'):  
https://www.youtube.com/watch?v=LHhf1AKnW94

In the thread 'Amur Tigers' (post 905), our new member from China posted a picture in which the old male from the movie and T26 (see -f4-) are compared. I hope our new member doesn't mind me using the result of his work: 

*This image is copyright of its original author

 

f4 - Tiger T26

The tiger in this video (Feb. 2022) could be the large male tiger T26 discussed above (see -e-). Although the video is very short (00:12), it shows the tiger is blind in one eye:
https://www.youtube.com/watch?v=OU1kZPFLJDU

The video below (April 2022) shows the same male:
https://www.youtube.com/watch?v=jrj4nNUwuao

f5 - Massive male tigers

Here's a very recent (Apr. 2022) and short (00:13) video showing a massive male: 
https://www.youtube.com/watch?v=1hJqsxmrkbg

Compared to the tiger in the video above, the male in the video below (Apr. 2022) doesn't seems as robust:
https://www.youtube.com/watch?v=c5qw9n7iy0k

Same for the tiger in this video (May 2022):
https://www.youtube.com/watch?v=axrKaU86voA

One more (May 2022):
https://www.youtube.com/watch?v=SquBJUGZy4w

And the last one (may 2022). It offers a very nice view of a healthy adult male Amur tiger. Interesting for painters:
https://www.youtube.com/watch?v=vFKKL0MrILI

f6 - The young male arrested for jumping a field worker and attacking a car

Last year (2021), a young male tiger was accused of disturbing the domestic peace in a village somewhere in northeastern China. He denied all charges, but accepted a deal after seeing the video (Apr. 2021):
https://www.youtube.com/watch?app=desktop&v=OwqygpyQnb8

After doing time in rehab (45 days), he promised to work on his attitude and accepted a collar to make sure he would:   
https://www.youtube.com/watch?v=798VCBd6LRg

Here's a bit more about the situation in May 2022: 
https://news.cgtn.com/news/2022-05-30/Li...index.html

Another video (May 2022):
https://www.youtube.com/watch?v=IwwSbJ4_sd0

His name, by the way, is Wandashan No. 1. Every now and then, a video about his life in the forests of northeastern China will be posted. Reply